[Elecraft] KPA100 Mod kit experience

[Vic Rosenthal]

I just installed the new KPA100 mod kit which allows the SWR to reach 
2:1 before the power starts to fold back.  I wanted to mention a couple 
of things:

1) The mod involves replacing a number of 2 and 3 watt resistors on the 
KPA100 board.  These resistors have fat leads which fit relatively 
tightly in the holes.  You need to be very careful about removing the 
old ones gently, cleaning the solder out of the holes thoroughly, and 
inserting the new ones.  If you yank an old one out or force a new one 
in, you can lift a pad much more easily than with smaller components.

2) The instructions say to replace the thermal pads only if they have 
come apart.  Mine had a mottled appearance and looked like bits were 
missing -- but they were fine, as I discovered after removing them!  I 
had ordered the replacement pads with the mod kit so I didn't waste any 
time, but it was unnecessary.

3) If you do replace the pads, make sure you retighten the hardware 
after 5-10 hours of use as described in the KPA100 manual.

The mod works.  I have an 80/160 meter antenna with a somewhat narrow 
bandwidth, and I was able to get full power up to about 2:1, as spec'd.

Now, I wonder what else is different in the new firmware -- my old one 
was 1.06 and the new one is 1.09...

-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco