[Elecraft] K3 with 2m tvtr - power control feature request

[Dave Sublette]

One more reason I forgot to mention.  If your power output has to be adjusted every time you switch to the band using the transverter, sooner or later, you will forget.  That might be the end of your transverter.  That is why I always set my stuff up so I don’t have to make any adjustments when bandswitching.  We are all prone to making mistakes. I try to prevent myself from making damage this way whenever possible.

73,

Dave, K4TO
> On Jul 6, 2017, at 10:49 AM, Don Wilhelm <donwilh at embarqmail.com> wrote:
> 
> Graham,
> 
> You say you have measured the input power to the K144XV and it is a max of 0dBm and a minimum of -7dBm.  If that is incorrect, then my conclusion (following) is wrong.
> 
> A difference of 7dB should produce 1/20 of the power developed at 0dBm - based on 10 watts output, you should obtain 0.5 watts output with the -7dBm input.
> 
> So my conclusion is that the K3 is "doing the right thing", but your K144XV is not.  Perhaps there is some sort of oscillation in the K144XV that is causing your problem.
> 
> We obviously don't have all the answers here, so I recommend you contact K3support because they have access to the designers and production test folks to seek out an answer for you.
> 
> Do you have any way of determining the output frequency on 2 meters? That may be helpful information for support.
> 
> 73,
> Don W3FPR
> 
> On 7/6/2017 10:13 AM, Graham Kimbell wrote:
>>    * the max output is supposed to be 10W, but measures 7W even after
>>      calibration - seems wrong but I can cope with this
>>    * the minimum power is 5W but should be down 10dB on the max, ie
>>      0.7W.  This is a problem because I need about 1W to drive the
>>      microwave tvtr.
>>    * the XV config that allows setting the 28MHz input to the tvtr has
>>      been checked and is exactly the 1mW (0dBm) default.  With the
>>      power control set to minimum it measured -7dBm.
>> So it appears that the internal 2m xvtr has too much gain, and there does not appear to be any way to reduce the power output below 5W.  Is there any chance of making this possible?
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