[Elecraft] Re: KPA100 Upgrade to revision D

[wayne burdick]

Hi John,

The present changes are intended to eliminate the large RF choke that 
had been positioned near the antenna jack (100 uH, RFC10). Some 
builders had difficulty positioning this choke correctly, and in rare 
cases this could lead to feedback between the amplifier and the 
40-meter band-pass filter on the RF board.

With the choke out of the circuit, the amplifier should never have any 
feedback on 40 meters.

If you don't have any issues with the amplifier there should be no need 
to do the mods.

73,
Wayne
N6KR

On Nov 10, 2006, at 5:06 PM, John Reiser wrote:

> Hello everyone,
>
> I just downloaded and read the KPA100 upgrade instructions to revision 
> D.  It is available now on the Elecraft website.
>
> What is missing, for me anyway, is a detailed explanation from 
> Elecraft exactly what these changes are designed to accomplish.  I 
> have two pre-revision-D KPA100s that work fine as far as I can tell.
>
> An explanation from Elecraft would go a long way towards motivating me 
> to fix something that doesn't seem "broke."
>
> Can anyone illucidate?
>
> 72 and 73,
>
> John, W2GW
>

---

http://www.elecraft.com