I have a UHF Repeater using an ACC RC-85 repeater controller, which also 
controls a Kenwood TS-440 HF Transceiver as the Remote Base radio. All the HF 
Radio control commands seem to work fine, except the "Bump Down 500 Hz" 
command. The command is "[Remote Base Prefix]  7" -  it just has no reponse. 
But the "Bump UP 500 Hz" and the other "Bump Up/Down" - 20 Hz and 100 Hz step 
commands work just fine. It's not a problem decoding the "7" - the Touchtone 
Pad Test reads back all digits correctly. The touchtone decoder in the RC-85 
seems to work extremely well and decodes noisy signals without falsing. I can 
be mobile, using just a handheld radio that's choppy into the repeater, and 
dial around on the HF radio with hardly ever having a missed digit. 

The other minor problem I'm having is that the transmit audio for the TS-440S 
is so hot coming from the RC-85 that it's unusable. The output of the RC-85 
transmit audio is fixed level, and is controlled by the inputs from the 
receiver (in this case, the UHF repeater receiver.) If I turn down the level of 
the receive audio to the controller so that the TS-440 transmit audio is at the 
proper level, then the controller doesn't have enough audio output to drive the 
main UHF transmitter to more than about 2 kHz deviation. I'm feeding the 
transmit audio into the TS-440's "AFSK IN" rear-panel jack, as suggested in the 
RC-85 manual. Using this input, the TS-440 front-panel mic gain control has no 
effect on the transmit audio level from the AFSK IN jack.

Looking at the RC-85 manual and in an old issue of "ACC Notes" which describes 
RC-850 and RC-85 transmit audio level setting procedures, it suggests padding 
down the output of the transmit audio using an attenuator or resistive voltage 
divider. Anyone tried this and have any starting values? 

Lots of fun!

Larry K7LJ


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