http://www.discovercircuits.com/PDF-FILES/40kvcr.pdf
wide-output-current range sources that accommodate a wide supply and temperature range, based on LM317
http://www.edn.com/archives/1995/062295/13di3.htm
run 40W fluorescent tubes from any 12V source capable of delivering 3A
http://www.aaroncake.net/circuits/40wflamp.htm
http://www.mrs.bt.co.uk/dubus/8403-1.pdf
receiver circuit for 433.92 MHz data transmissions, uses ASK modulation, based on T7544 IC
http://www.spelektroniikka.fi/rfirkytkis.htm#ask
use a TV-tuner, a simple radio-circuit and a interface to a computer that controls the receiving frequency from 45-860MHz.
http://hem.passagen.se/communication/uv916rec.html
This is a simple short circuit protected 48 V regulated linear power supply design that will provide up to 60 mA of current. Based on the Texas Instruments TL783C high voltage adjustable linear regulator IC.
http://members.aol.com/ecc81/ps48.html
Stack two T-80-2 powdered iron toroid cores together. Use super glue, or some other means to hold the two cores together.
http://www.hard-core-dx.com/nordicdx/antenna/feed/4_1balun.html
Using a 1/2 Lambda coax balun. Includes an online calculator.
http://n-lemma.com/calcs/dipole/balun.htm
This is a rather unusual QRP Power Amplifier design, with a wide frequency response; within three dB's from 300KHz to 30MHz. Overall gain is in the region of 16dB
http://web.telia.com/~u85920178/tx/linear.htm