[Elecraft] K2-KAT2

[Don Wilhelm]

Hans,

If you are getting HiCur messages, you may not have a proper connection 
through the KAT2 to the dummy load.

Be certain the crimp pins of J7 are inserted correctly.  Looking at the 
rectangular holes in J7, you should see the crimp pins flat against the 
inside of the housing (no space), and the latching tabs on the crimp 
pins should be visible if you push on the wires.  If the crimp pins are 
inserted correctly, you should be able to move the crimp pins slightly 
and see the ends of the latching tabs.  If there is not a small bit of 
movement, the pins are not inserted correctly.

The shield side of J7 must be closer to the K2 right side panel than the 
center conductor.

The 000 indication may be due to no power through the wattmeter (T1 and 
associated components) of the KAT2 (that will also cause HiCur messages 
from the K2), and that condition could be due to either incorrect 
connections at J7 or improper winding and connection of T1.  Note, the 
C55 null adjustment requires that power is flowing through the wattmeter.

Check T1 against the diagram in the manual - it must be *exactly* as 
indicated.  Make certain it is not wound in reverse from the diagram and 
that the leads are in the correct solder pads.  The 1 turn winding 
(green wire) must also be correctly in place.
Incorrect winding of T1 is the most common builder error for the KAT2.

Try inserting wires into the J7 housing to make contact with the crimp 
pins and measure the resistance with your DMM.  The resistance should be 
the same as your dummy load.

73,
Don W3FPR

On 3/13/2013 10:23 AM, Hans Elfelt Bonnesen wrote:
> K2 - KAT2-
>
> Every reading and function seems to be ok UNTIL page 17 – square five in
>
> Bridge Null Adjustment (C55):
>
> After placing the K2 in CALn  and exiting that setting by pressing MENU twice,
>
> I’m ready to put the K2 in TUNE mode:
>
> With the R1 and R2 set fully clockwise, and C55 positioned parallel
>
> to the rear panel edge and pressing TUNE I get:
>
> ”000 followed briefly by HI-cur + atu. Thereafter HI + atu disappears and 000 stays on.
>
> The adjustment of C55 does not affect the display at all.”
>
> +++
>
> A further DMM-check of voltage on pin1 of U4 gives 0,00 volts, and still reads 0,00 volts in tune mode.
>
> (not the reading in the range of  3 to 4 volts, as advised )
>
>