Is my FT-857 on the blink?

[RadioBOB]

Yaesu have already replaced all internal board and workings and a new head unit for my FT-857
after a major memory flaw it had remembering anything. Its been ok for a year or so but now..

I noticed a few weeks ago my FT-857 just reset itself when I turned it on,
it was only a partial memory reset, still annoying, then I was playing with Digital Modes PSK31 SSTV
and I use 2 leads a USB to DAta port and another one for the other data port to 2 x 3.5mm mono plugs
Audio In and Audio Out to the PCs audio in. Ham Radio Deluxe is working well, MMSSTV all ok, then
while I was pushing the PTT button and checking SWR on a clear frequency (swr was perfect) the Radio performed a full factory reset,
even overiding my SoftJump2 Mod, really annoying, luckily I had used FTcommander to remember the 17 memories I had plonked back in after the 1st reset but without alpha tags, and that wasnt easy either! FTcommander had to put them back in one at a time and MW press for 1sec select next channel then Function key for 2sec's, wish I could change speed to 0.3sec to access Full Menu. So why isit reseting? one thought was power coming from the USB lead into the radio but it was not connected at the computer end only the radio end. strange. A service must be due.

Theres lots of wires about could it be some kind of static feeding back up the cables?
Could it be the lead behind the head unit? I removed all cables and re-seated them all. Seems ok for now.

[RadioBOB]

Yep its deffinalty having Eprom problems now, could it be dust? badly seated chip? checked all head unit connections did a RELAY CLEAN by HOLDING BAND UP DOWN while POWERING UP, set meter to Read SWR but refuses to budge from reading PWR so its off to Yaesu in Hampshire for a service as soon as I can afford it. Its a shame but Yaesu do give a 2year warranty after the 1st year they replaced the headunit and radio insides so virtualy got a new radio, and ive been using it daily for over a year so its probably due a service.

[hamman]

Sounds to me as if you have RF getting back into the system as it happened when you had hit the PTT.
Are all your connections to the PC fully screened and isolated, not direct connections but via isolating transformers or opto-isolators?

Had a similar issue my self which was down to dodgy screening.

Regards

John

[RadioBOB]

"Sounds to me as if you have RF getting back into the system as it happened when you had hit the PTT.
Are all your connections to the PC fully screened and isolated, not direct connections but via isolating transformers or opto-isolators?

Had a similar issue my self which was down to dodgy screening."

From my PSU i have leads for FT MEter , FT857 , the Kenwood TH78e , never had a problem with the leads before,
No isolators between the radio and the PC, its a small samsung netbook, one theory I had was one of the USB sockets is also for charging so I thought it maybe feeding to much voltage back into the radio, could well be RF feedback on the TX, I'll do a complete re-route try to tidy it up as best I can, thanks for the tips! I just got latest copy of HRD and cant connect at all now :/ ah well I did get satelite tracker running ok this time, great program. must sleep now.

[hamman]

I would break it down. Remove everything that you don't need, extra wires equipment etc, just keep the basics. If it all works, then add bits back one at a time untill you find the culprit.

" I thought it maybe feeding to much voltage back into the radio,"
If you exceed the input voltages then that would normally let the magic smoke out, and that’s a bugger to put back

John