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Just and update. There was a whine that on the radio The bfo was off by about 2000 hz. I copied the bfo frequency off of one of my other machines and it only needed a small touch up from there.

Perhaps 1 or 2 dB loss through the LPF at L1,2,3,4 ? 6dB loss through the mixers ? Maybe 3 or 4 dB loss through the two crystal filters ? And around 10 or 12 dB gain through the 45mhz amp, 16dB

Wow thanks everyone for all of the great info and ideas to investigate this further.? Some great details and avenues to investigate further. I am using the stock software.? (A separate thread I need

Assuming your signal generator can correctly inject the levels shown in the chart, you should get rational results here regardless of the different frequencies. Namely,? ? Perhaps 1 or 2 dB loss

On second glance, those measurements show a 30 dB loss from TP16 to TP17, not a gain. Also a 20 dB gain from TP14 to TP16, going through the 45mhz filter and D3,4 mixer. That one should be on the

different frequencies .... Jim

Hi, I have not looked at the schematic. This problem reminds me of the failure I found in the front end of a different radio. There was indeed a broken winding on one of the inductors, one of those

I'm not sure what to make of Jim's measurements. YMMV indeed! Two measurements at TP1 with a difference of 30dB? Somewhere between 10 and 20 dB of gain or loss from TP2 to TP1, depending on which TP1

So ....What I did on my "seasonal vacation" Quick and dirty trace thru V3 ubitx ...Test points correspond to V4 locations ... Set ubitx freq to 7.152 mhz dial indication ...Maybe off a little as WWV?

I read (and had the issue myself) where the USB and LSB seem to get reversed.? This was related to the LO being off.? It was solved for me by going back to the default after setting the BFO and then

Actually I redid the BFO adjustment to zerobeat and at 11996.6 sounds better for 1khz, and at least the conversations are intelligible better now.? So that is a bonus. (conversation is still faint)

Thanks I see as folks suggested? Q10 is past the first mixer of clk2.? That still doesn't explain why injecting at L4 is heard significantly less than injecting at L1.? I would think the closer I

Evan, indeed bfo adjustment is a factor, my recent v4 was way off. Maybe this could he in play here. Dave, good work using your diagnostic equipment. I would first he suspicious that the automated

Sheez, Terry, Sorry your world is closing down. Sounds like the song, "Told to work, too young to die." Best wishes. 73 Sent: Saturday, December 22, 2018 at 2:07 AM From: "terry hughes via Groups.Io"

Please understand that I am not an expert on this topic, or board.? I do have a background in Electrical Engineering, so have some training, though not in troubleshooting (other than for industrial

Why I went down this route is due to low signal can barely hear anyone.? So I figured I'd try some tracing.. My understanding is 50uv (volts) should provide an s9 signal.? My signal generator lowest

Ok for the earpiece. If I find one I will tinker with it. I agree that the ubitx sounds ok (a part from tx IMD figures not excessively good) with the condenser type and unlikely it will sound better

OK, I reread your post.? ?I do see that you are before the first mixer testing on the low pass filter (c200-204).? I would assume that it would not be linear at all.? even though you are getting

Better thinking is that the carrier-balanced 1-KHz signal is heard farther back toward the audio section, after the BFO has done its work. Bob — KK5R --------------------------------------------

Dave There is gain distributed rather evenly so not sure you are seeing anything unusual. Unlike a commercial rig with gobs of AGC, this rig requires using the gain control. Please evaluate into a