Re: Thoughts on Low Power and fewer turns on LP filter toroids


Michael.2E0IHW
 

Apart from soldering issues, this must be  the most confounding disincentive  for faint-hearted wonnabe QSX+ers ...

There must surely be a concise winding-checklist for genuine radio "amateurs" ?

Michael 2E0IHW
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On 08/09/2020 17:57, Phil/K3UT (ex W3HZZ) wrote:

I've completed a 20M QCX+ and have just fixed a friend's 30M QCX+. Both are working nicely, but at 13.1 volts I get about 3watts output on both, using the onboard RF tool to measure (and less on my Elecraft wattmeter). 

To achieve that output, I had to take two turns off L1 and L3 and one turn off of L2 and fiddle around a little with the spacing of the windings. I did that with both radios.

Any thoughts why the number of turns differs so greatly from that specified in the build instructions? Both kits were shipped about the same time. Could it be a quality control issue of the toroids? I measured the toroids on the 20M version before I installed them, and they were spot on before I took the turns off. I didn't measure them after the turns had been removed.

I'm satisfied with the power output of the units.  Just curious why they aren't meeting the specs as stated in the manual?

Phil, K3UT

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