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Yaesu FT-757GX (mk1) TSB?

Cable Guy

Growth must be chosen again and again.
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Dec 29, 2010
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I'm recapping my old Yaesu HF rig and wondered if there are any service bulletins issued or any known issues that I should address while I have it gutted, as this radio is a chore to remove boards.
 

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Sorry, I goofed up, I typed 747 when I have a 757. Trying to figure out how to change it. I found the service manual for mine and it lists a few service changes but mine is a newer serial number so not needed. I recapped it and reassembled it, going to align it.
 
Thanks BJ, those are modifications I didn't know I wanted, but I have to have them. I'm going to assume these rigs were well thought out and engineered, and they are solid so not many issues to address, especially later in production.
 
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I didn;t read the tech manual above or watch the vid, but I've owned about 10 of these and the best upgrade you can make on these is to remove that soldered in battery and extend it with wire and use a replaceable 2032 covered in shrink tube. Also, there's a heat sensor used to to turn the fan on and off that needs to be removed, cleaned and have new thermal paste applied.
 
I didn;t read the tech manual above or watch the vid, but I've owned about 10 of these and the best upgrade you can make on these is to remove that soldered in battery and extend it with wire and use a replaceable 2032 covered in shrink tube. Also, there's a heat sensor used to to turn the fan on and off that needs to be removed, cleaned and have new thermal paste applied.
I was just eyeing that old dead battery wondering what to replace it with, so a 2032 huh? I can manage that, thanks Greg, and the point about the the thermistor is also noted as it takes a while for the fan to turn on, heats up more than I'm comfortable with. It does spin up at boot. I haven't recapped the 100w power board yet as the 1000uF cap in the kit is too tall.
IMG_20250416_164309818.jpg

I need to find a shorter version with some girth to it.
 
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Also, they use a little bulb on the board as a fuse for the receiver. Have no idea of the logic behind this, but it may not be a bad idea to replace the bulb or your receive may go out.
 
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Found this article noting some faults to look for.

Also, I see the trimmer caps can become problematic and drift. This unit shows no signs of drift so thinking I'm okay, just noting for future service. The switching diodes into the bpf are also prone to leakage so I may proactively swap them.
 
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Found this article noting some faults to look for.

Also, I see the trimmer caps can become problematic and drift. This unit shows no signs of drift so thinking I'm okay, just noting for future service. The switching diodes into the bpf are also prone to leakage so I may proactively swap them.

I had one of these way back mid 90s that would do something very strange. Never figured it out before I sold it. Had one that if I turned RF gain down, it would turn down the RF power at the same time. Weird.
 

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