[TenTec] No power out on 525 Argosy

[Dave Redfearn]

Well,

I need to jog the group's knowledge base on the older Argosy transceiver.

I have a 525 Analog Argosy which was working fine up to a couple of days
ago.

 

Now, the radio does not have any output power on high or low power.

The radio appears to receive properly on all bands.

The radio keys up properly and generates sidetone in CW but no output power.

The internal fuse is good and I have verified DC power to the final board.

 

On the RF mixer board, there is a low level signal at jack 39 which varies
with the drive control and changes frequency when the band is changed.

 

At the input to the low pass filter board, junction of D3 & C32 & S1H, There
is a low level signal which stays about the same level whether the rear
panel switch is in the HI or LOW position.

 

The Ten-Tec manuals have the schematics and some basic DC voltages but no
info on signal levels through the stages.

 

What is the typical P-P signal level at jack 39 on the RF mixer board?

What is typical P-P signal level at the input to the low pass filter board
in LOW and HI power? 

 

My initial conclusion is that the driver transistors are open which I would
like a way to verify before I start disassembling the rear of the radio.

 

 

Thanks!

 

73, 
Dave Redfearn
ARS N4ELM  Lafayette, LA

QRL? de N4ELM/qrp