Vintage: Trio TR9000 TX/RX off frequency problem, advice please?

[M7PNB]

Looking for some guidance please.

I have a Trio TR9000 which is operating off frequency - only in SSB. FM is fine.

RX is around 12.3khz what the VFO reports
TX is also around 12.3khz off what the VFO reports

In the photo below with it tuned to 144.238.7, this is me without RIT on, listening to a caller who is actually txing on 144.300 (the UK 2m USB calling frequency). I can tune the VFO to 144.300, and use the RIT to tune in. But this doesn't rectify the TX obviously.



I have tested the above by using my SDR and comparing the frequencies. I can 'tune in' the RX via the RIT switch. Here the radio is tuned to 144.820, and the transmission shows on SDR as around 144.821.3





The radio is an eBay special, which is what it is.

I cannot for the life of me, in the service manual, work out how this is adjusted. I would have thought it would be a simple potentiometer for both SSB RX and SSB TX but maybe I'm being naive.



I repair vintage audio equipment all the time, and have a YouTube channel doing it. But this service manual has me a little stumped. Can anyone advise please?

 

[M7PNB]

Sorry just to correct, I can't seem to edit.. the photo of the radio tuned to 144.238.7 is me listening to a conversation on 144.240. I know they're tuned to .240, as they declared their intention to go there after calling on the calling frequency.

 

[merlin]

Like my Kenwood, you tune SSB, the offset is to detect either the upper or lower sideband. the 'ceneter frequency' will show the low or high edge of the signal.
Tune to 144.240, then BFO or RIT tune up to clarify. IE: in your waterfall, your tuned frequency should be set to the left edge of the signal. (USB).
When you TX USB your frequency you tune to the center. the energy in USB goes up with modulation about 2.5 KHz.
Seems to me your Trio is awful close to on frequency.
I just leave the RIT off (or center) then use the main tuning to clarify. Yea, it will show low or high depending which sideband is used.
Note, this is not like audio, this is a modulated RF signal.

 

[M7PNB]

Like my Kenwood, you tune SSB, the offset is to detect either the upper or lower sideband. the 'ceneter frequency' will show the low or high edge of the signal.
Tune to 144.240, then BFO or RIT tune up to clarify. IE: in your waterfall, your tuned frequency should be set to the left edge of the signal. (USB)

Thankyou for your reply. There are separate switches for USB and LSB.

I have just sat and worked out:

To TX on 144.300, the VFO must be set at 144.297.8

To RX 144.300, VFO must be set at 144.298.7

As you can see both are quite a way off the intended frequency.

 

[MTS2000des]

Google search for service manual, 2nd response:

http://py5sg.crafi.qsl.br:2000/manuais_e_esquemas/Kenwood/TR-9000%20Service%20Manual.pdf

Setup your bench per the SM, and perform adjustments/alignments, which start on page 35

 

[M7PNB]

Google search for service manual, 2nd response:

http://py5sg.crafi.qsl.br:2000/manuais_e_esquemas/Kenwood/TR-9000%20Service%20Manual.pdf

Setup your bench per the SM, and perform adjustments/alignments, which start on page 35

There's a lot of them. Which ones relate strictly to my issue?

That's my problem. I'm not sure, in that service manual, which items I should be adjusting.

 

[MTS2000des]

If you don't know how to do ref oscillator warp, you may want to seek a qualified technician. Basic radio servicing 101.

 

[M7PNB]

If you don't know how to do ref oscillator warp, you may want to seek a qualified technician. Basic radio servicing 101.

FM is fine, as above, this is only SSB.. so not sure why would you would suggest that.

Basic radio servicing 101 😉

 

[MTS2000des]

You have the service manual, you expect someone to spoon feed you. Really don't get threads like this. You were provided what the manufacturer provides for qualified service personnel.