TRC-453 no rx/tx

[Robalo]

i am working on trc-453 with no RX/TX I replace tr544 with nte 153 already ,pa work good,pll and vco ok it look like is dead. on tx red led on.radio is like new . recheck pll alignment and evething ok.any idea ? no mods at all on this radio

 

[nomadradio]

Do you have another radio you can use to listen for any transmit signal coming from the 453?

A coax jumper plugged into the second receiver radio becomes a half-inch "sniffing" antenna if you thread the sleeve back down the cable.

If you can't hear any sideband modulation with the mike gain full up, and no carrier in AM mode, this points to a problem that's well upstream from the driver and final stages.

What to do next depends on what you can observe this way.

Is there any chance that it's been 'screwdrivered' off the air?

73

 

[Robalo]

yes i have another radio and i have no transmit signal i going start pulling driver and final to test it thank you 73's

 

[nomadradio]

Don't bother with the driver and final. You don't have a drive signal feeding into them to start with. If you did, there would be a weak signal in your monitor receiver.

Can't get output without input.

Does the sideband receive work okay? If not, the carrier oscillator may be on strike. That will kill all transmit.

73

 

[Robalo]

the carrier oscillator may be on strike. That will kill all transmit.

you got it tr24 ok,c99(10uf 10v) out off spec but c101 (47uf 10v) on short 0.7 ohms, like cobra 148 c95 thank you. radio work good now. one more for upgrades and
make you notes . C101 GO BAD ON TRC-453

 

[Handy Andy]

C101 - takes out AN612. Kills 1/2 the IF for anything AM or SSB...

Good call!