This is a very fine accessory for the QRP operator. It is a Stockton Bridge/Directional Coupler type of instrument. Note the two possible ranges on each meter (Forward and Reverse Power)...you can build it for a range of either 0.2 Watt to 6 Watts or 0.1 Watt to 2 Watts. Actually, with the addition of a DPDT switch and two additional trimmers, you can have both ranges.
I chose to build mine in two Altoids tins glued together, but it will fit in one, meters and all, with care taken to insulate the meter contacts.
Check out the NoGa site under "Kits" for some other builders' photos.
