No need to worry about IC Q106, all that section is working, else you would not have the megacycle lock light flashing, this is the mixer chip for the Wadley loop, it takes the VFO and the harmonic gen products and converts them to the 52 meg IF. The output of this IF strip is rectified and used to light the LED, so this signal is present and correct.
The problem seems to be upstream from the second mixer, between this and the first mixer. Place a short wire to TP103 and see if any signals appear, this will eliminate the RF amp and front end tuning.
On Sat, Apr 8, 2023, at 11:05 PM, Bob W8RMV wrote:
As the saying goes, I am self taught & I had a bad teacher.
I got the scope out (means I am desperate) I can see the 1st & 2nd ocs.
I can see the lock unlock working & the comb freq on the scope.
I pulled Q105 2nd Mixer & Q104 and both tested fine.
But I see very little at TP107 coming out of the premixer IC Q106.
And I do not see the 3MHz coming out of the good Q105 over to the IF/AF board.
So I am thinking it maybe that IC Q106 or maybe someone messed with the alignment.
Thanx for the comments.? The slog continues...
--
-Bob
