[ADXA] BIC Failure

[Dennis Schaefer]

I learned a long time ago that you need the proper test equipment.  I have
a Bird wattmeter, a Fluke VOM, etc, but I came up with a need for something
I didn't have.

811A tubes are finicky and you can't push them too hard, particularly on
digital modes.  I don't use my AL-811 on digital modes at all, but have
been tempted, mainly with the VU4 who could hear very few due to a high
noise level.

Tom Rauch is the designer of this amp, and gives expert advice.  He said
many were sent out with inadequate fans, causing a lot of 811A's to melt
down.  He's correct, because a local here (not John or George or Charles)
has done it a few times.  When an 811A melts the plate, it often results in
a grid-to-plate short, which is, well.....less than optimum and sometimes
exciting and expensive.

According to Tom, there is one way to check the fan.  Put a BIC lighter one
foot from the air outlet, and if the lighter blows out, your fan is OK.  I
didn't have a standard lighter, so I tried the larger BIC lighter I use for
my charcoal grill.  The flame danced around but didn't go out.

$1.72 later, I had the proper test equipment - a bog-standard BIC lighter.
The amp blew it out every time.  Now I am confident my fan is OK and if I
burn up a tube it will be from improper tuning.  I know if I buy three
572B's, I will have adequate cooling for them.

Could I afford to just get a good amp?   Yes - a Mercury would be nice and
an Acom or OM would be fine.  I just want to do it this way for awhile,
mainly because people say it can't or shouldn't be done.

So the test equipment BIC yielded good results but only with some effort.
The personal BIC is anxiously waiting for Clipperton.

73,
Dennis/RZ/still at 1446 but expecting 1450 by the end of the weekend.
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