Hi-Cur problem

[Ron ZL1TW]

Hi,
      I have been building a K2/100 for a friend, and it has all been going
very smoothly....until tonight.
I had the amp installed and it put out the output it should on all bands,
but I didn't have the power calibration as good as I liked so I took the
amp out, removed the shield and set it up along-side the K2 ready to adjust.
Set to 5w, press tune on 40m and the HI-CUR warning comes up. I then find
it does that on *all* bands EXCEPT 80m.
I take things apart and find it is a problem in the basic K2 ( #4506)
Time for bed here and I am not thinking straight, but that has me bluffed
at present.
I am assuming the problem is most likely in the LPF as the amplifier must
be looking into a short or open cct.
Can anyone come up with a thought or two as to what has gone wrong? The
relays seem to be switching as I change bands.
I have been over both sides of the RF board with a head-band magnifier...it
eludes me at present!
Cheers.......Ron ZL1TW

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[Don Wilhelm-3]

Ron,

If you are certain it was producing near to full output with the KPA100
installed, then I would conclude that something happened when you removed
the KPA100.

I would be looking for something like a short in the coax or its connector
or something equally 'dumb' like that.  OTOH, Hi-CUR usually does indicate a
problem with the LPF, but if it is showing up on all bands except 80
meters --- that would mean that all the other low pass filters suddenly
changed, and that is not probable.
Perhaps a bit of wire came loose as you removed the KPA100 - try a bit of
'upside-down shaking'.

Did your power supply voltage sag somehow?  Do you still have a nice low
resistance at the power connector?  Look for things of that nature before
digging too deep into the K2 itself.

Perhaps it will be more clear after a bit of rest. Good luck!

73,
Don W3FPR

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

> Hi,
>      I have been building a K2/100 for a friend, and it has all been going
> very smoothly....until tonight.
> I had the amp installed and it put out the output it should on all bands,
> but I didn't have the power calibration as good as I liked so I took the
> amp out, removed the shield and set it up along-side the K2 ready to
> adjust.
> Set to 5w, press tune on 40m and the HI-CUR warning comes up. I then find
> it does that on *all* bands EXCEPT 80m.
> I take things apart and find it is a problem in the basic K2 ( #4506)
> Time for bed here and I am not thinking straight, but that has me bluffed
> at present.

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