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i dont know that this would have damaged anything. someone correct me if im wrong here, but it would seem to me that if the input of the amp was connected to the antenna then there would be no RF present and the amp would not have produced any RF power. LC

also, if you are measuring at TP8, this chassis drops down 2.5khz on AM TX. so if you measured 35.005 on receive, you'd measure 35.0025 on AM TX. LC

If anyone is wondering what the two cut wires are in Nomad's 4th pic, that's factory and would go to the 10KC switch if they had included one on this model. LC

well a lot of this is above my pay grade, but here is more than you'll ever want to know about this subject: https://www.fars.k6ya.org/docs/Stearns_K6OIK-Conjugate_Match_Myths.pdf it gets interesting around page 28 where they start stating that Maxwell was wrong. LC

the FC-393 may look the same on the outside but it is completely different on the inside. gone are the easy jumpers to switch between different IF freqs. its all SMT now and using 0402 parts. It can be modified to work with a 7.8mhz IF but it is not easy and should not be your first attempt at...

are you guys moving to the full windings on both the primary and secondary of L4 and L37? or just on the secondaries? LC

man how many times have i searched the bench for that little screw that keeps the mic connector from turning in its body. thanks for this! LC

i was hoping someone like nomad would comment on the broadbanding. Nomad, i have heard that doing the L4 broadbanding trick will cause an impedance mismatch but i don't remember where i heard this. any chance you can assuage my concerns about this mod? LC

nope they're the same. they both use the TLR321 channel LED display.

well this place has a blue and an orange one. you might try contacting them and seeing about a red one. https://www.wearecb.com/cobra-753036-blue-led-cover-29ltd-chrome.html https://www.wearecb.com/orange-display-cover-for-c29wxnwst.html LC

When i encounter issues like this i get the scope out and start probing from the TX mixer output to the antenna jack. Sometimes one of the mixer inputs is missing, but most of the time its one of three things, a bad transistor, a bad tuning coil, or tuning issues. in cobra 29LTDs especially...

what are your voltages on TR16 in TX mode? do you have RF on the output of L17? (the L17 side of R55 would be a good place to check).

make a map of the TX voltages that go through that mode switch in each mode. note the source, the specific switch contacts and the components the voltages are sent to from the switch. now put the radio through its paces until the TX falls out, and use your map to see which voltage isn't making...

yes the feedline and its associated components are very likely the cause of this problem. the fact that the antenna is not being used for its intended purpose is also a problem. if her coax is over 10 years old, and im guessing in this situation that its more like 30+ years old then it's been...

got a model number for that realistic mic?

just wanted to add in that he's talking about adding the cap in series with the audio line, not paralleled from the audio line to ground. LC

the low pass filter will likely make no difference in your situation. Most likely she is not experiencing harmonics of your station interfering with her TV frequencies, it's simply RF overload. there is nothing you can do on your end, short of switching your hobby to shortwave listening lol...

Are you trying to align the VCO frequencies? the 34mhz ones? if so try using TP1, which is the junction of L20, R106, and R107. LC

that mod sounds like a talkback mod. if the radio works right now, you should be able to speak into the mic and hear yourself through the speaker with the switch in one position, and not in the other. the only other thing it could really be is a switchable swing mod. Basically switching that...

how did you check the SWR on SSB? LC