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- čas přidán 22. 06. 2016
- This video documents the troubleshooting process I went through to repair a Yaesu FT-817ND QRP all-mode HF/VHF/UHF transceiver. The problem was that the unit would not transmit on SSB, AM or CW modes of operation. Transmit on FM, Digital and Packet were fine on all bands, and receive functionality was fine on all bands and modes. The video documents the troubleshooting process, but does not show the bench work (scope and DMM measurements). This repair wouldn't have been possible without the great information from Clint, KA7OEI, and the fantastic information available on his FT-817 resource pages:
www.ka7oei.com/ft817pg.shtml
Hi Alan, this video was excellent as it clearly shows the research and detective work to be done to trace down a problem in a modern radio. May be it becomes more clear that a repair can't be argued over a component price which is very low. It is rather more the deep knowledge and experience and labour which make a repair like this possible! And by the way it was absolutely NOT boring! Thanks for sharing and thumps up! 73 Peter
Good job, I think you made the correct decision with your approach for this video. It can be quite the challenge going from the block diagram to the schematic then to the PCB to find what you are looking for with the later being the most difficult for me... it is always a big game of where is Waldo. Thanks for doing this kind of thing and keep them coming.
Google took me to the KA7OEI pages a long time ago as he really has a lot of info on the FT-817. It's good to see such a keen interest in a single radio. Lots to read and think about when playing with this radio. Interesting video but hopefully I won't have to refer to it for my 817 as so far it has been great!
I think the way you went through the troubleshooting and explanation was great. Sometimes it is just not convenient to show every bit of the repair. Those big schematics are really nice also. Was doing a lot of that at one time. The Amscope I bought is really helping out to see all that tiny stuff. Very nice repair Alan.
There's a lot of value with this video! The steps you took, the fix and having the Sam's printed largely, sure beats printing one small page at a time then taping together, especially at about the same price or so! :)
Logiically i didn't see you shift to either side band transmission therefore the unit may only be transmitting on one side . The question is were both side bands affected originally?
Hi Alan, Boring? Not a chance. Seeing parts measured and replaced is X.XX amount of dollars. Things learned from the thought process, circuit description, showing the signal path and communicating with others, “PRICELESS”. Of course you know this. :D) Plus the tips you passed on from this repair. Great video! 73
Very impressive. Those rigs including my 817 are very complicated. I lost a final driver but I was afraid to get in to that very tight place and replace it, so I sent it off, so small but yet so complex. W4GSM
Any idea what may have caused the problem? Could the radio have been shocked physically as in a fall? Just wondering your thoughts. Great video. Well done. Thanks for sharing!
This must have been repair for a friend. Knowing that you have $500k knowledge and spectrum analysers costing $40k it would be cheaper just to buy a new transceiver than to pay for your service. Great diagnostic process showing in-depth understanding of matter in question and preference to using mind rather than solder iron. You impress me again and again Sir.
Great video! Understanding the process is by far more interesting than seeing you soldering. :-) 73 (LA6GHA)
Another excellent video, my own FT817 has never failed, however a friend has had his fail a few times. We replaced the PA section but it went back to Yaesu when something else went wrong. Sometime later it seemed to have an issue on 80m with strange ALC readings and slumping power output.
I recently had a power surge on mine and the tech repaired that part of the unit but says the radio receives but won't transmit, trying to figure out 2 things 1. if I reboot the radio will it come back or 2. if there is another component that might be damaged> any suggestions
Hi Alan, sorry but silly question here: looking at the scale on your wattmeter, it appears that output was actually over 10W, but in each case you say it's just a touch over 5W. It appears that you're dividing by 2? Is that just a known function of that particular meter, or is there something I'm missing? Thanks and 73 de AC2OI.
When you speak of component level checks using a multimeter, do you have to lift a leg of the component? If a component is bad, or maybe even not, I would assume you would be reading circuit resistance via whatever path of least resistance it finds. How do you know you are reading THAT component?
And that's why guys send you their radios for repair! I watched and listened to this waaay over my head analysis video. Reminded me of calculus class in college. I was lost there, too! N0HRM
TNX Alan for another great video !
That's a very impressive schematic! I consider it a piece of art. I've certainly never designed anything that complex, but even with the simple stuff, I tend to separate each block on the schematic and use netlabels to connect them.
That was is a really dense schematic, you would have to be careful following the circuit path. That was the first time I saw a smd transformer, looks like a nightmare to align. Was there any component mask on the board at all I would think not. Great to see your techniques for repairing equipment Alan, any review of the new AWG4162 in the future? Cheers.
Very Very Good Alan, was waiting for this one, as A owner of Ft817 and made Mods updates to mine was very interesting as I to heard about the IF can problem and from other users as well, seems a lot of bad Cans ? Yes Clint is a blessing site and lot effort he put into it.Also do same as you on the Drawing sure helps on eye site ah ? lol lol and not having to flip pages lol .Thats Alan good a Good Understanding Video. like always Thanks for the effort 73's Alan