Date: Thu, 18 Dec 2014 07:14:01 -0800
From: "Jim W7RY" <w7ry@centurytel.net>
To: "Bill and Liz" <magoo@isp.ca>
Cc: AMPS <amps@contesting.com>
Subject: Re: [Amps] THE SKINNY ON MY AL-82
Is he (YOU) SURE it was parasitics? More likely hot switching of the
amplifier T/R relay. This causes LOTS of problems that folks THINK are
parasites.
After I install my QSK system into amplifiers, the arcing completely STOPS
because the relays are no longer hot switched.
ALC overshoot spikes also cause arcing in amplifier capacitors. Mostly
Kenwood has ALC overshot including the TS-590S.
Although, the Icom IC7410 has ALC overshoot problems on SSB. Which is
repaired by Icom for free. Although only the units made before mid 2014 are
affected.
73
Jim W7RY
## The AL-82 is known as the...firecracker ! It’s a parasitic prone amp,
right out of the box.
The Rich measures suppressor will solve the parasitic issues 100%.... except
his suppressors
run hot on 10m. Hotswitching wasn’t the issue... but will make it
worse..ditto with overshoot.
A conventional suppressor will work, but the trick is finding non inductive
resistors these days.
To tame the parasitics with a conventional suppressor, it requires slightly
more L.... which will
cause the resistor to run warm / hot on 10m. A 10/15 watt globar is the
real solution...works good.
Then used wide silver plated strap for the suppressor coil.
## KM1H used a method, with caps in series with new style mof resistors... to
cancel out the xl of the
mof resistors. 2-5 x 3 watt mof resistors in parallel will provide enough
heat handling capability on 10m,
but will require 2-5 x series caps. If you can find some old style Carbon
comp resistors, 2-5 of em in parallel
will work. A single 10-15 watt globar is the no brainer solution. Or leave
the rich M suppressor in there,
and don’t operate it on 10m.
## KM1H has had a lot of experience with that amp. Hopefully he will chime in.
Jim VE7RF
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