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To: "Bill and Liz" <>
Subject: Re: [Amps] THE SKINNY ON MY AL-82
From: "Jim W7RY" <>
Reply-to: Jim W7RY <>
Date: Thu, 18 Dec 2014 07:14:01 -0800
List-post: <">>
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.

Jim W7RY

-----Original Message----- From: Bill and Liz
Sent: Thursday, December 18, 2014 6:49 AM
Subject: [Amps] THE SKINNY ON MY AL-82

I recently tracked down the ham who had done work on my AL-82 as well as a second one purchased at the same time by another fellow who was forced by health out of ham radio. I learned that right from the get go both amps had parasitic problems and hardly a day would go by without one or the other having an “event” (hence the original owner had two of them!). These amps date from the 90s-perhaps they were of the initial design before changes started being made.

The Measures parasitic retro kits were installed in both amps and the problems immediately disappeared. Both amps today have the same minor problem on 10M: extreme heating, discolouration and distortion of the 100 ohm paralleled resistors in the suppressors but no parasitic events.

From this information it would appear that I would not be wise to re-install the original suppressors, and, since I seldom run the amp over 400W on 10M anyhow, that I should “let sleeping dogs lie” as it were.

Thanks to all who came forward with ideas and advice.

Bill VE3NH
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