Yaesu FT857D strange behaviour

[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.

[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

[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

[Transwarp]

I'd be interested to see what amps the radio pulls at switch on using a car battery and meter to check.

[2E0BSL]

I'd be interested to see what amps the radio pulls at switch on using a car battery and meter to check.

I did some digging. The FT857 has got high internal capacitance which temporarily shorts Palstar causing linear PS30m PSU to oscillate. My FT950 also does this. It's a known problem with Palstar/ Manson series PSUs. Will have to mod PSU to stop it.