Posted by
John Huffman-2 on
Nov 18, 2006; 4:41pm
URL: http://elecraft.85.s1.nabble.com/KPA100-Upgrade-and-KAT100-Problem-tp440984p440989.html
Don -
Thanks for the guidance.
> Check all your connecting cables first thing (do a continuity test on both
> the center conductor and shield and check for shorts).
OK
> If you have an antenna analyzer, check each cable with it while connected at
> the far end to a dummy load.
OK
> After checking the cables, if you still have problems, try re-calibrating
> the wattmeter in the KAT100.
Did that and the setting, especially forward was off by quite a bit.
> Pins 6 and 7 of U3 must go to a low level (to scale the wattmeter readings)
> when high power is active.
The Logic selection on my DMM shows LO between ground and pins 6 and 7
of U3 at all times, both high and low power.
Tried again and the KAT100 works a bit better, but the higher the power,
more LEDs light. On 80m at 20W the K2 shows 1.1:1 SWR, but the KAT100
LEDs show 1.3:1. Transmit at full power and all LEDs light and the K2
locks in transmit mode requiring tapping the key several times to get
back to receive.
On 80m at 2w with KAT100 set to AUTO, all is well. With KAT100 set to
CAL, all LEDs light when the key is tapped.
I will do some soldering remelts. Have had problems in the past with
Q3, which was replaced.
Do these symptoms lead to other conclusions?
As always, many thanks, Don.
73 de K1ESE
John
Check to be certain that is happening and that
> the low level scaling signals are getting to pins 2 and 4 of RP1.
>
> 73,
> Don W3FPR
>
>> -----Original Message-----
>>
>>
>> I had been having problems with my KAT100 and hoped the KPA100 upgrade
>> would help. I installed the upgrade and all works well with an external
>> tuner other than the KAT100. But, the KAT100 problems persist.
>>
>> Here's the problem. The KAT100 tunes fine on all bands into my 50 ohm
>> dummy load if I set the power to 10 watts. But, if I set it to 11
>> watts, engaging the KPA100 build into my K2, the bands 160m through 40m
>> won't tune correctly.
>>
>>
>
>
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