Does the FT817ND Power Amplifier PCB fit and work in early FT817?
After on-summit trouble with my 21-yo FT817 during the Lake District Weekend (September) some tests at home suggested that the power amplifier has gone defective (maybe one of the two push-pull transistors). I measured the FT817’s RF power on all bands into a dummy load and HF/VHF/UHF antennas. On the 5W setting I’m getting 0.9-1.4W on the HF bands, 0.8W on 2m and 0.3W on 70cm on CW, SSB and FM.
I contacted a reliable UK dealership who said the original PA PCB was no long manufactured but would find out if the more-recent FT817ND PCB could be retrofitted into my very early 817. As the days tick by and I’ve heard nothing, I’m beginning to fear the worst.
Does anyone know for sure (as opposed to guessing) if the 817ND PA PCB works in early 817’s?
I was going to offer you £75 when you had installed the new PA board and it was still not up to snuff.
Can I suggest you contact Yaesu UK direct. They will happily sell to end users and the customer service is second to none. 01962 866667 or email service@yaesu.co.uk.
I wonder if Yaesu UK also offer a service to fit and test it. After I cocked up wide-banding my FT857D for 60m and having watched a YouTube video on replacing the PA PCB, I no longer trust myself to do.
I’m pretty certain I didn’t abuse my 817 recently - like tx’ing into an open circuit for ages - so, hearing that a few others with vintage 817s have suffered the same fate, makes me feel less guilty, and that the failure was probably an age thing.
That’s odd. I also charged the internal battery prior to the LD SOTA event. Coincidence or what?
TBH I think it was PA self oscillation that saw them off in the original PA units and I feel if yours was susceptible it would have committed suicide by now.
Talking of prices… there was an 817 complete apart from the tiny rubber duck extension, boxed, manual, PSU etc. etc. Battery was dead but it was clean and “100% working” with the asking price being around £200 at the Galashiels Rally last Sunday. I should have punted and put it straight onto eBay for a quick £175 profit assuming it did work. Likewise a very clean 857, boxed etc. went for £75 cash at my own clubs last junk sale. It was 100% apart from very low output on 2m, as it was from a trusted source, I should have bid, bought it, fixed and punted on eBay for £500-ish.
I know I’ve um’d and ah’d about selling the 817 (even on this reflector) but it still performs an important role - portable 2m SSB/CW and 6m - that I can’t or won’t do with my KX2 and FT857D respectively.
When my ft817 (original model) final stage was replaced with the ND stage, I was asked whether I wanted to increase the power output to 6w. A quick calculation shows that the difference is less than a db, so not worth doing. No-one could hear or even measure the increase. So, keep it to 5w and enjoy longer life.
I did exactly this with my very early FT-817. It works completely normally. The whole experience dealing with Yaesu on the phone was great.
Fitting the board yourself is a little daunting but all you really need are some fine screwdrivers and a decent soldering iron. There are articles and videos on the Internet explaining how to do it. Have a read/watch. The only slightly tricky part is adjusting the bias as it’s not linear.
