Yaesu FT857D strange behaviour

The place to talk about specific amateur radio equipment and all types of accessories, fixes, repairs and modification.
Post Reply
2E0BSL
Regular
Regular
Posts: 44
Joined: 15 Oct 2024, 12:07
Call Sign: 2E0BSL
Has thanked: 1 time
Been thanked: 4 times

Yaesu FT857D strange behaviour

Post by 2E0BSL »

My FT857D has been intermittently resetting on power up. Some years ago on a field trip, it had it's polarity briefly reversed. I suspected a partially damaged reverse polarity diode but cannot find one on the circuit diagram. Any ideas? Thanks in advance.
User avatar
MrWeetabix
Admin
Admin
Posts: 16304
Joined: 26 Aug 2008, 13:34
Call Sign: 26TM175
Location: Gateshead
Has thanked: 9 times
Been thanked: 5 times

Re: Yaesu FT857D strange behaviour

Post by MrWeetabix »

does it work normally other than it resets on power up? Kinda sounds like a memory battery if so. I am basing that on no hard facts by the way. haha
26TM175. OP: Craig. QTH: Gateshead IO94EW. Also 163TM175 when mobile in Wales 8)

Transmission1 on Facebook http://tinyurl.com/TM1onFB | Tango Mike on Facebook http://tinyurl.com/TangoMikeFB |
2E0BSL
Regular
Regular
Posts: 44
Joined: 15 Oct 2024, 12:07
Call Sign: 2E0BSL
Has thanked: 1 time
Been thanked: 4 times

Re: Yaesu FT857D strange behaviour

Post by 2E0BSL »

Thanks for the reply. After swapping out my PSU (Palstar PS30m) I found a known problem with the PSU. It doesn't like FT857D when powering up and goes into oscillation, causing problems with other radios also. For anyone interested

https://www.qsl.net/pa3fqh/ep920/ep920.html
Post Reply