Re: RF Power #chat


Alan G4ZFQ
 

Hazarda

*In simple terms*, how can a > novice builder set up his U3S that uses several LPFs in order to avoid > taking such an RF power beating going up the frequencies?   I have 40m, > 30m, 20m and 17m LPFs for my two U3Ss.  Using my 40m WSPR spots as a > baseline, the number of spots on the higher frequencies describe a very > precipitous downward curve.
Without actual power figures it is difficult to tell.
What you see could be normal.
What has been described causes one band to be low out of sequence.
I suspect this is a very unusual occurrence.
You need to measure the RF output.

Judging by WSPR spots may be misleading, have you compared with someone near you with a similar setup?

73 Alan G4ZFQ

I know there are (or could be) several explanations for this, but somewhat primitively monitoring U3S signal strength with my receiver's S-meter indicates a successive power drop going up these frequencies, which I understand is more or less to be expected, but is still something I'd like to minimize to the the extent good construction and setup can.  As it stands, these higher frequencies are scarcely worth powering up.

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