--- In ham_amplifiers@..., R L Measures <r@...> wrote:
On Oct 30, 2006, at 1:43 PM, pentalab wrote:
it off... all was well. If that had been the INPUT
insulator,,, I
could have easily smoked the 3 A diodes,
RICH SEZ.... 3A diodes will do 200a-pk. Not many HV transformers
will. The original Plywood Box amplifier used 150a-pk, 2.5A avg
diodes in a FWB > and the diodes survived at least 4 flashovers to
gnd without benefit of a HV fuse.
### All as you are doing is stressing the hell outa the diodes.
The 5th time you might not have been lucky. For a 14 kw amp, like
ur plywood box.... you shoulda been using 1 kv-6A diodes [400A
surge] like a 6A10.... the 0nly diode worth buying these days.
### Rich, with that 40 A undersized breaker you have installed
in the 240 V line... it would be on the ragged edge on ssb to
start with... in a pre-heated condx.... a flashover would tip it
over the edge. IF you installed a 100-125A breaker, you could
have smoked the diodes. As is, with 14 kw out... ur line current
from the 240 V line would be 110 A on keydown... close to 55A on
ssb.
Later... Jim VE7RF
...
R L Measures, AG6K, 805.386.3734
r@..., , rlm@..., www.somis.org
