Problem solved. Rookie error. Could not figure out how changing R5 made absolutely no difference. Well, turns out that you really need to have R6 in the circuit. Marty

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Hi group happy holidays to all my name is Terry and I have a question built a 10-watt pa from QRP labs and when adjusting the r215 variable resistor the amp fluctuates. Now at startup, the amperage re

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I couldn't agree more. Plus an added bonus of having a community of people who have built the same kit, that can help point you in the right direction is valuable. This is especially true for someone

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All, I sincerely hope that it wasn't taken as criticism. Admittedly it was my own misunderstanding. This kit was a joy to build, and I'm excited to integrate it into my own design. After building a QC

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Hello Halden This often happens when using the unit on VHF where the BS170 has to work a lot harder - you need higher idle current to get good power output. Yes correct I believe that would work fine.

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I would say no. In that configuration I think it's better to run only 1 BS170 at 5V. Generally that will give you 200 mW out of the U3S on 40m and probably 30m as well. --Al WD4AH

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Hello Daniel. You sort of can using what I call the "burnt finger tip method". The clues in the name. To get a ball park figure, I use my index finger to monitor the temp of the BS170.. Adjusting the

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