[Elecraft] KAT100 Power Calibration Problem

[Don Wilhelm]

Jeremy,

How much power are you sending through that wattmeter?  If it is 20 
watts or more, it may just be that 30 mV is OK.

73,
Don W3FPR

On 2/28/2014 9:55 PM, JeremyJones wrote:
> I've taken the watt meter out of the loop, and have the K2 set for 10W.
> Double checked the windings and solder on T1, and it still won't go below
> 30mV.  I definitely have C31 at the low spot as the voltage climbs on either
> side.  I still can't get anywhere the voltage needed at U5 pin 5 for the
> power calibration.
>
> Jeremy
> VA3ZTF
>
>
> Don Wilhelm-4 wrote
>> Jeremy,
>>
>> Tune the capacitor very slowly and use a non-metallic tool.  The null is
>> sharp and deep.
>> You must have a good 50 ohm dummy load connected.
>> You may want to take your external wattmeter out of line to do the
>> nulling.
>> The actual voltage will depend on the power level, at 5 watts it should
>> be less than 10 mV, but you should be able to get it below 15 or 20 mV
>> if the power is 10 watts.  If you are using 20 watts or more from the
>> KPA100, then your 30 mV is probably OK.
>>
>> Ideally, the voltage should go to zero, but being practical, one may not
>> be able to adjust the capacitor in fine enough increments to achieve
>> that goal.
>>
>> 73,
>> Don W3FPR
>>
>> On 2/28/2014 4:32 PM, JeremyJones wrote:
>>> I just reread Dons post, and he says less than 10mV, so I guess I have
>>> some
>>> trouble shooting to do with that first,
>>>
>>> Jeremy
>>> VA3ZTF
>>>
>>>
>>>
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