I have checked the archives for problems with the AL-80 and found some great
information. My experience on this kit is limited and wanted to confirm
some of the information.
The original problem was no output and in the standby position the valve
glows deep red. I replaced D17 (S/C) on the negative rail of the filter
capacitors which can be damaged by a 'gas arc'?
I now have about 150mA constant plate current and negative going anode
current, all in standby position.
The amp has had D17 changed previously and internally is in excellent visual
condition. It has sat in the same position since I bought it several months
ago and has not been used /AM! (Although it has been to VP8 on a DXpedition)
Just before the failure I applied 15watts of 10m RF when the amp was set and
tuned on 15m. Slight burning smell then no output.
>From what I have read it looks like I need to replace the 3-500z. Before I
buy a new valve (and cancel the kids Christmas presents) I would appreciate
further comments
Thanks
Jim MM0BQI
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