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Motorola® MTR2000 Base Station and Repeater Information and Modifications

If you are looking for information on the MTR300 Fire Tower repeater please go to the MX handheld page (since it was built by repackaging a pair of MX handhelds into the sheet metal frame from a Spectra-Tac receiver).

The main manual for the MTR2000 is the Installation and Operation Manual 6881096E20, priced in the $20 range.

The original MTR2000 sales brochure   This is a PDF of the original glossy sales brochure.   73kb PDF Some notes on the MTR2000   by Eric Lemmon WB6FLY Read this article before buying an MTR2000. It contains some excellent information including an important caution to anyone contemplating buying either a new or a second-hand MTR. Programming the transmitter idle frequency on the MTR   by Eric Lemmon WB6FLY What to do when transmitter local oscillator leakage is a problem (i.e. if you are running an MTR on a simplex channel). Setting up the MTR2000 for Battery Backup   by Eric Lemmon WB6FLY Especially when you are on a budget... A List of Module Numbers in the MTR2000   by Eric Lemmon WB6FLY In some cases the only way to determine what you have is to inventory the Field Replaceable Units (FRUs). Here is a list from the MTR manual. The DC power cable that comes with a DC-only MTR2000 station is Motorola part number 3082009X02, which comes with the station or can be purchased as a service part for about $40. It is 10 feet long, with #8 AWG stranded wires, one black and one red. The 75A PowerPole connectors are red and black, stacked vertically, with black on top and the other wire ends are stripped. There is a 30 ampere cartridge fuse in the red wire, one foot from the stripped end. If you want battery backup on your MTR2000 that has the built-in AC supply you can clone or buy the 3082009X02 cable and use the above circuit developed by Eric Lemmon. Motorola wants you to use this: The Argus Switched Mode Charger   1.43mb PDF donated by Eric Lemmon WB6FLY This is the Model L1883 Battery Reverting Charger, model "010-519-20" or "010-523-20", made by Argus Technologies in Britsh Columbia, Canada for the MTR2000 station. It is a much more complicated device than its catalog description implies, perhaps justifying its significant cost ($1451 new, dealer cost is $1222 in 2004). As noted in the manual, it must be used with an MTR2000 that includes a power supply, since its purpose is to provide only a charging and equalizing function for the backup batteries, along with various alarm and monitoring capabilities. The L1883 model is intended for the 30 and 40 watt MTR2000 stations that operate on 14 volts; the 75 and 100 watt stations must use the L1884 28 volt version. Note that to use the Argus with the MTR2000 it must be connected with the following items: 1) CDN6226A Charger Load Cable. This is intended to connect the output terminals of an Argus Battery Backup/Charger Unit to the MTR2000. This is about 10 feet of #8 red and black stranded wires and is not fused. It has the 75 ampere PowerPole connectors on one end (the DC power connector for the MTR2000 is arranged one over the other, with black on top) and the other end has ring lug terminals for the 1/4" studs on the back of the Argus. The price was $40 to $45 in 2005. 2) CDN6227 Charger Battery Cable. Goes from the Argus to the local battery. 3) TDN9879 Temperature Sensor

From an email to repeater-builder:
The MTR is a very nice unit, and the internal controller will do 90% of what most any amateur system needs to do... the unit has a connector on the back that is designed for Motos Mobile Radio Telephone Interconnect (MRTI) unit and all the interfacing can be done through that. One quirk : the microprocessor that controls the repeater internals will not pass its own power-on-self-test with the transmitter PL encoder inhibit line (pin 24 of the the 25 pin MRTI connector) grounded (i.e. active). So if your needs include switching the internal PL encoder on and off make sure that as you program up your repeater controller you set up a timer to make sure that this line is not asserted until after the self-test is finished. The simplest way is to just inhimit all repeater operation for the number of seconds that the self test takes, plus a couple extra.

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