Here are pictures of my NN1G Mark I 20m QRP transceiver.
It is VFO controlled, with full QSK, and power output is
about 1.5 Watts. The receiver is a single-conversion
superhet with a 4-pole crystal filter in the i-f. The
radio runs on 13.8 VDC. The rig was built from a semi-kit,
and was designed by Dave Benson, NN1G. I've added a Curtis
8044B keyer, an audio filter (which is a clone of the optional
filter that MFJ sold for their 90xx-series QRP rigs), and a
relative power output meter. The tiny meter and the circuit
behind it were stolen from a junked HyGain CB radio. The
VFO dial uses a small Jackson Brothers vernier for smooth
tuning. The dial is home-made.
Yes, the enclosure is a metal file card box, designed to hold 3" x 5" recipe cards! The front panel is aluminum, marked with rub-on transfer letters, and covered with clear self-stick Mylar film.
This rig is pretty much a complete station in a box. Just add DC power, antenna, key and/or paddles, and earphones, and you're on the air in QRP style!
You may have seen this one before. Pictures of it appeared in the July, 1994, issue of QRP-ARCI's "QRP Quarterly" magazine.