[Elecraft] New Output Power Issue

[Lyle Johnson]

Using a DVM or other self-contained voltmeter, measure the voltage at 
the power supply end of the cable during Rx and Tx.  Is the voltage drop 
small (under 1/2 volt)?

Measure the voltage at the radio end of the cable (using the same 
voltmeter) during Tx and Rx.  Compare it to the K3 voltmeter.  The 
difference between the two voltages should be almost constant, with 
perhaps a couple tenths of a volt greater difference when in Tx. Is the 
excessive voltage drop occuring across the cable? Might it be poorly or 
improperly mated Anderson power-pole connections?  Or loose connections 
at the power supply?  Are you using a power distribution box like a 
RigRunner?  Is the drop occuring there?

The most common cause of this sort of problem is the cabling -- 
including connectors -- between the power supply and the radio.

73,

Lyle KK7P

> Update on my low output issue:
>
> I ran the TX Gain Calibration this morning, and everything passed with 
> flying colors.
>
> I am seeing about a 4-4.5V drop across the radio when going from rx to 
> tx.  Rx voltage sits at 13.8V, but when I transmit, voltage across the 
> rig drops to between 9 and 9.5V.
>
> All tests performed while tuned into a 300W dummy load.
>
> Before I tear into my rig and start looking for corroded tin pins on 
> the PA board (K3 #281, so unlikely the board was replaced/mod 
> performed), is there anything else I should test while my station is 
> still all together in one piece?
>
> Thanks to everyone for the assistance, and Merry Christmas!
>
> 73,
>
> --Ian
>
> Ian Kahn, KM4IK
> Roswell, GA  EM74ua
> km4ik.ian at gmail.com
> K3 #281, P3 #688
> HRD v5.x/6.0 Test Team
>
> On 12/23/2012 5:07 PM, Don Wilhelm wrote:
>> Chuck,
>>
>> It could - defer decisions on that until after doing the TX Gain 
>> Calibration.
>>
>> 73,
>> Don W3FPR
>>
>> On 12/23/2012 5:01 PM, hawley, charles j jr wrote:
>>> Could it be/affect a 40% difference?
>>>
>>> Chuck, KE9UW
>>> Lionel Trains, TCA, LCCA, LRRC
>>> aka Jack, BMW Motorcycles BMWMOA #224
>>>
>>
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