K2 - Question on control board

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

K2 - Question on control board

jwin2485
I'm in the process of upgrading my K2/10 (SN 1057) to a K2/100. I am also finishing up the KAT100 tuner and have a question. The tuner instructions state to remove C44 from the K2 control board. I have a Revision A control board without a C44. It also states that if this is the case, a capacitor may have been soldered directly across R7. On my board, a resistor is installed at R7 (no capacitor). Do I leave R7 in or take it out? Incidentally, I did all of the Rev A to B mods a number of years ago, so this looks like the only thing left to check on the control board before proceeding.

Tnx de John, WB4GLJ

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Reply | Threaded
Open this post in threaded view
|

Re: K2 - Question on control board

Don Wilhelm-4
  John,

R7 is needed for the base K2 current sense.  You should have changed it
to 1.78 k when you did the A to B upgrade.  OTOH, C44 is not used, if
you have any capacitor (to ground) installed that connects to the
emitter of Q11 and one end of R7, remove it, but leave the resistor in.

73,
Don W3FPR

On 12/30/2010 8:13 PM, John Wingard wrote:
> I'm in the process of upgrading my K2/10 (SN 1057) to a K2/100. I am also finishing up the KAT100 tuner and have a question. The tuner instructions state to remove C44 from the K2 control board. I have a Revision A control board without a C44. It also states that if this is the case, a capacitor may have been soldered directly across R7. On my board, a resistor is installed at R7 (no capacitor). Do I leave R7 in or take it out? Incidentally, I did all of the Rev A to B mods a number of years ago, so this looks like the only thing left to check on the control board before proceeding.
>
> Tnx de John, WB4GLJ
>
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html