[TenTec] No SSB TX from Omni D

[Jay Eimer]

Guys,

I have recently acquired a Ten-Tec Omni D Rev B transceiver.  Everything
seems to be working fine, except I can't get any drive on SSB.  CW power out
is fine (in fact, possibly too fine, as I can peg a 200W meter).  But when I
key the mike in sideband, the meter tweaks up to about 10W, then slowly
fades to zero over about 1-1/2 to 2 seconds.

At first I thought I might have had a bad mike, since it doesn't match the
radio.  But I've since tried 4 others (none known to be good, but what are
the odds....) as well as one "modern" mike, that's only 600 Ohm, but wired
through a step-up transformer to 25K Ohm, and I do know that it is good.
All the mikes will key the radio in VOX, and hold it keyed as long as I'm
talking.  However, none will light the ALC light, no matter how high the
drive is turned.

Checking in the manual, I decided to check voltages on the SSB Gen board
(part 80499).  Here's what I found (only the discrepancies noted - assume
the rest checked normal).

Pin Voltages:
    SB-N Tx    CW 13.5 instead of 13.8 and BFO 5.0 instead of 5.7
    SB-N Rx    BFO 5.0 instead of 5.7
    SB-R Rx    BFO 5.5 instead of 5.9
    CW Rx        BFO 5.0 instead of 5.9
    Lock Rx        BFO 5.25 instead of 5.8 and T 0.7 instead of 6.6 (biggest
error).  The rest are within 0.1v of the book.

All of the transistors check out okay.

The ICs, on the other hand:
IC1 - Tx - pin 1, 4.4. instead of 5.4
        pin 2, 4.4 instead of 2.3
        pin 3, 4 instead of 0!!!!
        pin 4, 0, normal
        pin 5, 1.5 instead of 5.4
        pin 6, 4.4 instead of 7.7
        pin 7, 4.4 instead of 6.6
and pin 8, 8.2 instead of 7.7

IC1 - Rx - pin 1, 4.4 instead of 5.5v
    pin 2, 4.4 instead of 0
    pin 3, 4 instead of 0
    pin 4, 0 instead of 1.6
    pin 5, 1.3 instead of 5.5
    pin 6, 0 instead of 8
    pin 7, 4.5 instead of 0
and pin 8, 8.2 instead of 8

IC2 - Rx - (disclaimer, I was unable to find the "mark" for pin 1 as
indicated by the manual, so this is a best guess based on the position on
the board - I would have hoped the measurments would line up....)
pin 1, 8 instead of 4.1
pin 2, 0 instead of 4.1
pin 3, 8 instead of 4.1
pin 4, 5.5 instead of 0
pin 5, 0 instead of 3.6
pin 6, 0 instead of 4.2
pin 7, 0 instead of 4.3 and
pin 8, 5.5 instead of 8v

Any ideas on what part might be bad?  Caps?  Somewhere else besides the SSB
board?

All help very much appreciated, as I just recently got my upgrade and I'm
desperately trying to get on HF.

Thanks,
Jay
KD5WLX