12 A 250V Fuses
8A 250V Fuses
The Ameritron AL-811A and AL-811H are very
reliable HF Amplifiers. I own one of each. But the Chinese
made 811A tubes are not very reliable. When one of those tubes goes...it
can go with
a flash and always takes out a fuse or two...and sometimes blows a protection diode
and a meter lamp too.
This is very common and has happened to me at least a half dozen
times over a dozen years.
In order to figure out
which tube went bad...you normally have to take all the
tubes out (careful...high voltage!), and
test them in the amplifier one at
a time. The tube that blows another fuse when you turn the amp on, is
the culprit, unless there are other problems. I use the same
method to test used 811A tubes I come across.
These are plentiful and cheap, because often, when a tube goes bad, hams
replace all 4 of them and put the others on the shelf where they stay
until the tubes show up at a hamfest or on Ebay. I typically find
that for every 4 tubes I get used, one is bad. In any case...
up going through a lot of
I got tired of running
out, so I bought good quantity of the
8 A 250 Volt fuses, 12A 250V fuses, and 1N4007
1000V (meter) protection diodes. I won't run out any
time soon; in fact I
have more than I need. The trouble with trying to get these retail
online, is that the shipping charges high. So...
If you need replacement fuses, or diodes, contact me
I'll send you (5) for $6.50 postpaid while my supply lasts.
Let me know if you come across a
cheap source for those little frosted incandescent meter lamps.
Bill Patton, WY3AWest Chester, PA