[Elecraft] K2 10W PA problem

[Kevin Hibbs]

Guido,

I had a similar problem with a HiCurr a couple years back working on a
friends K2.  The problem turned out to be R67, a 2% tolerance (blue)
resister that controls feed back to the RF power control; which was
burned for some reason.  I replaced it and fixed the problem.  If the
noise blanker is installed this resistor will be hard to see because
it sits under it.  I did not have a problem with increasing current,
but it is worth a quick look just to make sure this is not the
problem.

Best of luck!
73,
Kevin
KG4TEI


On Mon, Jul 12, 2010 at 4:28 AM, Guido Tedeschi <guidoted at gmail.com> wrote:
> A friend asked to me to repair his K2 10W which has a strange problem:
> too high current in TX (1.2A even with 0.5W) and current that
> increases during key-down until HiCurr protection.
> Already changed the 2 x 2SC1969 PA transistors and re-winded the
> output transformer, but nothing changed: the voltages on PA and driver
> seem OK, the power from driver and the power output remain stable
> during key-down, but the current increases...
> What could be the issue?
> Before spending more time on troubleshooting, has someone had and
> solved the same problem?
> Thanks and 73
> Guido, ik2bcp
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