[Elecraft] PA PROBLEM

[Don Wilhelm]

Eugenio,

Try these steps first:

1) Measure the resistance between RF Board D9 (cathode end) and Control
Board MCU (U6) pin 2 - it should measure 3.45 ohms (or very close to that
value).  This verifies that the VRFDET signal can reach the MCU.  If you
find a much higher or lower resistance, find the fault first.

2) Check all toroids for the proper number of turns and well tinned, well
soldered leads (the solder joint should look like a mountain, but not a
volcano).  Particularly check T1, T2, T3 and T4.

3) Check all components for proper values and all diodes for proper
orientation.

4) Under a magnifying glass, check all soldering carefully, then recheck all
soldering, and finally, check all soldering.

Component failures are rare unless the components have been subjected to
abuse, so double-check all your work before concluding that a component has
failed.

73,
Don W3FPR

"Life is what happens when you are making other plans"
(John Lennon wrote it in a book, Mike Cross used it in a song - I don't know
who was first)

----- Original Message ----- 

> Hello to all:
> My name is Eugenio and my call is EA7HG
> I built a K2 (s/n4133),but i have high current (5A) when i Tx.
> See on manual and say bad PA transistor.I change the 2X2SC1969 for others
> new and have the same problem.
> I need help.
> Thank you all
>