Andrew VK3BFA wrote:

1. If there was a faulty batch of tubes, they would have been cleared
out by now - MFJ would have had words with Amperex, so they can be
eliminated as future fault causes.

2. is it a design error - possibly, but then again MFJ would be aware
of it by now and offered a correction - this company would not stay in
business in the Amateur Radio marketplace if it didnt.

3. The filaments high at 5.7 volts - it can be safely assumed that MFJ
would have set them up properly at the factory


How can it be safely assumed? You seem to be assuming too much of the
manufacturers. Their business is not humanitarian relief - they're in
this for the money. They would certainly not be the first one to make an
amp with the filament voltage too high.


73 .... WA7AA

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