[Elecraft] K2 - Problem With KAT2 Installation

[Peter Barville]

Hello Don

Firstly, my apologies as I am currently experiencing a few mail 
problems, and this note won't 'flow' as part of the original message thread.

I am very grateful to you Don for your reply. Over the years I can't 
imagine just how many you have patiently helped.

I obviously didn't explain the problem very clearly, but will try and 
clarify things.

J8 is oriented correctly, with the green wire towards the top. I have 
checked the other end of the cable and confirmed there are no shorts, or 
open circuits.

As you suggest, P4 pin 4 has been removed as part of the KPA100 
installation, but I'm not sure what you mean by "Since you have already 
removed P4 pin 4 for the KPA100 you will have U8 also keyed."

No doubt I'm being a little slow, but perhaps you would put me straight?

To clarify the symptoms (I hope):

With KAT2 *not* connected, the rig will power up and perform normally.

With KAT2 *connected*, when I power-up the rig, the S meter goes full 
deflection, and there is no audio output. However, the rig does allow me 
to navigate to, and through, the KAT2 options.

Since my first post, I have removed KAT2 and re-seated U1 in case the 
passing years had resulted in a poor connection between chip and socket. 
As part of that work, the pin mating between the L-C board and control 
board has, by default, been re-seated. No improvement resulted.

73 Peter G3XJS (In hope!)



Don Wilhelm wrote:

 >Peter,

 >Is the green wire in J8 positioned toward the top?  If not, things will
 >not work well.
 >If U8 is oriented correctly, check the other end of the cable for broken
 >wires and shorts.

 >Even so, I am a bit confused, you say you cannot power up the K2
 >correctly, but you can access the ATU menu.  Please elaborate, because
 >on the surface, those two statements seem contradictory, the ATU menu
 >will only display -- if the KAT2 is not connected.

 >You could avoid plugging U8 incorrectly by using the same technique as
 >the KPA100 ribbon cable - just stuff something in U8 at the pin 4
 >location (toothpick, wire, anything that works, you might even glue it
 >in).  Since you have already removed P4 pin 4 for the KPA100 you will
 >have U8 also keyed.

 >73,
 >Don W3FPR

 >Peter Barville wrote:
 > Folks
 >
 > I'm hoping somebody might be able to point me in the right direction, so
 > thank you in advance for reading this.
 >
 > My K2 is serial number 573, so you can see that that I built it many
 > years ago. Similarly, I built and incorporated the KAT2 Antenna Tuner
 > almost as many years ago. However, the KAT2 has not been used for a long
 > time, as I later moved on to installing the 100W PA lid.
 >
 > Although the KAT 2 was working fine when I last had it in the K2 (must
 > be a good few year ago), when I came to replace the 100W lid with the
 > KAT2 (and battery) lid yesterday I discovered there is now a problem
 > with the KAT2.
 >
 > With J8 securely and correctly mated with P4 on the K2 Control Board,
 > the rig will not power up properly. After an extremely brief burst of
 > (probably normal) sound from the speaker, the S Meter goes to full
 > deflection, and the rig goes silent. It is as if the rig is in Tx mode,
 > although there is no RF output.
 >
 > I can access the KAT2 related items in the menu but, unless KAT2's J8
 > is disconnected from P4, the rig will not power up correctly.
 >
 > I am not aware of any mishap having occurred to KAT2 whilst it resided
 > mounted in its lid, but stored away in a box, but wonder whether anybody
 > has any suggestions as to where first to look?
 >
 > Many thanks.
 >
 > 73 Peter G3XJS
 >