[Elecraft] K2 power out..

[Don Wilhelm]

Jean-Louis,

Only the Low Pass Filters are between T4 and the antenna.
If you have an antenna analyzer available, you can sweep the low pass
filters without a lot of effort.  A sweep done from the antenna BNC
connector can be meaningful even without taking steps to terminate the
filter inside the K2, but if you want to see good SWR values within the
passband, you should remove the W1 jumper and connect a 51 ohm resistor
between the right end of the W1 position and ground.  Check each band - the
K2 uses latching relays, so you can power the K2 on, select the band of
interest and then power off, the proper Low Pass Filter will still be
selected.

If you can do such an analyzer sweep, at least you can convince yourself
that the low pass filters are correct - and if so, look elsewhere for the
problem.

73,
Don W3FPR

> -----Original Message-----
>
> Bonjour,
>
> i am jean louis F5NHJ and i have a problem with my K2 #5371.
>
> Done on two weeks ( i'm retired) my K2... but got a big problem
> with power
> out.
>
> - I can't get more than 200 mW on all bands..
>
> - RX doing well and i have done one QRPP qso on 40 whitout problem...
>
> After tests during these two last weeks and dozen of email send to Gary
> (Elecraft team.. tks to him.!) :
>
> - I told him that it seems that there is a big cork just after T4.
>
> - Yesterday, i decided to change R50 - Q5 - Q22 - Q7 - Q8 ..  T2
> - T3 - T4
> .. rewounded and tks God i've got 4 watts decreasing very quickly to
> flashing 0,1 - 0,2  mw this morning here (only on 40 meters..)
> but Q7 Q8 are
> beginning to make French fries..
>
> - checked on TX all Q (exept Q5) and U from the Volts test sheet
> (grey one)
> page 17 RF BOARD and all sounds ok ..
>
> so i am lost and the little K2 calling me nights and days for help..!
>
> Jean-louis
> F5NHJ - REF & ARRL member
> http://perso.wanadoo.fr/f5nhj/
>
>