[Amps] Aplha 91b

[Helmut (DF7ZS)]

Hi there.

I had some problems with my Alpha 91b yesterday.
Maybe somone can have a good guess based on the symtoms I had:

10m band. Tuning with 10w resulted in about 800w out - as usual.

30-60w input resulted in solid 1k out - I remember it was more before
???

I tried to make the fine tuning with 70w carrier - did that before - but
the amp imidiatly went on "FAULT" !

The SWR was perfect on 10m - same results on 15m as well.

On 20m it produced some more output, but also here I was not abel to get
the red 1.5k LED to lit - as it usually does on all bands. :-( Also 75w
carrier results imidiatly in "FAULT" ....

I did not have a dummy load for high power available for any further
testing.

The IP did not WENT over 1A before the fault came.

Could it be that one tube is down ? 

73sss
 
Helmut
 
www.df7zs.de
www.skydive-video.de