Re: low output only on 40m

M0OOZ
 

Note: I have, like others, injected RF and manually swept the frequency through from 1 to 30 MHz. There is a horrible dip at the lower end i.e. 40 MHz is really low compared to 20 MHz. Yes I realize that this uses different filters. I even made a 'software tool' from modded code. 

The software tool allows me to 'manually' (via arduino serial monitor), change the filter switching, so I can see exactly what is switched in and out, while testing. I did this because at one point I noticed RF appearing on two filters at the same time, which did not seem good, and would have accounted for the apparent attenuation @ 40 Meters. (two filters being connected together would necessarily present a different load and produce characteristics that are non desirable.)

 

I love the idea of the uBITX, but it has actually really dun my head in!

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