Phil Clements
410 VZ CR 4903
Ben Wheeler, TX 75754
----- Original Message -----
From: Phil Levin W2GE <w2ge@home.com>
To: AMPS <amps@contesting.com>
Sent: Monday, June 26, 2000 6:39 PM
Subject: [AMPS] Semi-OT Power supply question
>
> Little off topic but....I know you guys will have an answer for me.
>
> I have a backup 20 amp power supply that I normally run my packet 2 meter
> radio and a second two meter radio for FM simplex to rag-chew with some
> local DXers/FRCers.
>
> Anyway I used this power supply over the weekend for field day (nominal,
> it's only 20 amp rated, by Stabylex Elec. Corp.) and noticed on Sunday
> morning (after say 16 hrs usage) that one of the 2N3055 transistors was
> BURNING hot, the other one in that pair was hot, another pair were only
> warm. (total of four in the supply) My questions...
>
> Can it just be a bad transistor or is that just a symptom of an internal
> problem???? Is there something internal in the power supply that may have
> changed value to cause this transistor to be carrying way to much load; or
> do I simply just change the pair? Already picked up a pair at Active
> Electronics for $3.00.
Check the emitter resistors...sounds like some values might have changed.
If all is well with all of them, I suggest changing all of the 3055's (cheap)
and running under load to check foe equal heat in all the trannies.
GL!
Phil, K5PC
>
> Thanks in advance, de Phil W2GE
>
>
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