Re: The new uBITX boards are here

 

I made the mod to my V3 board to change C81 (near Q90) from 0.1 uF to 470pF,  this was to get more even output power across the bands as suggested by
Farhan. 

After doing this my output dropped to about 500 mW !  I was worried that I might have toasted Q90 (literally) in the process so I went back
to 0.1 uF for C81 and I am now back at the previous power levels, so obviously Q90 is still fine.  

After looking at the schematic again, it occurred to me that I either installed the wrong value cap at C81 or perhaps making this change necessitates
re-adjusting the trimmer pot RV1 ?   Can anyone who has successfully made this mod to their v3 board tell me if this is the case? 

Thanks 

Michael VE3WMB 

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