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Ubitx.net shows both capacitors installed. Sent from Mail for Windows 10

I am guessing here, but it seems like the signal generator is being loaded down by T2.? That might explain why you are getting better results when further up the LPF.? If there is a problem, then I

I redid some tests 7.150MHZ TP2 - 100uv gave 88mv p-p, 200uv gave 144 p-p - estimated those may be a little high given my frequency generator only put out 2.4v when set at 3.5v and can't measure just

Rob, Thank-you for verifying that the connections as shown do work.? Would you know the reason for C211 in the original circuit?? I would have thought that Ashhar Fahran would have only installed

Scrape off the toplayer of the underlaying trace and solder them there. Works fine. Rob PA0RBL

I have not yet tried to trace the signal path or a different microphone.?? Output power varies by band.? Strangely, it is lowest on 40M and 80 M, at 3-4 watts.? On 30M the power increases to over

Thanks Evan I was not understanding that but got it now.? Appreciate all the great info and ideas/diagnostics here. TP17 at 11.99 or so I could get a tone 480mv gave .1v p-p TP16 same freq at 50mv

Woody Did you every science out why the power seems low? Have you tried an alternate mic?

Too bad Evan. Your loss.

Your question made me go back and look at the picture.? L5 looks correct, as it is in the circuit as was the original (L5 and C215 in series with the filter).? L7 is directly connected to T4,

I tested with an RF Explorer SA and found that I had the harmonic issue on 40m, even on ssb.? I did not see the issue on 20m or 10m.? I have not had any success with those bands, mostly due to

Dave, By the time the signal from the antenna gets to TP17, it has been converted to the audio on a 12mhz carrier.? Said another way, the signal by now has been converted to 12mhz +- the audio tone,

AT 60mV you should a really loud sound from your speaker. Check all the resistors and report on DC voltages at the audio transistors. Raj

TP 16/17 should be around 12 Mhz regardless of the frequency setting on th ubitx ...all else is filtered out by the 12 Mhz crystal filter Jim

Injecting 1khz tone 2.4v at pin 3 of q71 (should feed into q72 and q73) produced .1v p-p

Also interesing at the base of Q71 injecting 1khz signal at 60mv gave a .1 mv peak to peak signal but I could not hear any tone on the speaker.? It wasn't until injecting 300mv could I faintly hear

I checked the boards solder joints with a magnifying glass but it's really hard to tell.? probably need to find a way to test specific suspect points. I tried to check the toroids in the load pass

K3 pins 12 and 14 get a tone for continuity. Tp21 shows 10.85k ohms to ground.

The Koss cs100 has an electret element and works well. I have one that I have used. Someone else on this board put me on to it. They are now about $20, but not long ago were much cheaper.

Sorry that was for Q70