Well this time I think I have found the problem! After measuring the
voltage at a reasonably accessible area of the transmitter switching circuit
it looked to me like the 80 meter switch was always on. The readings on the
various coils were correct when the rig was on 80 metres but screwy on the
other bands. (If anyone wants the details please feel free to contact me
directly.)
I discussed my analysis with Paul Clinton (WD4EBR, Service Manager) and
others at Ten-Tec and they agreed that the 80 metre circuitry was likely the
problem. A shorted switching diode or a shorted transistor the culprit.
They hope to get a "Care Package" with the appropriate parts into the mail
early next week. I will now begin the dismantling process.
But before I put this item to rest I have some comments to add:
1) Thanks to all on the reflector for your assistance and insight.
2) Thanks to Ten-Tec for the prompt response to my problem.
3) A 2nd thanks to Ten-Tec for a great manual (explaining all the
circuitry in plain language) and complete schematics.
4) Finally, I've learned a lot and that's always fun!
Of interest to readers with other rigs were Paul's final words " ... don't
forget that your efforts to repair the rig will NOT effect your warranty!"
(In a few days I'll be posting pictures of the Argo V surgery on my website
for those that may be interested.)
73,
Rick
VE7ASR
Web site: http://www3.telus.net/ve7asr
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