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QMX+ Low Power and higher SWR seep values on higher bands


 

开云体育

Hello

I am trying to decide a route to improve RF power on 20m band (now with 2,5w). 17 and 12 also very low at about 1,7w.

I noticed high SWR near 2.0 in the higher bands 20m up in the diagnostics, when connected to a dummy load.

Is this normal?

RF filter sweep looks decent on 20m, but this is my LPF sweep on 20m:

?

Should I try to lower LPF filter curve??

This is achieved adding inductance value to one of the L515 or L516?

It will lower power on 15m as the LPF is shared?

Your help please.

Thank you

Luis

CU2IJ

-- 
Cordiais saudacoes,

Luis Antonio Mota Albergaria Pacheco
luis.a.albergaria@...
luis.a.albergaria@...
(+351) 962374276


 

The dip in your passband of the LPF is unfortunate, and you may try to move the windings a bit to see if you can reduce it.
But don't try to move the cut-off frequency down, since it is set to cut off just above 15M, which shares this filter.