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Antenna Systems Information (antennas, feedlines, duplexers, circulators, isolators, calculators, etc.) Compiled from a multitude of sources and donations by Mike Morris WA6ILQ (callsign) at repeater-builder dot com |
Note that the contents of this page, like most here at www.repeater-
builder.com, are totally dependent on donations of information.
If you have something to share please consider writing it up and sending it in.
If you have relevant data sheets, class handouts or any other information that we do not have here, please consider scanning them and emailing us the scans.
If you don't have access to a scanner we can arrange to get documents scanned and made into a
PDF for download.
Please email Mike WA6ILQ at (callsign) //at// repeater-builder //dot// com
for details.
| Jump to: | System Engineering Antennas Towers Connectors, Coax and Shielding Cavities, Duplexers and Diplexers |
| Combiners Isolators and Circulators Calculators Mobile Antennas Home Brew Antennas |
Just in case you are trying to locate some documentation...
Phelps-Dodge (also known as PD) was bought by Celwave (year?), which was bought by Radio Frequency Systems (aka RFS) (year?) whose web site is at http://www.rfsworld.com/RFSGlobal. If you are looking for other web pages containing information on a specific antenna - for example some repeater group whose web page mentions a Phelps-DodgePD-458 in passing - you may have to check under all three company names. For example, under Google, you would type (less the square brackets): [ "PhelpsDodge" OR Celwave OR "Radio Frequency Systems" OR "RFS" 458 ]. Note that the OR parameter in a Google search must be in ALL CAPS.MFJ bought Hy-gain. Anyone know what year?
Antenna Specialists was sold to PCTel (year?) - and their corporate web site is at http://www.antenna.com, and the product web site is at http://www.antenna.com/products.html. The 2-way mobile product model number lookup page is at http://www.antenna.com/lm_cat/index.html.
I was told recently that PCTel bought both Maxrad and Antennex (but I don't know the dates)
DB Products was bought by Andrew, but they didn't want everything. The leftovers (including duplexers) are now sold by a company called dbSpectra, located in Lewisville, Texas (the web site is at http://www.dbspectra.com). From their web site: "...in December of 2004, dbSpectra signed a licensing agreement with Andrew Corporation to manufacture and sell the Legacy Decibel Products site management equipment such as filters, duplexers, combiners, tower top amplifiers and more. These products had been outsourced and dbSpectra successfully brought them back and have since hired many of the personnel involved in the design and manufacture of these excellent products."
In March of 2006 the Laird Group of England (AKA LairdTech) purchased Antenex for about $20.5 million, and then in Febuary of 2007 bought Cushcraft for about $90 million.
And about a month later Andrew purchased the English manufacturer Precision Antennas for about $36 million.
In December of 2007 Andrew was bought by CommScope for US$2.6 Billion.
Here's the current Andrew/Commscope catalog.
In many cases you will find that manufacturers web sites have theoretical information that is applicable to all... i.e. the theory articles on Manufacturer "X" products applies to Manufacturer "Y" and to "Z". Sometimes researching other manufacturers web sites can save you a lot of money... for example, if Manufacturer "X" claims that a crystal filter will solve your desense problem. Then you go to "Y"s web site and there you discover that, yes, a crystal filter can be used in the receiver feedline to notch out a local signal, or to pass your signal. What the Manufacturer "X" web site didn't tell you, and the Manufacturer "Y " or "Z" web site did, is that in your specific case it may not work. Unless you were familiar with crystal filters you would not know that the insertion loss can be as high as 12db, which in many cases makes a crystal filter on a repeater receiver unusable.... the signal level budget just isn't there (i.e. while adding the crystal filter would kill the interfering signal, it also reduced your receiving range to 1/2 of what it was, or maybe even less). So do your homework and learn all you can about the theory behind the hardware before you hand over your money.
System Engineering
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Introductory Information for System Engineering READ THIS FIRST |
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Getting the most from your repeater system By Kevin Custer W3KKC |
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RF Communications - A Non Technical
Approach By Decibel Products Corp. Many years ago Decibel Products (a major RF hardware manufacturer) published a series of informative pamphlets on systems engineering topics. The earliest seems to be 1964. The topics included Base Station Antennas, Combiners, Selective Cavities, Duplexers, RF Transmission Lines and Lightning. All five pamphlets were recently combined into a single PDF document titled "RF Communications - A Non-Technical Approach". DB made it available on their corporate web site, and now it's available from Andrew/CommScope at their web site or as a local copy here. This document should be required reading for anyone wanting to learn aboutantenna systems. (thanks to Duane Hall KA8GVH for the pointer) |
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TX-RX Tech Aid #77001 Some very useful charts and procedures. Worth printing and adding to your tech notebook. By TX-RX Corp. |
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Help!! My repeater seems deaf By Kevin K. Custer W3KKC |
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Receiver desense testing By Karl Shoemaker AK2O of the Spokane Repeater Group (offsite link) |
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Is a 3 DB change in power really worth it? The
answer is "It Depends" By Neil Johnson WBØEMU If you are in charge of maintaining a repeater system, or building a new one, then this is worth reading. |
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Some thoughts on Repeater Receiver-to-Transmitter Isolation By Mike Morris WA6ILQ |
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Guidelines for mounting antennas on towers A scan of a guidelines page covering tower-to-antenna distances - donated by Skipp |
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ANTPLOT - A Side-Tower Mounted Antenna Pattern Prediction
Program This is a Zip file of both version 5.3 and of version 5.4 of the DOS
program originally provided by Antenna Specialists. It's noted as being "Program No. 3 of the
Antenna Specialists RF TOOLS Series". Also called "tplot" for some reason. Donated by A. Nony Mous Does anyone have Program #1, #2 and any others? |
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Recommended Coax and Connectors for the iDEN Enhanced Base Transceiver System Motorola Engineering wrote this three page discussion of cable and connector types with regard to combining, intermodulation, and other RF performace factors. They concluded that LMR-nnn and LMR-nnnn series cable is specifically NOT recommended in any radio site RF environments, especially duplex environments (where NNN is any 3-digit number and NNNN is any 4 digit number). While iDEN is (was?) a 900 MHz system the physics are the same at 28 MHz through 1296 MHz. Well worth reading. |
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HELIAX Coaxial Cable for Low Intermodulation Generation Andrew Engineering wrote this one page writeup on why foil-braid cable causes intermod. Despite the fact that you'd expect that conclusion from the makers of Heliax there's a lot less sales pitch and a lot more engineering presented than you'd think. Worth reading. |
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Where exactly is your repeater? And are you really sure? Read this before you file any paperwork and help out your local coordination folks, and prevent an FCC or FAA citation. Donated by Eric Lemmon WB6FLY |
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MIL-STD-188-124B "Grounding, Bonding, and
Shielding for Common Long Haul/Tactical Communication Systems including Ground Based
Communications-Electronics Facilities and Equipments" 3.8mb PDF file
dated 01-Feb-92 This is the newer military handbook on grounding, and is a quicker read at about 40 pages, however it says on the second page of the forward that "This Standard is further implemented by MIL-HDBK-419", listed below. This handbook is approved for public release and distribution is unlimited. |
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MIL-HDBK-419A "Grounding, Bonding, and Shielding
for Electronic Equipments and Facilities" 9.6mb PDF file dated 29-DEC-1987 This is the big military handbook on grounding. It is large, in two volumes totaling about 812 pages. Volume one is 396 pages of theory, volume two is 394 pages of practice. This download is the complete 2 volume set in one PDF file, and volume 2 starts on page 419 of the PDF file. This book covers grounding for safety, lightning, nuclear blast and most everything else. A very good read and a real eye opener. This handbook is approved for public release and distribution is unlimited. At one point (Feb 1999), the hardcopy (including postage) was FREE if you ordered it from: Commanding Officer Naval Publication and Forms Center 5801 Taylor Avenue Philladelphia PA 19120 |
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MIL-STD-464 "Department of Defense Interface Standard
Electromagnetic Environmental Effects Requirements for Systems" 1.17mb PDF
file dated 18-Mar-97 "This standard establishes electromagnetic environmental effects (E3) requirements and verification criteria for airborne, sea, space, and ground systems, including associated ordnance." This handbook is approved for public release and distribution is unlimited. Why, you might ask, is this one on a web page that covers antenna systems? Well, "electromagnetic environmental effects" includes lightning. And lightning can have seriously negative effects on antenna systems (and the radios they are connected to). |
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High power amplifiers and duplex radio Tubes vs. Transistors, By Kevin Custer W3KKC Short version: at high power levels tubes win. |
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Is this connector any good? An article on the perils of cheap connectors by Jeff DePolo WN3A |
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EMR Corp. Technical Papers Index An index of downloadable PDF papers on Isolators, Duplexer retuning, Ferrite and Hybrid Combiners, Multicouplers, Preselectors, Bandpass and Pass-Notch Cavity Resonators. |
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Using Preamps with repeaters... and why sometimes you wouldn't want to... by Mark Malm NØFAZ and Kevin K. Custer W3KKC |
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The Effects of Trees on Slant Propagation Paths By Vogel & Hagn This is an academic paper that will be of special interest to UHF, 900 & 1200 MHz system owners. |
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Best Practices Guide By Motorola Inc. This is a write up on solving interference problems at 800 MHz and oriented towards Public Safety communications, but it's worth reading by any repeater owner or builder. |
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InterferenceTechnical Appendix By Motorola Inc. This is intended to be an add-on to the "Best Practices Guide" above. Also very worth reading. |
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Calculating Your Radio Horizon By A. Nony Mous |
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Radio Mobile Coverage
prediction software by Roger Coudé VE2DBE A bit of a learning curve,
but darn good stuff (offsite link) A Yahoo group supporting it is at http://groups.yahoo.com/group/Radio_Mobile_Deluxe If anybody wants to put together a "Getting Started" article, we'll make room for it here. |
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The calcualtors, especially Dale Bickels HAAT, Coordinate and Distance calculators are useful. Scroll down to the Calculators section for them. |
Combiners
| Introductory Information about Combiners READ THIS FIRST | |
| About Combiners By DB
Products, copyrighted 1975. From the preface: "This booklet has been written for the many people engaged in two-way radio communications who are NOT radio engineers. A non-technical presentation of a rather complex subject has been attempted in an effort to bring about a better understanding of combiners used in two-way radio systems." |
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| Tuning Instructions for the DB-4350 and DB-4360 Low Loss Combiners 8kb? A one-page PDF file. | |
| Tuning
Procedure for Two-Transmitter Combiners DB-4351, DB-4381, DB-4352, DB-4382, DB-4384 |
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Description & Installation and Tuning Instructions for the ACT27nnJ2 and DBNXTL27nn Transmitter
Combiner 85 KB A two-page PDF file. 5-Channel Models: ACT2705J2, DBNXTL2705 10-Channel Models: ACT2710J2, DBNXTL2710 15-Channel Model: ACT2715J2 20-Channel Model: ACT2720J2 |
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| TuningInstructions for the DB-4379 Low Loss Combiner 9 KB A one-page PDF file describing a unit for up to 8 transmitters. | |
| Celwave 220 brochure 580 KB PDF Back when 220-222 was stolen from the hams to be a new land mobile radio band Cellwave put together a brochure with the tech specs on all of their 220 products plus three sample system diagrams. The products include the PD220-8, PD220DT, 92.0101, and 93.0024 antennas, the TJD220-5T transmitter combiner, PD1604B cavity, PD5042-2 duplexer, PD5279 cavity, PD5280-1, PD5280-2 and PD5280-3 duplexers, PD1602 low-pass filter, PD506-2A duplexer, PD5091-2A dual notch cavity, PD5090-2B/3 bandpass filter and the PD5090-2A bandpass cavity. |
Isolators and Circulators
| Introductory Information for Isolators and Circulators READ THIS FIRST | |
| What's a circulator? a.k.a. Properties of a Ferromagnetic Circulator By Kevin Custer W3KKC | |
| The Care and Feeding of the RF Isolator a 14 KB PDF by William F. Lieske, Sr. Founder, EMR Corporation | |
| An Elementary Introduction to Ferrite Isolators, Circulators and RF Loads a 1mb PDF file A TX-RX Corp. "Seminar Series" writeup - 14 pages. | |
| Circulators and Ring Hybrids a 363 KB PDF by Wolfgang Borschel DK2DO | |
| FieldTuning Instructions for Dual Junction Tunable Isolators a one-page 21 KB PDF file by Decibel Products | |
| Generic single stage / single-section isolator tuning instructions from EMR a 26 KB PDF file donated by Eric Lemmon WB6FLY | |
| Generic dual stage / dual-section isolator tuning instructions from EMR a 55 KB PDF file donated by Eric Lemmon WB6FLY | |
| Sinclair's instructions on tuning isolators Donated by Eric Lemmon WB6FLY | |
| Microwave Associates
7R011 Isolator Tuning Instructions Donated by Micheal Salem N5MS Good for 125 watts, with 0.9 db insertion loss typical with 1.3 db max. The isolation can be as high as 60 db with 50 db typical. |
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| Data sheet
on the DB 4318H-2C High Band Single Channel filter and isolator A two-page PDF file describing a Decibel Products 164-168.5 MHz dual isolator but the directions apply to similar units. The drawing is in error, it does not show the termination (a Bird Termaline) on the output port. |
Cavities, Diplexers, Duplexers, Theory, and More
| Introductory Information on Cavities, Diplexers, and Duplexers READ THIS FIRST | |
| DUPLEXERS - An Introductory
Tutorial by Jack Daniel KD6YVL (offsite link) This is a nice writeup that should be titled "Duplexers 101". Well worth reading. |
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| Theory and Testing of
Duplexers by Jacques Audet VE2AZX This is a large (60 pages) technical writeup that should be titled "Duplexers 102". Again, well worth reading. |
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| Technical Duplexer Page with good theory and explanations, and some homebrew construction notes. By John Portune W6NBC | |
| Understanding,
Maintaining & Re-Tuning Antenna Duplexers 145 KB PDF By William F. Lieske, Sr., Founder
of EMR Corporation A good basic theory writeup, including the differences between Band Pass and Band Reject. The original copy at the EMR web site |
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| Combating
Spurious Output And Overloading With Cavity Filters 1.2mb PDF by TX-RX Corp. A "Seminar Series" writeup that covers the theory behind cavity filters - mandatory reading for those unfamiliar with them. |
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| Coaxial Resonators, Applied theory and practice, with photos by Mike Pinfold ZL1BTB (offsite link) | |
| Duplexer Theory and Tuning 351 KB PDF by Dave Metz WAØAUQ An overview of duplexers from an amateurs point of view, with some good hands-on info and some photos of a good home-brew duplexer. |
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| Interference Control Through The Use Of Cavity Filters And Ferrite Isolators 900 KB PDF by TX-RX Corp. | |
| Technical Notes on Duplexer Problems and Remedies 1mb PDF By TX-RX Corp. | |
| The Design of High Isolation Duplexers
And A New Antenna For Duplex Systems 755 KB PDF An IEEE Transactions publication from March 1965 by W. B. Bryson of Communications Products Company, a division of Phelps Dodge. |
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| A Guide to Duplexer Specifications over 130 different models, by Paul Kelley N1BUG (Contributions to the list are very welcome) | |
| Tuning
and Adjusting Vari-Notch-Duplexers 185 KB PDF by TX-RX Corp. A "Seminar Series" writeup that covers the theory behind cavity filters and isolators. |
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| T-Pass
Expandable Cavity Muticoupler System 500 KB PDF by TX-RX Corp. A "Seminar Series" writeup that covers the various type of cavity-based multicouplers and the T-Pass design. |
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| The Hybrid Ring Duplexer A comprehensive explanation of the Hybrid Ring, by Kevin Custer W3KKC | |
| Six Meter Heliax Duplexer Design by Jim Poll WB5WPA (off-site link that is no longer available) Here's one implementation of the above design by Oscar Quintanilla KF6YB (off-site link) Here's another implementation of the above design by Mike Perryman K5JMP (off-site link) Six Meter Heliax Receive Filter Construction and Testing article based on the above designs, by Robert Meister WA1MIK and David Malicki N1OFJ. Note that this is NOT a full duplexer; just the receive half (but it could easily be extended to a full duplexer). Yet another implementation of a six meter filter by Tim Ahrens W5FN |
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| Some Tests on Duplexer
Loops 234 KB PDF by Jacques Audet VE2AZX Some interesting observations, including scope traces. |
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| Using
open stubs to notch interference By Nico PAØNHC (offsite link) An excellent article on reducing paging transmitter (and others) interference into 2m repeaters. Note that common European usage is that a comma is used where Westerners usea period to mark decimals, for example 144.550 MHz is written as 144,550 MHz so readers used to the period will have to do some mental "translation". In this article Nico has used a mix of both forms so it can be a little confusing on the first read. |
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| GE Datafile Bulletin 10002-1, A 25-250 MC
Quarter Wave Stub Filter General Electric produced several useful RF engineering DataFile Bulletins
(the ones we have are available for free download from the GE LBI page
at this web site). This one is a 400 KB PDF file, and is subtitled: "Even though General Electric Two Way Radio Transmitters well exceed FCC requirements for spurious radiation, the 60-80-db sprious attenuation provided may, in a few situations, be insufficicient to provent interference. This bulletin describes the construction of a filter, useful for supressing spurious radiation at one specific frequency...." |
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| Someone say 6 meter duplexer? A comprehensive conversion of a lowband pass cavity to BpBr by Jeff DePolo WN3A... | |
| How do I tune this notch duplexer? by Kevin Custer W3KKC | |
| A Homemade Duplexer for 2-Meter Repeaters by
John Bilodeau, W1GAN (from the July 1972 QST magazine) Note: In the 35-plus years since this article was written, the spring-contact based BNC has fallen out of favor. Type N connectors (and to a lesser extent the TNC connector) are much preferred over BNC connectors as they depend on a silver-to-silver screw compression contact, plus they can handle more power. You must use double shielded coax in the harness. RG-55 is mentioned in the article, but I'd use RG-400 and compensate on the inter-cavity lengths. If anybody has built this unit with better connectors and modern cable, and would like to update this article please do so, then write an article we can put here. |
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| Tests of the DCI VHF and UHF 4-polebandpass
filters by Robert W. Meister WA1MIK These filters definitely do the job, meeting or exceeding manufacturer's specs. They cover the entire 144-148 and 440-450 MHz bands and have sharp cutoffs. If you need more filtering, they also sell 6, 8, and 10-pole filters with attenuations over 80dB. These handle 200 watts and can be used at repeater sites. |
| RFS / Celwave See also Phelps-Dodge, as Cellwave bought that company and continued many of their products under the Cellwave name. Click here for Celwave antennas | ||
| Celwave model 696, 696SR (UHF), 896 or 896SR (800-960 MHz) Duplexer 86 KB PDF file Donated by Allan Crites WA9ZZU, scanned by Eric Lemmon WB6FLY | ||
| Celwave Duplexer Cable Harness Lengths (oriented for printing) 44 KB PDF file Donated by A. Nony Mous | ||
| Celwave 220 brochure 580 KB PDF Back when 220-222 was stolen from the hams to be a new land mobile radio band Cellwave put together a brochure with the tech specs on all of their 220 products plus three sample system diagrams. The products include the PD220-8, PD220DT, 92.0101, and 93.0024 antennas, the TJD220-5T transmitter combiner, PD1604B cavity, PD5042-2 duplexer, PD5279 cavity, PD5280-1, PD5280-2 and PD5280-3 duplexers, PD1602 low-pass filter, PD506-2A duplexer, PD5091-2A dual notch cavity, PD5090-2B/3 bandpass filter and the PD5090-2A bandpass cavity. |
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| Decibel Products Click here for DB antennas Note that Decibel Products ("DB") and Phelps Dodge ("PD") used similar model numbers at times. A DB-506 is very different from a PD506... |
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| Data Sheet on DB's line ofpower dividers - Three page PDF
264 KB donated by John Lock KFØM This writeup covers the K522 & K542 for 144-174 MHz, the K526 & K546 for 406-512 MHz, the K528 & K548 for 800-960 MHz and the K528M & K548M for 1850-1990 MHz |
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| DB's pipe and tower mounting clamp kit DB-365-OS Early version donated by John Lock KFØM | ||
| DB's pipe and tower mounting clamp kit DB-365-OS & ASPR616 (later version) | ||
| Installation
and Tuning Instructions for DB Band Pass Cavity Filters 50 KB This information is pretty generic despite the models listed: DB-4001 (148-174 MHz), DB-4002 (118-512 MHz), DB-4011 (70-88 MHz), DB-4013 (88-118 MHz), DB-4015 (118-148 MHz), DB-4020 (406-420 MHz), DB-4018 (225-400 MHz), DB-4021 (406-512 MHz), DB-4026 (406-512 MHz), DB-4028 (806-960 MHz), DB-4042 (30-50 MHz), DB-4170 (138-174 MHz), DB-4171 (450-512 MHz). |
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| Tuning Instructions for the DB-4022 (UHF) & 4029 (800 MHz) band pass / band reject cavities 31 KB A two-page PDF file | ||
| DB-4023 UHF duplexer (3 cavity) and 4081 (4 cavity) spec sheet donated by W. M. Kahl N6KYD | ||
| Tuning Instructions for the DB-4030 (four cavity) and
4032 (six cavity) Low Band Duplexers five page 920 KB PDF donated by W. M. Kahl N6KYD Same drawing sized to be printed on 11x17 paper Both donated by Chris Nicholson N9LLO |
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| Installation and
Alignment Instructions for the DB-4036 (mid-band), 4044 and 4046 (high-band) Base Station
Duplexers 47kb A two-page PDF file describing wide-spaced (3 MHz and 5 MHz) duplexers that are not of much use to hams, but would be to public safety and disaster services folks. |
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| DB-4042 Resonant Filter Modifications An offsite link to KB6MIP's Technical Information Page articles. | ||
| DB-4048 duplexer specs (high band - 146-174 MHz) - an eight
page PDF file |
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| Modifying/Improving the DB-4048 Notch Cavity Duplexer By Ralph Hogan W4XE | ||
| Installation
and Tuning Instructions for the DB-4055 & 4056 (high band), 4067 & 4068 (406-420 UHF) and 4071 & 4072
(450-470 UHF) duplexers 40 KB A two-page PDF file Here's a photo of the internals of a 4072 housing. |
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| Installation and Tuning on Decibel Products 4057 (three cavity) and 4058 (four cavity) high band duplexers Two page 120 KB PDF donated by A. Nony Mous | ||
| Catalog sheet on the DB-4060 & 4062 Band Pass/Band Reject duplexers 55 KB PDF I have a DB-4062, which is the 6 cavity version of the 4060. It was old when I placed it in service in 1997 but worked OK. Over the years it just slowly deteriorated until it became essentially unusable. Finally I took the thing apart to investigate, and was able to restore it to excellent function after 15-20 hours of work. I created a web page that covered my experience... |
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| Tuning and Installation Information on the DB-4075 and DB-4076 UHF Bandpass Reject duplexers 91kb | ||
| Tuning Information on the DB-4090 806-960 MHz Bandpass Reject duplexers 43kb | ||
| Installationand Tuning Instructions for the DB-4104 (low band), 4040 (high band) and4075 (UHF) single-cavity notch filters 25 KB A two-page PDF file | ||
| Installation and Tuning Instructions for the 4307, 4308 and 4309 Hybrid Couplers 14 KB PDF file. | ||
| Installation and Tuning Instructions for the DB-4318H-2C Single Channel Filter and Isolator 10kb A two-page PDF file describing a 164-168.5 MHz unit but the directions apply to similar units. | ||
| Motorola Note that over the years Motorola house-labeled many products made by Antenna Specialists, DB, PD, and others. If anyone has a translation list or chart (even just a few model numbers) we'd love to offer it here. |
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| Info on the T1480 series high band 4-can duplexer / cavity filter panel 1.14Mb PDF file of the official Moto manual that covers the two-cavity and four-cavity models (T1481, T1482, T1485A, T1485AF, T1487A, T1487AF) | ||
| Info on the T1500 series UHF 4-can duplexer / cavity filter panel There's quite a bit of info, so it has it's own web page that covers the T1500, T1501, T1502, T1503, T1504, T1505, T1506 and T1507 units. | ||
| If anyone has any experience or tech info related to the Motorola TU313 series of low band cavities we'd appreciate it. | ||
Phelps-Dodge
Note that Phelps Dodge ("PD") and Decibel Products ("DB") used similar model numbers at times. A PD506 is
very different from a DB-506...
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PD-506 manual 263 KB PDF Donated by Allan Crites WA9ZZU, scanned by Eric Lemmon WB6FLY NOTE: You CANNOT tell from the model number if a PD-506 is for 144-174 or for 220-225 MHz ! You have to look at the frequency label ! This is a 4-cavity pass-notch duplexer than is supplied as either a 144-174 or 220-225 MHz version. At high band it will work from 600 KHz to 7 MHz separation, and at 220 it will work at from 1 to 5 MHz separation. Rejection is specified at 80 db, and under 2 db insertion loss. |
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Phelps-Dodge 522-509 manual 1.1 MB PDF Donated by Bill Hudson W6CBS The manual says Celwave as they bought Phelps-Dodge, and this particular manual was printed after the purchase. Does anyone have the factory spec sheet or catalog sheet, the tuning instructions or can supply a couple of photos? |
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PD-526 manual 1.45 MB PDF courtesy of Joe Szczech K1IKE who says "It's a UHF book, ignore the 146MHz frequencies on the front cover, P-D shipped the wrong manual with some 2 meter duplexers". Photo 1 Photo 2 Eric Lemmon WB6FLY wrote: This is a 6 Cavity UHF Repeater and Base Station Duplexer that is an outstanding performer. Specs: Frequency Coverage = 435 to 470 MHz. Minimum Frequency Spacing = 3 MHz. Minimum TX to RX Isolation = 100 dB Maximum Insertion Loss = 1.0 dB TX Bandwidth = 0.025 MHz. RX Bandwidth = 0.025 MHz. Maximum Power Input = 250 watts Connectors = "N" Female Maximum VSWR (50 ohms) = 1.3:1 This duplexer is also sold by Motorola as part number 0185417U05, which has a current (mid 2009) dealer price of $ 1,173.00. It is made for Motorola by RFS/Celwave, which sells the same unit as PD526-4-2. It is the X182AD Option for Quantar, Quantro, and MTR2000 stations. I have an identical unit in service on a 100 watt UHF MTR2000 repeater, and it is an excellent performer. Prior to installation, I verified that its isolation was better than the 120 dB specified- a very good figure. |
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PD-638-509-6 manual 263 KB PDF Donated by Allan Crites WA9ZZU, scanned by Eric Lemmon WB6FLY This is a 6-cavity pass-notch mobile duplexer that is available as a 150-162, 162-174, 220-225, or 471-512 MHz unit. - 150-162 or 162-174 MHz: 150 watts, 75db rejection, 1.2 dB insertion loss at 2 MHz spacing. At 5 MHz the insertion loss drops to 0.7 dB. - 220-225 MHz: 100 watts, 75db rejection, 2 dB insertion loss at 1.6 MHz spacing. - 470-512 MHz: 75 watts, 75db rejection, 1.7 dB insertion loss at 3 MHz spacing. |
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PD5042-1 VHF Duplexer data from Motorola 960 KB PDF scanned by Eric Lemmon WB6FLY Motorola relabels the Celwave model PD5042-1-50 duplexers and includes them as factory option with VHF Quantar or MTR2000 stations. Their part numbers are 0185417U01 for the 132-146 MHz range, 0185417U02 covers 144-160 MHz, and 0185417U03 covers 158-174 MHz. |
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PD-7540, PD-7560, PD-7640, PD-7660 duplexer manual 109 KB This unit is also called the "MiniPlexer". This is a UHF flat-pack mobile notch-only duplexer that is limited to 40 watts and comes in two ranges: 406-435 and 435-470 MHz and in 4 can or 6-can versions (7n40=4-can, 7n60=6-can). The 4-can version provides 50 dB rejection and 1 dB insertion loss at 5 MHz spacing, and the 6-can version provides 75 dB and 1.3 dB. Like any notch-only duplexer, any frequency outside the notches rides right through... Donated by A. Nony Mous. PD-7540, PD-7560, PD-7640, PD-7660 duplexer manual 518 Kb This is a later verion of the same manual, with enough new information to be worth having both versions available. Donated by Allan Crites WA9ZZU, scanned by Eric Lemmon WB6FLY. |
Sinclair Labs
Sinclair's literature is inconsistent on the model number layout. Some has a dash/hyphen
(like in "Q-202G"), while some doesn't. If you are searching for something try the search both
ways.
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P-Series Duplexer Specifications Sheet Covering the P-1C01-G, P-1C02G, P-201G, P202G, P203G, P-301G, P-302G, P-303G models by Sinclair Corporation. | |
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Sinclair Q202-G cable harness drawing
88 KB courtesy of Eric Lemmon WB6FLY Eric wrote in an email: A while back I set up a Q-202G duplexer for a local radio club. The duplexer was originally made for and used on a commercial pair in the 152-157 MHz band, and no matter how much work was spent on tinung the duplexer it would not perform. I had the club purchase a new low-split harness from Sinclair. When it arrived, I took careful measurements of both the new and the old harness, and the results are here... If the harness on your duplexer is the high-split version, with about 12 inches between tee centers, you will never be able to achieve optimum peformance on 2m, especially in the 145 repeater range. Some people "stretch" the cables by adding 90 degree elbow adapters to the ends as a test, but while that works you will eventually end up buying or making a new harness. The factory-made harness uses Delta brand crimped connectors, and is priced in the area of $250. Eric continued with "If I were to do this again, I would consider fabricating the harness myself, with genuine Delta brand connectors and tees, which can be purchased for a total of around $120". If you do, don't forget to use real mil-spec RG-214 or RG-393 coax with the silver plating (look up "duplex noise" and "LMR-400" elsewhere at this web site). |
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Tuning instructions for "P" and "Q" series cavity duplexers, and FP, FR, FQ series cavities manual CM-1008 by Sinclair Corporation. | |
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Tuning instructions for the Q-202G, Q-208G, Q-218G, 2B02G, Q-2B02G, Q-2B17G series cavity duplexers manual FP-1032 by Sinclair Corporation. | |
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Catalog sheet and Specifications for the 6 cavity Res-Lock Q-Circuit VHF Duplexer | |
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Tuning instructions for the Q-Series, ResLok
4 - Q‑circuit Duplexers - manual number CM-351. Written on the front is "Sincl Q2330E" |
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Installation and Tuning instructions for the Q‑Circuit Res-Lock
Duplexers - manual number CM-1009. This manual covers the Q-1220E (66‑88 MHz), Q-2220E (132‑174 MHz), Q-2222E (148‑174 MHz), Q-3220E (406‑512 MHz) and Q-4220E (806‑960 MHz) duplexers. Photos of a new coupling loop for a 2220E: Photo 1 Photo 2 Photo 3 Photo 4 |
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Duplexer Tuning Instructions for the R101G to R116G and R-1C01-G,
R-1C02G, R-1A01G models (manual number CM-159): Note: This manual also covers a large number of other models in the 2H-30, 2H-37, 2H-43, 2H-66, 2H-77, H-30, H-37, H-43, H-66 and H-77 series. The actual list is on the first page. |
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Modification of R101, R104, or R110 for amateur 6 meter operation (manual number CI-051). | |
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Hybrid Ring Duplexer Tuning Instructions (manual CM-106) (theory on the W2EUP-designed Sinclair Hybrid Ring Duplexer). | |
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MR-354, MR-356 and MR-3332 406-512 MHz mobile duplexer catalog sheet 191 KB JPG file - scan of a catalog page. | |
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Mobile duplexer MR-354 Specification Sheet 2-page 88 KB PDF file donated by Ted Maczulat VE7TFM | |
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Mobile duplexer MR-356 Specification Sheet 2-page 87 KB PDF file | |
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MR series mobile duplexer tuning
(manual number CM-1010) 150 KB PDF Covers the MR-254 and MR-256 (high band, 4.5-10Mhz separation), MR-354 and MR-356 (UHF, 5-10Mhz separation), MR-454 and MR-456 (806-952 MHz, up to 45 MHz separation) units. Note that these duplexers are rated at 50 watts or less. The high band units are built for either 148-160 MHz or 160-174 MHz splits, the UHF are built for either the 406-450 MHz or 440-512 MHz splits, and the 800/900 units are built for 806-890 MHz and 928-952 MHz splits. |
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SRL-101C Low band antenna information The sheet says "30-50 MHz" but gives info on 30-90 MHz. 440 KB PDF file. | |
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SRL-229 High band antenna information | |
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"FP", "FR", "FQ" Series Bandpass Filters Product Description Page 1 34.2 KB Page 2 28.9 KB Donated by Eric Lemmon WB6FLY. | |
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"FP" Series Electrical Specs 27 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FR" Series Electrical Specs 31 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FQ" Series Electrical Specs 30 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FP", "FR", "FQ" Series Tuning 48 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FP" Series Tuning 61 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FR"Series Tuning 68 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FQ"Series Tuning 71 KB PDF file donated by Eric Lemmon WB6FLY | |
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"FP","FR", "FQ" Series Parts 23 KB PDF file donated by EricLemmon WB6FLY | |
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"P","Q", "R" Series Description 37 KB PDF file donated byEric Lemmon WB6FLY | |
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"P" Series Electrical Specs 40 KB PDF file donated by Eric Lemmon WB6FLY | |
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"Q" Series Electrical Specs 41 KB PDF file donated by Eric Lemmon WB6FLY | |
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"P" and "Q" Series Preliminary Tuning 32 KB PDF file donated by Eric Lemmon WB6FLY | |
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"P" and "Q" Series Outlines 42 KB PDF file donated by Eric Lemmon WB6FLY | |
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"P" Series Retuning 58 KB PDF file donated by Eric Lemmon WB6FLY | |
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"Q" Series Tuning 86 KB PDF file donated by Eric Lemmon WB6FLY | |
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"P" and "Q" Series Parts 33 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Description 53 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Systems 79 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Electrical Specs 59 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Mechanical Specs 64 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Curves 49 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Typical Systems 67 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Tuning 49 KB PDF file donated by Eric Lemmon WB6FLY | |
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"C" Series Parts 71 KB PDF file donated by Eric Lemmon WB6FLY | |
| Telewave | |
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| TPRD-series Duplexer TuningInstructions 50 KB PDF file donated by A. Nony Mous Generic tuning instructions for their pass/reject duplexers. |
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| TPRD-1554 & 1556 Duplexers 92 KB PDF file donated by A. Nony Mous These are VHF pass-reject duplexers good for 350 watts. The TPRD-1554 is VHF 4 cavity and the 1556 is 6 cavity. |
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| TPRD-4544 & 4744 Duplexers 104 KB PDF file donated by A. Nony Mous UHF 4 cavity pass-reject, 250watts. The 4544 model is for 400-470 MHz, the 4744 is for 470-512 MHz. |
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| TPRD-9044 Duplexer 88 KB PDF file donated by A. Nony Mous 890-960 MHz 4 cavity pass-reject, 250 watts If 4 cavities are enough in your RF environment then this is an ideal unit for 900 MHz amateur repeaters. |
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| Overview ofTX-RX Low Band Duplexers 2 mb PDF Also hassome Tech Aid documents | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Overview of TX-RXHigh Band & 220 MHz Duplexers 2 mb PDF Includes a chart explaining their model numbering system Hint: The center digit pair are the magic numbers: 13=30-40 MHz, 14=38-50 MHz, 29=88-108 MHz, 36=132-150 MHz, 37=144-174 MHz, 38=132-174 MHz, 41=148-174 MHz, 52=215-250 MHz, 65=406-430 MHz, 66=442-450 MHz, and 97=1215-1300 MHz. |
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| Data Sheet on the TX-RXmodel 28-37-02A 144-175 MHz duplexer 2.7 mb PDF If a 4-cavity model is enough for your situation, this is the ideal model for a 2m repeater - it will handle 400 watts at 500 KHz spacing with 85 db of isolation. Otherwise look at the 28-37-11, it's the 6-cavity version with 100 db. Personally, I'd rather have the extra headroom of the 6-cavity version. And TX-RX will sell you an upgrade kit of the extra cavities and cables. |
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Instruction Manual
on the Vari-Notch Duplexers (4" Cavities) 673 KB PDF While this appears to be a generic manual on the TX-RX duplexers with four inch cavities it contains a chart saying it is specific to the following units:
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Instruction Manual
on the Vari-Notch Duplexers (6" Cavities) 189 KB PDF While this appears to be a generic manual on the TX-RX duplexers with six inch cavities it contains a chart saying it is specific to the following units:
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| WACOM and Remec | |
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| WACOM started out as Waco Communications in Waco, Texas. At some point WACOM was bought by Remec, and in November of 2001 was sold to TX-RX. | |
| Notes on the Wacom WP-641 BpBr Cavity by Kevin Custer W3KKC | |
| Field Tuning Instructions for Remec WP-604, WP-609, WP-612, WP-621, WP-629, WP-639 and WP-641 VHF Duplexers donated by Eric Lemmon WB6FLY There's one repeated error in this writeup... In Figure 1 and Figure 2 you need to terminate the unused port with a good dummy load. |
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| Field Tuning Instructions for Wacom WP-604, WP-609, WP-612, WP-621, WP-629, WP-639, WP-641 and WP-652 units donated by Ivan OZ1HYG This is an earlier version of the above file (it's from Wacom), and the instructions are a little different. |
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| Field Tuning Instructions for Wacom WP-678-R2 and WP-665-R2 UHF Duplexers donated by Eric Lemmon WB6FLY | |
| Spec Sheet for WP-604 (low band, 4-cavity) 371 KB PDF | |
| Spec Sheet for WP-621 and WP-641 (high band, 4-cavity) 218 KB PDF | |
| Spec Sheet for WP-623 and WP-643 (high band, 6-cavity) 178 KB PDF | |
| Spec Sheet for WP-629 and WP-639 (high band, 4-cavity) 188 KB PDF | |
| Spec Sheet for WP-652 and WP-653 (220mc, 4-cavity) 248 KB PDF This is the March 1997 version of the sheet. The September 1985 version (no image yet) has a few differences: the older sheet says 220-300 MHz, 1.0 MHz min. spacing, 350 watts max, gray enamel finish. The newer sheet says 210-260 MHz, 1.0 MHz min. spacing, 200 watts max, black enamel finish. The frequency response charts look identical, as do the loss & isolation specs. |
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| Spec Sheet for WP-665 and WP-678 (UHF, 4-cavity) 215 KB PDF | |
| WP-687-3943 Catalog Sheet (900 MHz, 4-cavity) 145 KB GIF | |
| WP-687-3943 Spec Sheet (900 MHz, 4-cavity) 1.65mb PDF | |
| WP-687-3943 Test Sheet (900 MHz, 4-cavity) 1.35mb PDF | |
| WP-687-3943 Field Tuning Instructions (900 MHz, 4-cavity) 409 KB PDF | |
| WP-4941-7941 Spec Sheet (900 MHz, 2-cavity) 2Mb PDF | |
Antennas
| Introductory Information on Antennas READ THIS FIRST | |
| Radio Antenna Engineering By Edmund A. Laport This is a 1952 textbook and the original copyright has expired. The PDF file is 38.5 Mb. At the time, Mr. Laport was the Chief Engineer of RCA International Division. While the book is oriented towards antennas up to 30 MHz, the Preface is worth reading (4 pages) as theory doesn't depend that much on wavelength. The Introduction (11 pages) has some math, but it's also very interesting. | |
| The W1GHZ Online Microwave Antenna Book By Paul Wade W1GHZ (ex N1BWT) An excellent text, and worth reading. (offsite link) | |
| Antenna Design for
Omnidirectional Repeater Coverage By James Ruxlow N9SN What do you do when you need omni coverage, and you have to side mount the antenna to a triangular tower that is over fifteen feet on each face? The Western Illinois ARC figured it out. And their solution works well. |
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| Precipitation Static and Duplex Radio... The Phenomena and the Cure! Rain and snow clouds contain more than rain and snow By Kevin Custer W3KKC. | |
| Help!! I have a crackling noise in my repeater Why it's there and how to cure it... By Kevin Custer W3KKC. | |
| Vertical and Horizontal antenna separation charts Provided by Kevin Custer W3KKC. | |
| Information on a Cycloid Dipole (also known as circular polarization) antennas By the WA7X crew (offsite link) | |
| "Calculating Downtilt" by Scala Division of Kathrein Corp (Technical Bulletin #112) 39 KB PDF | |
| Side
Mounted Radiation Patterns by Scala Division of Kathrein Corp 123 KB PDF Appears to be a scan of a page from from a catalog. |
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| Side mount antenna patterns 273 KB PDF A scan of a page from the "Engineering Notes" section in an old DB Products catalog |
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| Omni-Directional Gain Vertical Collinear Construction
Project By Mike Collis WA6SVT Yes, you too can build a Stationmaster - for any frequency from 2 meters to 1.3 GHz This writeup originally appeared in the May 1982 issue of 73 magazine, later revised in the August 1990 issue of 73 magazine. |
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Build A 9 dB, 70cm, Collinear
Antenna From Coax By Michael Martell N1HFX (offsite link) Yes, you can build a decent home base station antenna from RG-58 coax. |
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Fiberglass Antenna Painting Procedure by Celwave Corp., provided by Mike Dees N3EZD See the next article as well. |
| Retuning a Stationmaster type antenna By Jim Barbour WD8CHL | |
| Cheap Yagi Antennas for
VHF/UHF By Kent Britain, WA5VJB for the Clear Lake Amateur Radio Club of Houston, Texas. This article describes a easy-to-build inexpensive yagi (beam) antenna that can be built for 2m, 220, 440, 900 or 1296 MHz. |
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| A QST article on a homebrew
discone 375 KB PDF file from the May 2003 issue The article describes it as 144 through 450 MHz but it would work just fine at Civil Air Patrol (CAP) frequencies (just plug 139 MHz into the sizing formula) and at GMRS frequencies. Personally, I'd use copper screening, not steel hardware cloth. And discones aren't limited to 2m and up, as this photo of a commercial 25-75 MHz discone will show (photo by WA6ILQ). While it looks like the support mast is on a rooftop air conditioner, it is actually mounted into a tripod base about 20 feet on the far side of the unit. A search of the QST archives shows an article on constructing a 40 through 10 meter discone in the July 1975 issue and a followup/correction in September. |
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| A Copper Cactus Dual-Band J-Pole Antenna Project By Tony Petersen N7QVC | |
| A homebrew Digital TV Antenna
Project By Make Magazine If you are going to make one I suggest you first seal the wood with two or three coats of sealer. |
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| If anyone has any other good homebrew antenna projects let WA6ILQ know. | |
| There is a section on mobile antennas towards the bottom of this web page. |
| Advanced Electronic Applications / AEA | ||
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For information on AEA antennas including the Isopole please see the AEA page. | |
| Andrew | ||
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| 2008 Andrew Corp. Base Station Antenna Systems Product Selection Guide 2.99 MB PDF | ||
| Antenna Specialist | ||
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| Antenna Specialist 3 and 5 element yagi antenna instructions 400 KB PDF | ||
| Celwave | ||
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| A detailed drawing by Skipp of the Celwave-built Motorola TDE6090A welded yagi beam antenna 69 KB PDF file This is a two page PDF, the first page is Skipp's measurements, the second is the Celwave drawing. There is enough information here that anyone with a welder could make their own very strong winter-ice-proof welded 10db gain yagi antenna. Note that the element length measurements shown in the diagram are for 420 MHz frequencies. If you need a physically strong very good UHF point-to-point link antenna then use this design as your model. | ||
| A PDF of a fax describing the Cellwave low band dipoles 166 KB PDF The products include the PD320 (one element, 2.5db, 10 feet of tower space), PD322 (two elements, 5.0db, 24 feet) and PD324 (four elements, 7.5db, 55 feet) side-mount antennas. | ||
| Celwave 220 brochure 580 KB PDF Back when 220-222 was stolen from the hams to be a new land mobile radio band Cellwave put together a brochure with the tech specs on all of their 220 products plus three sample system diagrams. The products include the PD220-8, PD220DT, 92.0101, and 93.0024 antennas, the TJD220-5T transmitter combiner, PD1604B cavity, PD5042-2 duplexer, PD5279 cavity, PD5280-1, PD5280-2 and PD5280-3 duplexers, PD1602 low-pass filter, PD506-2A duplexer, PD5091-2A dual notch cavity, PD5090-2B/3 bandpass filter and the PD5090-2A bandpass cavity. | ||
| Decibel Products / RFS | |
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| IMPORTANT !! A letter suffix indicates the range that an antenna is built for: 138-150 MHz, 150-160 MHz, 155-165 MHz, or 164-174 MHz but that the actual end frequencies and the assigned letter is NOT consistent across the product line. For example, on one product (i.e. one model number) an "A" model might be 150-159 MHz, while on another product an "A" model might be 150-155 MHz (4 MHz narrower). While in many cases an "A" range is the one that starts at 150 MHz, it can vary with EACH antenna model number: one antenna might have "A" be the 138-150 MHz range, and another might have "E" be the 138-150 MHz range. Be very careful that you check your range letter definition before you spend your money (on new or used antennas) ! | |
| Data sheet on the DB-201 ground plane omni antenna: This is the so-called "bent-over" ground plane that is rated at unit gain and 500 watts. This is a one-page version from the Allen Telecom vintage 717 KB PDF file It was available for any frequency from 30 MHz to 512 MHz. The ranges are: A=30-33 MHz, B=33-37 MHz, C=37-42 MHz, D=42-50 MHz, E=66-88 MHz, F=100-144 MHz, G=144-150 MHz, H=150-174 MHz, J=225-406 MHz, JJ=220-222 MHz, K=406-512 MHz, L=Uncut 30-50 MHz, M=Uncut 144-174 MHz, N=Uncut 406-512 MHz. This is a two-page version from DB Products dated 1995. |
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| Cutting chart for the DB-201 Page 1 159 KB Page 2 111 KB Allen Telecom version courtesy of Russ Stafford W3CH The same info in a 4 page PDF, better presented, from DB Products . |
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| A poor scan of the data sheet on the DB-212 side mount omni antenna (33-88 MHz) Page 1 260 KB Page 2 203 KB Drawing of the diagram on Page 2 34kb Here's the Andrew version of the same catalog sheet (and a much better scan), courtesy of Allen Wilde N1IOE and here's the DB-212 tower mounting instructions, also courtesy of Allen Wilde N1IOE |
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| You can move a low band DB-212 to 6m by basically freeing up the trombone section of the antenna, adjusting the postion, then locking it down again. Just measure the current length of the dipole and then multiply this length by (current-freq divided by the new-freq). So if the current length is 184 inches and the current freq is 46 MHz and your destination frequency is 52.5 MHz the new length (in inches) is therefore 184*(46/52.5).... To change the length you will need to remove the pop-rivet and a little dimple that the production line uses to hold the trombone in place until the rivet is installed. Sometimes the VSWR depends on the tower face. If you want to super tune the antenna set the antenna up on a tower leg several feet offthe ground, preferrably a little over a 1/2 wave if you can do it. Then adjust the trombone to the length you calculated and apply a little RF power and check the reflected power. Then get a long stick and start moving the trombone slowly while watching the reflected power. When you get the best possible VSWR, stop and redo the rivets. Personally I'd add a bead of non-acidic silicone bathub sealer to water-seal the joint. | |
| Detailed measured diagram of the low-band four-element DB-212 wiring harness Courtesy Bill Cotter N4LG. | |
| WA1ZYX's web page about modifying the DB-212 elements for 6 meters Off-site Link. | |
| Detailed harness lengths for various DB-222 multi-bayantennas Courtesy of Paul Dumdie W9DWP. | |
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DB-224 catalog data (PDF files): Decibel DB-224 Data Sheet 156 KB Andrew DB-224 Data Sheet 140 KB DB-224 Instruction Sheet 153kb Here's the instruction sheet that comes in the box with the DB-224 Page1 964 KB Page2 1,032 KB Page3 819 KB Courtesy John Lock KFØM. The DB-224 is the standard antenna that all other 2m/ high band repeater antennas are measured against. The nearest substitute for the DB-224 is the RFS Celewave 340. Both cost a little more than a fiberglass antenna but will easily last 20-30 years, and don't have the cracked joint duplex noise problem, nor will you have a pile of fiberglass toothpicks on the ground after a nearby lightning strike. How many Hustler, Comet or Diamond antennas will you go through in 20-30 years? The DB-224 is rated at 80 MPH winds, but that's wishful thinking unless you side mount it with clamps on BOTH the top AND the bottom. Frankly, chosing to mount your antenna on the tower top only to get a few extra feet isn't worth a bent or broken metal support tube, and if your antenna is side mounted (even if the tip is only 6 feet down from the tower top) the tower itself (or someone else's antenna) can be the lightning rod and take the hit. Note that all "DB-224"s are not the same... they may all be tower-mounted exposed dipole arrays with 6 to 8db of gain (depending on the pattern), it's the suffix letter that is of utmost importance:
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| A detailed drawing of the DB-224-A and DB-224-E 104 KB PDF file A 2-page PDF donated by Skipp. Note that the element length measurements are shown for both the "A" (150-160 MHz) range and the "E" (138-150 MHz) range. There is enough information here that anyone with some experience bending aluminum tubing can build one for themselves. Or if you are going to build your own and want extra strength you could use aluminum rod. | |
| Another detailed drawing of the DB-224-E 60 KB PDF file Donated by Doug Zastrow WBØUPJ. Note that the element length measurements shown in the diagram are for 136-150 MHz frequencies. | |
| More DB-224 wiring harness drawings 60 KB PDF file Donated by A. Nony Mous. Complete with calculations. | |
Details of the DB-224-E wiring harness 1.6 MB PDF file Donated by A. Nony Mous. Additional detailed drawings of
various parts of the wiring harness can be found below (all are PDF files):
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| Conversion calculations for moving your DB-224 to a different band split. 90 KB PDF file All of the magic calculations plus coax types necessary to redo your DB-224's wiring harness and set the element length and spacing. | |
| The DB-225 is a single element, 5db gain dipole station antenna that provides a "semi-circular radiation pattern" (their term, not mine). It uses a director element that is built into the dipole assembly to shape the pattern - if you end up with a used one and it is missing the director there's no telling what the final pattern will look like... The antenna can be ordered for any frequency from 30 MHz to 174 MHz. The catalog claims that you can stack the antennas and get 8 db gain with 2 antennas and 11 db gain with 4 antennas. The data sheet is very specific that it must be mounted "2 to 3 feet below the top of the tower or pipe support. At the same time it must be clear of all guy wires or metah objects for 2 to 3 feet." From an email from Ken Decker WA6OSB: Here's the paperwork that was shipped with a DB-225. I thought it might be useful in the R-B Antenna section. DB-225 data 303 KB PDF (3 pages) |
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| DB-228 catalog data (PDF files): DB-228 Data Sheet 87 KB DB-228 Instruction Sheet 60kb Note that on this antenna an A suffix indicates 150-160 MHz, B=155-165 MHz, C=164-174 MHz and E=138-150 MHz. The DB-228 is essentially two DB-224s on one 41-foot long mast, and can be ordered with a phasing harness that makes it one antenna - and that makes it the ultimate 2m repeater antenna (10 to 12db depending on the pattern). The catalog sheet shows the "normal" mounting has being a split mount: the top half is above and the bottom half is below the top of a tower (i.e. the bottom half is side mounted with two clamps at the middle and bottom); however, unless you want to be the lightning rod the DB-228 can be fully side mounted with the two brackets at top and bottom, or an optional third bracket can be added in the middle (I certainly would, especially in any area that has a problem with high winds, antenna icing, or both). Or if you need extra RX-TX separation: order it with the -S (split kit) option and use it with two feedlines and a split duplexer as separate DB-224 receiving and transmitting antennas. |
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| DB's installation instruction sheet on the DB-264 155 KB PDF Courtesy of Paul Kelly N1BUG The DB-264 is a 4 element dipole array that is constructed for any 10 MHz segment of 150-285 MHz. This is the model that has the feed harness hidden inside the support pipe. I've seen one of these on 224 MHz, and it's rugged! |
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| Anyone have any data sheets or instruction sheets on the DB-304 ?? | |
| DB's instruction sheet on the DB-314 114 KB PDF Courtesy A. Nony Mous The DB-314 is essentially a 8 UHF dipoles (a DB-408,6.6db gain) and 4 high band dipoles (half of a DB-304, 3.2db) on the samemast, with separate feedlines. If you need a commercial gradedual band antenna, this is it. Or if you are limited to oneantenna, then order this guy and use it as separate 2m and 440 antennaswith two feedlines, or with a pair of commercial-grade TX-RX Corp. (or similar)"diplexers" that put both antennas on one feedline. But don't try and use one on a 147.09 MHz; repeater paired with a second repeater whose input is 441.275 MHz, or 147.36 MHz; and paired with 442.075 MHz; (do the math... and it doesn't matter what antenna you have in that situation). |
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| Skipp's measurments drawing of the DB-402-B 26 KB PDF An early 4 dipoles antenna. Measurements are for 450-470 MHz. | |
| The DB-404 UHF dipole array is two pairs of UHF dipoles mounted to a mast. Photo Here is the factory data: (PDF files) DB 404 Data Sheet 93 KB DB 404 Instruction Sheet 131 KB Catalog sheet Page 1 879 KB Catalog sheet Page 2 568kb | |
| The DB-408 is essentially two DB-404s stacked on one longer mast (almost 9.5 feet long) and can be ordered with one or with two feedlines (the "split kit"). Specify Omni or Offset pattern when ordering, and if top or side mounting when ordering. For side mounting order the DB-5012 mounting kit. Here is the DB-408 UHF dipole array factory data: DB-408 Data Sheet 93 KB DB-408 Instruction Sheet 80 KB (PDF files) On this antenna the power limit is 250w, the frequency range A = 406-420, B = 450-470, C = 470-488, D = 488-512. The "E" range is either 482-494 or 440-450 depending on which catalog you read, be very, very careful when ordering one. Do it by frequency range, not suffix letter. |
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| DB-411 UHF dipole array factory data: (PDF files) DB 411 Data Sheet 75 KB DB 411 Instruction Sheet 217kb |
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| The DB-420 is essentially two DB-408s stacked on one longer mast and can be ordered with one or with two feedlines (the "split kit"). Specify Omni or Offset pattern, and if top or side mounting when ordering. | |
This is the 450-470 MHz version. Anybody have a drawing (or the measurements) for 440-450 MHz ? |
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The DB-420 UHF dipole array Assembly and Mounting Instructions 145kb PDF file |
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| Factory 1-page data sheet on the DB-492, DB-493 and DB-498 806-960 MHz Yagi beam antennas 130 KB PDF This is the data sheet on the welded beams that are 6, 8 or 9DB. The 492 and 493 are light duty, the 498 is heavy duty. Phasing harnesses for 2 or 4 antennas are available for up to 15DB of gain. |
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| Factory data sheet on the DB-5004/DB-5030 Outrigger 378 KB PDF This is the data sheet on the fiberglass outrigger that supports the Stationmaster and SuperStationmaster style fiberglass monopoles. You want to use at least one, in really high wind/bad weather areas I've seen two on a 21 foot SuperStationmaster). |
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| Motorola Note that over the years Motorola house-labeled many products made by Antenna Specialists, DB, PD, and others. If anyone has a translation list or chart (even just a few model numbers) we'd love to offer it here. |
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| The 1964 manual for the TAD1000-series coaxial VHF antennas donated by Skipp Description, Installation, Assembly, Parts. 150 KB PDF file Covers the models TAD1001x, TAD1002x, TAD1003x, TAD1004x, TAD6071x, TAD6072x, TAD6073x, TAD6074x (where "x" is an "A" or a "B"). | ||
| VHF unity-gain antenna model informationand specifications for the TAD1010-series antennas donated by Skipp 255 KB PDF file More info on the TAD1001, TAD1002, TAD1003 and TAD1004 models listed above, plus info on the TAD1012x, TAD1013x, TAD1014x, TAD1021x, TAD1022x, TAD1023x and TAD1024x series (where "x" is an "A" or a "B"). | ||
| VHF 3dB-gain antenna model informationand specifications for the TDD602x-series antennas donated by Skipp 240 KB PDF file Covers the models TAD6021A, TAD6022A, TAD6023A and TAD6024A units. | ||
| VHF 5.5dB-gain antenna model informationand specifications for the Motorola branded Stationmaster style antennas donated by Skipp 268 KB PDF file This sheet covers the models TDD6071A, TDD6072A, TDD6073A, TDD6074A, TDD6075A, TDD6081A, TDD6082A, TDD6083A, TDD6084A, TDD6085A, TDD6090A, and TDD6100A. | ||
| Telewave | ||
|---|---|---|
| Does anyone have scans of the literature that Telewave ships with their dipoles? | ||
Towers
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|
How to look up a tower location Lists all FCC registered towers - broadcast, cellular, everything... (offsite link - to the Berkana server) |
|
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Tower lookup page at the FCC web site (offsite link - to the FCC server) |
| The Rohn Towers 2004 Catalog 38 Mb PDF file This was sent in anonymously and it's a big download. | |
| We'd like to get a scan of the Andrew and the DB catalog as well. | |
Feedline, Connectors, Coax and more...
| Introductory Information for Feedline, Connectors, and Coax READ THIS FIRST | |
| A document on the properties of different types of UHF
(PL259) connectors. 4.3 MB PDF file by Allan B. Crites WA9ZZU As a result of my extensive review of documents in my possession and in response to the document referenced above I am the author and others only extracted parts to be used in an Engineering Report which included my measurements and log book gathered data, and drawings, to which my engineering supervisor appointed by the company assembled the data and other pages, and added his name first above mine, even tho I had done the work. You Kevin Custer, do hereby have my permission to publish this document in its entirety on your website Repeater Builder. Allan Crites WA9ZZU | |
| WA2ISE's chart of the specs of common coax cables By Robert Casey WA2ISE | |
| Another chart of thespecs of common coax cables (offsite link) Courtesy of Coastel Cable Tools of Syracuse, New York | |
| More specifications (bend radius, velocity factor, loss) of common coaxial cable types By A Nony Mous | |
| Yet another chart of cable specifications of common coaxial cable types By TX-RX Corporation | |
| Amphenol Coax Cable Catalog version W1 16 MB PDF
file courtesy of John Lovallo W9GC I have no idea what year this was published, but it has to be pre-1963 as it's pre-ZIP codes. | |
| Double Shielded Coax Cable The differences between
RG-142 and RG-400, and why you DON'T want to use RG-142... by Eric Lemmon WB6FLY With a few additional notes on RG-214 and RG-223... | |
| Shielding Effectiveness.... A 268 KB PDF Document by Andrew Corp. covering the types and parameters of shielded cables. This is a local copy, the original copy is here. | |
| Installing PL-259 connectors on FSJ1-50A 1/4" Superflex Heliax a photo article by Tony King W4ZT. | |
| MIL-SPEC-C17 for RG-9/U dated
25-July-1946 40 KB PDF courtesy of Eric Lemmon WB6FLY RG-9 is an older double shielded cable that had a center conductor of 7 strands of 21 ga silver plated wire, an inner braid of 34 ga silver plated braid and an outer shield of 34 ga unplated copper braid. | |
| MIL-SPEC-C17 for RG-9A/U dated
25-July-1946 40 KB PDF courtesy of Eric Lemmon WB6FLY RG-9A/U was the same as RG-9/U except that on the A series cable both braids were silver plated. | |
| MIL-SPEC-C17
for RG-21A/U and RG-222/U dated 7-sep-1955 82 KB PDF courtesy of Eric Lemmon WB6FLY RG-21 is considered obsolete and has been replaced by RG-222 in all new designs. This is a high loss cable, over 30 dB per 100 feet at 400 MHz. | |
| MIL-SPEC-C17 for RG-58A/U dated
18-July-1985 268 KB PDF courtesy of Eric Lemmon WB6FLY This is the mil spec for real RG-58. Most of what is sold as RG-58 these days isn't anywhere close to mil-spec stuff - all you have to do is check the braid, then count the strands on the inner conductor. The mil-spec calls for a tinned copper braid and 19 strands on the inner conductor. The mil-spec stuff has a loss of 4 dB per 100 feet at 50 MHz, and 17 dB per 100 feet at 400 Mhz (and if you do the math that's 3.4 dB in 20 feet! What's teh cheap stuff going to be?). Note that this is a PVC based cable that can no longer be used in aerospace applications due to the fact that when PVC is burnt (i.e. with flames) it gives off toxic gas. | |
| JAN-C17 for RG-83/U dated
25-JUL-1946 68 KB PDF courtesy of Eric Lemmon WB6FLY This is the Joint-Army-Navy spec for the 35 ohm coaxial cable whose major use today is in the phasing harnesses for multi-antenna (or multi-element in a single antenna) arrays. | |
| MIL-DTL-17/60D (with
Ammendment 1) for cable type RG-142 dated 12-Oct-2006 135 KB PDF courtesy of Eric Lemmon WB6FLY This is the mil-spec for real M17/60-RG142 - the stuff with a solid inner conductor of silver plated copper covered steel wire, a solid, extruded PTFE dielectric core, dual 36 ga silver-coated copper braids, and less than 30pf of capacitance per foot. Note that this stuff is intended for use as RF jumpers in general purpose, high temperature, vibration and movement-free applications, NOT as feedline. It has a loss of 3 dB per 100 feet at 50 MHz, and 9.3 dB per 100 feet at 400 Mhz. | |
| MIL-SPEC-C17/74C for "Cables,
Radio Frequency, Flexible, COaxial, 50 Ohms, Unarmored M17/74-RG213 and Armored M17/74-RG215 dated
18-July-1985 311 KB PDF courtesy of Eric Lemmon WB6FLY This is the mil-spec for real RG-213 - the stuff with 17 strands of copper wire, a solid, polyethelene dielectric core, a copper braided shield with better than 95% coverage. Note that this cable is intended for use as feedline in general purpose low temperature applications. It has a loss of 1.2 dB per 100 feet at 50 MHz, and 4.8 dB per 100 feet at 400 Mhz. Note that this is a PVC based cable that can no longer be used in aerospace applications due to the fact that when PVC is burnt (i.e. with flames) it gives off toxic gas. | |
| MIL-SPEC for RG214 dated
24-Sep-1986 335 KB PDF courtesy of Eric Lemmon WB6FLY RG-214 is the good double-shielded coax that has the stranded silver plated center conductor (each strand is individually silver plated). Both shields are made from 34ga silver plated copper wire. The inner shield exceeds 95% coverage and the outer shield equals or exceeds 98% coverage. It has a loss of 1.7 dB per 100 feet at 50 MHz, and 6.8 dB per 100 feet at 400 Mhz.Note that this is a PVC based cable that can no longer be used in aerospace applications due to the fact that when PVC is burnt (i.e. with flames) it gives off toxic gas. | |
| MIL-SPEC for RG214 dated
1991 215 KB PDF courtesy of Eric Lemmon WB6FLY This is the new RG-214 that meets the requirement of the vertical flame test. It has the aluminum coated polyester tape layer between the outer braid and the outer jacket. | |
| This is
Amendment 1 to MIL-SPEC C-17/75F for RG214 and RG365 dated 1998 4.4 KB PDF courtesy of Eric
Lemmon WB6FLY This is simply an administrative update. | |
| RG-222/U - see RG-21 above | |
| MIL-SPEC C-17/84B for RG223 dated
1977 388 KB PDF courtesy of Eric Lemmon WB6FLY RG223 has been pretty much replaced in all amateur and LMR applications by RG400. RG223 is an RG58-sized coaxial cable that has a silver plated solid center conductor and double shielded silver plated braid. It has a loss of 4.8 dB per 100 feet at 50 MHz, and 12 dB per 100 feet at 400 Mhz. If you read the spec sheet carefully you will see that RG223 is rated for just 86 watts at 400 MHz. For higher power in this size cable you will want to use RG400. RG223 also has 50% greater attenuation at 50 MHz and 15% greater attenuation at 400 MHz than RG400. Note that this is a PVC based cable that can no longer be used in aerospace applications due to the fact that when PVC is burnt (i.e. with flames) it gives off toxic gas. | |
| MIL-SPEC C17/127C-RG393 for cable type
RG393 dated 11-May-1981 293 KB PDF courtesy of Eric Lemmon WB6FLY RG-393 is the replacement for RG214. It has similar construction with the stranded silver plated center conductor (each strand is individually silver plated). It has a solid extruded PFTE dielectric core. Both shields are made from 34ga silver plated copper wire. The inner shield exceeds 95% coverage and the outer shield equals or exceeds 98% coverage. It has a loss of 1.7 dB per 100 feet at 50 MHz, and 5 dB per 100 feet at 400 Mhz. Page 4 of this PDF has a return loss spec and graph. | |
| MIL-DTL-17/128B (with
amendment 2) for cable type RG400 dated 25-Feb-2005 94 KB PDF courtesy of Eric Lemmon WB6FLY RG-400 is the RG58 size coax that has construction similar to RG-214. It has the stranded silver plated center conductor (each strand is individually silver plated). It has a solid extruded PFTE dielectric core. Both shields are made from 34ga silver plated copper wire. Both the inner and outer shields exceed 93% coverage. It has a loss of 3.2 dB per 100 feet at 50 MHz, and 10.55 dB per 100 feet at 400 Mhz. It can handle 1100 watts at 400 MHz. Page 4 of this PDF has a return loss spec and graph. Note that if you put 100 watts into a three-foot long jumper you will get about 93-94 watts out the other end, with a 6-7 watt loss in just THREE feet. It is jumper material, not feedline! | |
| We'd like to have similar info on the various corrugated copper (i.e. "Heliax") cables. |
Calculators (dBm / voltage, intermod, fade margin, etc.)
|
Converting between dbm and millivolts or microvolts A no-math
graphical calculator. It's only a xerox copy of the metal rim of a attenuator wheel from a Measurements Corp.
Model 80 RF Signal Generator... but it's very handy. Courtesy of Ray Von Neumann K6PUW I suggest that you print this out and tape it to the front panel of your signal generator that is calibrated in µV and mV only. Once you realize how dbM numbers work you will find yourself referring to it on a regular basis. | |
| Converting between dbm andmillivolts or microvolts A no-math tabular calculator (a lookup table). The above xerox of the attenuator scale is easier to use. | |
| dBm to Microvolts Conversion Chart By IFR Corp. The above xerox of the attenuator scale is easier to use. | |
| Anonline intermod calculator from AudioTechnica Note that this is oriented to wireless microphones, but since it handles up to 30 frequencies it is very handy. (offsitelink). | |
| Another downloadable intermod calculator This one is shareware written by KE6QH. | |
| This downloadablecalculator program figures intercept points and device intermod levels This one is is from Kessler Systems Inc. (offsite link) | |
| This online calculator program from TCS Consultants, Inc. saves the site description to a 'cookie' file on your computer. (offsitelink) | |
| Onlinefade margin calculator program from TCS Consultants, Inc. This is neat! (offsite link) | |
| FCC HAAT (Height Above Average Terrain) Calculator (offsite link to the FCC web site) | |
| FCC Coordinate Calculation Program (offsite
link to the FCC web site) This is a useful calcualtor for point-to-point links... "This program will calculate the end coordinates, in degrees, minutes and seconds, given an initial set of coordinates, a bearing or azimuth (referenced to True North or 0 degrees), and a distance...." |
|
| FCCCoordinate Conversion
Program (offsite link to the FCC web site) "This utility permits the user to convert latitude and longitude between decimal degrees and degrees, minutes, and seconds. For convenience, a link is included to the National Geodetic Survey's NADCON program, which allows conversions between the NAD83 / WGS84 coordinate system and the older NAD27 coordinate system. NAD27 coordinates are presently used for broadcast authorizations and applications." |
|
| FCCDistance Calculation Program (offsitelink
to the FCC web site) "This program will calculate the distance and azimuth (referenced to True North) between two sets of coordinates on the earth." The last four calculators above are courtesy of Dale Bickel of the USA Federal Communications Commission. The FCC also has a number of "Conversions" calculators including FM Channel to Frequency, FM Frequency to Channel, TV Channel to Frequency Band, Feet to/from Meters, Miles to/from Kilometers, dBu to/from mV/m, kW to/from dBk, Relative Field, Transmission Line Efficiency, and more. | |
| An old DB Products DOS program that calculates down-tilt for antennas 128 KB ZIP file | |
| An old DB Products DOS program that plots some antennapatterns 383 KB ZIP file | |
| An old DB Products DOS program that gives you some insightinto the effects
of side-mounting vertical antennas 134 KB ZIP file The above three programs were supplied by Dave Gartner WD6AXM. |
Mobile Antennas
| Introductory Information on Antennas READ THIS FIRST | |
| A Motorized Mag Mount for Mobile
Antennas 1.53 MB PDF file from the May 2005 issue An interesting modification to an off-the-shelf Diamond mount. |
|
| Base and mobile antenna cutting chart from Larsen Antennas a 668 KB PDF file from the Larsen web site, specifically the Technical Reference page. (offsite link) | |
| Mobile antenna patterns and designations a 1.6mb PDF file from the Larsen web site. | |
| Low band radios that cover a wide frequency range (like the GE Delta, GE Rangr, Motorola Syntor X or Syntor
X-9000 which covers 28-54 MHz in one range) have a big problem: the antenna bandwidth is much narrower than the
radio is - most low band antennas are limited to about 1 MHz in bandwidth. Motorized autotuning antennas
have been around since before World War II, but a really good design is fairly recent (the so-called "screwdriver"
design, invented and patented by Don Johnson W6AAQ in 1991 - almost all other units on the market are a direct
pirated copy or a enhanced redesign of the original). Back in mid-1985 Motorola came up with a no-moving-parts
solution: a "Diplex Antenna Matching" kit that allowed two differently cut low band whip antennas on one radio (i.e.
one antenna could be on 36 MHz and the other on 43 MHz), and set up in a way that prevented them from
interfering with each other. The two antennas can be cut to any two low band
frequencies. Here is the complete documentation on the kit (Motorola
manual part number 68-80100W86, a 1.9mb PDF), which contains three pages of info - enough to duplicate it yourself. If you need more than two fixed 1-mhz-wide "windows" then you need a good screwdriver antenna and a self-contained autotuner like an SGC. The phrase "self-contained" is important here, some autotuners from Icom, Kenwood and Yaesu are dependent on the radio they are connected to for frequency info and connot be made to work with common Motorola, GE, etc. land mobile radios. PS - if anyone wants to supply the coax measurents for 10m and 6m, or supply a replacement cutting chart that goes down to 28 Mhz (or even 27 Mhz) and up to 54 Mhz we will publish it. |
|
| The KØBG web site (link to another web site) Alan Applegate KØBG lives in Roswell, New Mexico and has created a very good reference web site for mobile amateur radio operators. I was pointed to it by a police department radio tech. While the site has a lot of material oriented to HF mobile, there is a lot of information that is relevant to VHF operation as well. Just look at the index along the left edge. If you look at nothing else, the Alternators and Batteries page and the Antenna Mounts page is worth your time. And if you have (or are going to buy) a screwdriver antenna then his comments are REALLY worth your time. |
|
| W8JI's page on Inductors and Loading Coil Current
(Mobile and Loaded Antennas) (link to another web site) Charles Rouch has a good web page on loading coils and how they work. It's HF oriented but the math is the same. |
|
| Urgent Communications Mobile Radio
Installation Notes (link to another web site) Urgent Communications is a two-way radio industry publication, and their web site has some notes on mobile radio installations. |
|
| You've heard of co-phased antennas? Well, here's the co-tanger antenna. |
Home Brew Antennas, Etc.
|
A mobile coaxial sleeve antenna for
2m 450 KB PDF file from the Aug 2001 issue of QST The sleeve vertial (actually a coaxial dipole) is handy when you have no ground plane to work with, like on a bicycle, a motorcycle saddle bag or a Corvette rear deck. |
|
| 440 MHz Folded Dipole Repeater Antenna 222 KB PDF file This is a two page PDF file of the classic 73 Magazine construction article by Chuck Kelsey WB2EDV - yes, you can build yourself a DB-224 folded dipole array. | |
| A Portable Quad for 2 Meters 1.56 MB
PDF by R. J. Decesari WA9GDZ from the September 1980 QST. While this was designed as a backpacking antenna it makes a decent t-hunting/fox hunting antenna that you can store in a hard case made from a piece of plastic sewer pipe with a glued plug on one end and a threaded cap on the other end. |
|
| Homebrew Coaxial Dipole for VHF or UHF
1 MB PDF file from the July 2009 QST by John E. Portune, W6NBC Another variation on the coaxial dipole originally intended for base station use for 146, 220 or 440 MHz. Performance is equal to a J-pole, but it?s smaller, less obtrusive and easily weatherproofed. Personally, I think this design could be easily adapted to be used as a mobile no-ground-plane-required antenna. |
|
| Garbage In, No Garbage
Out 2.5 MB PDF file by John E. Portune, W6NBC from the July 1996 issue of 73 Magazine. Another John Portune article on a homemade cavity. |
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This web page created and first posted 14-Oct-2004.
Layout and hand coded HTML © Copyright 1995 and date of last update by Mike Morris WA6ILQ
This web page, this web site, the information presented in and on its pages and in these modifications and conversions is © Copyrighted 1995 and (date of last update) by Kevin Custer W3KKC and multiple originating authors. All Rights Reserved, including that of paper and web publication elsewhere.