Here is the simple solar battery charger circuit designed to charge a 5 - 14v battery using LM317 voltage regulator. It is very simple and inexpensive.
Ham Radio for Arduino and Picaxe by Arrl
Build your own variable capacitors.
4:1 BALUN : RogerTango.com
HB1B Four Band CW QRP Transceiver - 80-40-30-20 Meters
this is something I want to build and try to add a IC chip circuit to it and see how many stations it will receive.
KK5JY Serial/USB SWR Meter for Arduino
Mini-Whip active antenna 10khz - 30Mhz by Roberto Chirio
Homemade Magnetic Loop antenna for 27 MHz
60 years ago, this is what homebrew ham radio looked like. Puts me in a building mood.
End Fed Antenna
Panadapter Yaesu FT817 897 857 rtl2832 e4000 dongle i6ibe
Magnadyne Radio Balilla 1937-39 Italy with <3 from JDzigner www.jdzigner.com