How to make foxhole radio receiver (with no batteries)

Foxhole radio receiver or Crystal receiver is a form of radio that does not operate on local oscillator, which makes it hard to be detected by other electronic device. One of the most interesting thing of Foxhole radio is that it could be operated without the use of batteries, as it is powered solely by the radio waves through its long wire antenna.

Foxhole radio was (supposedly) popular during World War II because it enabled the GI to receive radio broadcast in the middle of the war, particularly in France as the Germans has outlawed the use of radio by civilians, thus the American GI need to build their own receiver to receive broadcasts. Typical component of foxhole radio during those days are : a period razor blade (not the newer galvanized one), carbon (obtained from pencil) and some copper wire with woodblock or cardboard as its base.

I’ve found a video on Youtube on how to build a Foxhole receiver, it still requires considerable skills and experience to build a working version of the receiver though.

Easy to use 555 Timer Electronic IC Simulator Software

The (*)555 Timer IC software has been use in countless of electronic project that requires the use of square wave (Astable). NE555 IC can act as a timer, delayed switch (Monostable), Schmitt trigger and simple memory switch. Here a a selection of Youtube videos that demonstrate the usefulness of 555 IC timer for electronic hobbyist.

IC NE555 TImer

The 555 Timer can help any electronic hobbyist and newcomer to build circuits with Astable or Monostable configuration. The application is very easy to use as the user only need to key in their desirable value of when the 555 timer should activates or deactivates; and the software does the calculation for the capacitors and resistors value.

timer 555

The software is written by Andrew Clarkson, and you can download the software from

Hunting and Scraping for Solar Panels

Late this few weeks I’ve been hunting and finding Solar Panels which can be use to power up various items. Among the Solar Panel that I’ve found is listed below.

solar panels collections

1. 14 volt panel – obtained from a hobby shop
2. 4.5 volt panel – scrapped from a damaged garden light
3. 2 volt panel – scrapped from some car accessories

Why would I need solar panel for?
Just to satisfy my hobby in electronics. The place where i’m staying (Alor Setar, Malaysia) always receives equal amount of sunshine, (near the equator), except for monsoon season of course. So I’m thinking that, it’s kinda shame if I let it waste.

Among of my plans would involve of hooking up one of these panels with a regular car battery and inverter to power up my backyard lamp and various electronic projects that depends on solar power. I’m looking for any good schematic to aiding me, not too complex, but good enough for a beginner.

I would appreciate any of your suggestions, btw.