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Mine outputs 1.5kW.

OK, it's 1.5kW divided by a bunch.? On every TT2 I've built, It's been ~250mW or so. Maybe as much as 350mW.? My measuring method isn't too exact.? I've used both my homebrew analog dummy load wattmeter (modified slightly from EMRFD) and the Elecraft dummy load with a peak detector circuit built in it.?

It seems to me I may have also used a similar homebrew QRP dummy load/detector in an empty water chestnut or chicken chunk can I nicked from the trash bin when Mom was busy playing the NYT Spelling Bee on her phone or something. The best thing about building this stuff having to eat delicious foods "for science." I'm always dragging home something "for the can."? Not the first person to do it, I built one solid-state transmitter in a canned Ham can on a wooden base. It has a fixed-in-place crystal because it required tuning a trimmer cap. Next one will likely have a crystal socket (maybe an octal socket?) of some kind and a broadband circuit.? Nor' Easter Ham. That would be a cool Rex product, but I think the name is already taken...

As for a practical matter, measuring power in this situation really doesn't matter too much-- ball park is probably good enough to know it's working right. You'll have all kinds of losses that could change a little from day to day during operating sessions (including propagation). There will also be differences from unit to unit.? I think the litmus test is really the RBN or on air results, remembering that if you are pretty sure you've got 1/4W or a? little more leaving the rig and propagation is good, you might be heard a surprisingly long way from home.? I called CQ on 40m last night with one of the $3 eBay Pixie kits and the RBN found me 1100 miles away. I have an inverted Vee at 18ft.

My semi-educated thought on the matter is this: If you have a way to peak an output (e.g., expanding/contracting coil windings, swapping out lower-output transistors), that's a good and right thing to do. Every little bit counts at QRPp levels. BUT... the better thing is to trade a little power for a good sounding signal, if the situation arises.? Still, I wholehearted applaud your pursuit of an academic exercise. Bonus points for you! That's how I got started on the path to a career as an EE.

A final thought-- EVERYONE that likes to homebrew should build at least one TT2. It's a rite of passage for those of us that missed it the first time around (I was 5 in 1978) or at least it's something good and holy. It's funny that such an idea has influenced so many people enough to become an indisputable icon. :)

Rex-- Shoot me an email off list. I may have some information of interest to you.

-HRS