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Simon_V · 2nd May 2018, 10:57 pm

Pretty much got it sorted out.

output is now a reasonably stable 25 watts.

I must say thank you to GW0PLP Don for letting me pester him to death giving me signal reports.

So here is what I replaced after I reached the 15 watts output. I could make it drop off to around 5 watts by warming the area around the input to the RF board.

C20 & C21 - 33pF
C23 & C24 - 10pF
C25 & C26 - 0.001uf
C27 & C28 - 12pF

Also

R18 & R19 - 10R One measured 11R and the other anything between 10.3R and 10.9R depending if it was warm or cold. Cooling these with freezer spray made the output swing wildly from anywhere from a few watts to nearly full power.

I also went along the entire driver strip peeking the coils L14,L15,L16 & L17 and trimmer capacitors TC1 & TC2. The 4 coils interact with each other so you may have to go through trimming them a few times.

Simon - GW6TKK

2nd May 2018, 10:57 pm	#4
Simon_V Retired Dormant Member Join Date: Feb 2014 Location: Pembrokeshire, UK. Posts: 52	Re: Trio TS711 low or no RF power output Pretty much got it sorted out. output is now a reasonably stable 25 watts. I must say thank you to GW0PLP Don for letting me pester him to death giving me signal reports. So here is what I replaced after I reached the 15 watts output. I could make it drop off to around 5 watts by warming the area around the input to the RF board. C20 & C21 - 33pF C23 & C24 - 10pF C25 & C26 - 0.001uf C27 & C28 - 12pF Also R18 & R19 - 10R One measured 11R and the other anything between 10.3R and 10.9R depending if it was warm or cold. Cooling these with freezer spray made the output swing wildly from anywhere from a few watts to nearly full power. I also went along the entire driver strip peeking the coils L14,L15,L16 & L17 and trimmer capacitors TC1 & TC2. The 4 coils interact with each other so you may have to go through trimming them a few times. Simon - GW6TKK Attached Thumbnails