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Been in a few FM transmitters in my day, had a rookie tech get mad at one and throw a wrench into the power supply not expecting it to come back and hit him in the face, took his teeth out. Yes anything can be made to work again and my philosophy is if it worked from the factory no reason it won't work again today.
So that being said the replacement tuner has resulted in little progress, it does pass a signal from the little UHF input RCA on the side thru the tubes and down to the IF input on the chassis however that's about it. All the solder connections in the tuner itself are good, the 6HQ5 RF amp and 6HB7 mix/osc check good on the tube tester but I bought some NOS tubes on the 'bay and will give them a try upon arrival. My supply of these is limited to a few in a storage tote and while they do check good on a Heathkit IT-17 something may very well be "off" enough to cause a problem. I've had the IT-17 since middle school (1982) and trust it however being little more than a "diode test" of the tube there could be something like a burnt grid wire or a spot on the cathode that wouldn't show on the meter yet could kill the local oscillator. I got the IT-17 new in the box unassembled at the Medina MN hamfest for $10.00
Until then the remaining repairs will be done using an outside IF source provided by one of those tuner units that was part of a Panasonic portable VCR combo, still need to iron out the weird phasing and chroma shading issues that I suspect might be coming from the TAC board. If you remember these had the "Total Automatic Color" feature that basically added more red & yellow giving everything an orange cast, great if you like burnt orange shag carpeting but it's not my favorite and I may just bypass the board all together.
Will post more when I can.
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