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  ACC Support for the Doug Hall RBI-1 Remote Base Interface
Mysteries Explained by Chris Baldwin KF6AJM
HTML'd for repeater-builder by Mike Morris WA6ILQ
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Recently I recently got a wild idea to add remote bases to our UHF linked repeater system. Because our system uses Palomar Telecom controllers, there isnít much direct support for various remote base radios other than BCD and Motorola Syntor mobiles.

Wanting to use something a bit more current, I figured Iíd chain off one of the link cards of the Palomar Telecom and add an ACC controller. I purchased an RC-850, an RC-96 and an RC-85 on the used market and began experimenting with which controller would do the job best and with which remote base setup. I have both the FC-900 & ICOM setup, and the Doug Hall RBI-1 with TM-x31 and x41 series mobile radios. This article focuses on the RBI-1 with Kenwood radio setup.

The following is the result of what I found out about the Doug Hall RBI-1 and ACC products.

ACC RC-850 (Tested with Version 3.6 firmware)

The RC-850 was the most full-featured controller of ACCís product lineup. It fully supports the Doug Hall RBI-1 controller, with a few minor kinks.

To connect a Doug Hall interface to the RC-850, the RC-850 internal DIP switches must be set as follows:

1+2+3 = Userís Choice, 4+5+6 = OFF, 7+8 = Users Choice.

I set the RBI-1 up on Link Port 1. Other ports can be used but it is unknown if there are any feature limitations from port to port.

In the RBI-1, be sure to jumper pins 6+8 on the jumper block. This allows the ďRotor ControlĒ outputs of the RC-850 to control certain functions of the RBI-1. This is how you change power levels, turn PL decode on/off, and change the 1.2GHz radio offset.

Wire the RC-850 and RBI-1 together as per the DHE RBI-1 manual.

Entering PL tones and frequencies is done as per the RC-850 manual. Itís somewhat similar to an FC-900/ICOM interface with a few differences.

Lets assume your remote base prefix is the default, 7.

Command 79x allows you to select band units. With the Doug Hall RBI-1, only the following apply:

(The response is: 2 METER (etc.))

Using the Rotor Control commands, you can control power level and PL decode on your radios (if the radio physically supports it).

Again, assuming your remote base prefix is 7, dial the following:

What happens here is that the serial data stream from the rotor control commands is intercepted by the Doug Hall RBI-1 and the data is then reused to control RBI-1 functions. ď78Ē is just the remote base prefix + rotor control command, the three digits following it are pseudo-beam headings that output different bits to the serial port. These different ďheadingsĒ control different functions of the RBI-1, the end result of which is full control of the RBI-1 and itís associated radios with NO feature deficiencies.

RC-85 and RC-96(Tested on BOTH controllers with Version 5.2 firmware)

This is where things really get screwy. In the DHE RBI-1 manual that I have, on page 10, the following is stated:

The ACC RC-96 and RC-85 now support the RBI-1 Generic data stream. This mode will control many more functions of the Kenwood radioís than in FC-1 mode. If the Generic mode is available, ignore the ACC supplement section.

Iíve got news for you folks: The RC-96 and RC-85 donít support generic mode. Even with the latest firmware that I could locate (Version 5.2).

Another ham sent me an e-mail and stated that in HIS copy of the RBI-1 manual, itís stated that Generic mode is available in the RC-85 and RC-96 with Version 6.0 firmware. We all know that Version 6.0 was developed, people have seen it in ACC-owned controllers, but that it was never released to the populous and Link-Com chose not to do anything with it when they purchased the remains of ACC.

What this means is that the RC-85 & RC-96 communicate with the radio in FC-1 mode with a few additional options.

On the RC-96, DIP switches should be set as follows: 1-3 = User Choice, 4 ON, 5-7 OFF, 8 = Users Choice.

On the RC-85, DIP switches should be set as follows: 1-3 = User Choice, 4+5 ON, 6 OFF, 7 ON, 8 = User Choice.

In the RBI-1, pins 6+8 of the jumper block should be shorted.

What this will give you is the ability to operate TWO radios, and no more than two, via the RBI-1.

You can remotely enter frequencies and offsets. You can remotely turn PL on and off. You can remotely turn PL Decode on and off. You can remotely change the power level from low or high. But thatís it. YOU CANNOT CHANGE PL TONES REMOTELY, ONLY TURN THE PL ON AND OFF. I suggest setting the PL on the radio yourself to the most popular tone in your area, because as I said above, YOU CANT CHANGE IT REMOTELY, ONLY TURN IT ON AND OFF.

Lets assume the following for exampleís sake:

  1. Your ďUser Function LineĒ control prefix is 9, the ACC default.
  2. You have either a dual-band 2m/440 or single band 2m and 440 radios on the RBI-1.
  3. Everything is connected and you can enter frequencies and offsets without issue.

Then dialing...

Thatís the long and the short of it. I donít know how many folks out there are still playing with ACC controllers, but they are still die-hards that were once (and in some areas still are) the industry standard.

If youíre looking to add remote bases to an ACC controller, and want FULL FEATURE control of them, the following are my suggestions:

RC-850: Use the FC900 with ICOM radios OR the RBI-1. Try to use TM-x31 or x41 series radios if using the RBI-1.

RC-85 and RC-96: Stick with the FC900 with ICOM radios if you can find them. They support full PL control and everything. If you donít care about PL frequency selection, you can use the RBI-1.

Why am I bothering with this old technology? Because Iím nostalgic, and because this equipment is very much still out there and regularly becomes available for sale on Yahoo Groups and eBay. Just because itís old and no longer manufactured doesnít mean us amateurs should push it by the wayside. Think of the fun the generation before us had with this gear. Why shouldnít we keep it going?

And if anyone with connections ever manages to produce an EPROM image of RC-85 or RC-96 Version 6.0, Iíd love to see it. Even if it shows up as image files from an anonymous email address, or on a CD that is mailed to my snail mail address.

Acknowledgements and Credits:

DHE is Doug Hall Electronics,

ACC is Advanced Computer Controls, now part of Link Communications,


Chris Baldwin KF6AJM can be reached at: support [ at ] advancedcomputercontrols [ dot ] com

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This page originally posted on 26-Jul-2009

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