CIRCUITS
POWERFULL FM TRANSMITTER. 100 MHz : 2 WATTS : 15 KM RANGE
FM BOOSTER - Listen to programmes from distant FM stations clearly.
FM Dipole for 88-108 MHz - A simple dipole antenna can be used for improved reception of FM broadcast signals.
COLOUR SENSOR - The circuit can sense eight colours, i.e. blue, green and red (primary colours); magenta, yellow and cyan (secondary colours); and black and white.
AUTOMATIC ROOM POWER CONTROL - The circuit uses two LDRs which are placed one after another (separated by a distance of say half a metre) so that they may separately sense a person going into the room or coming out of the room.
Parallel Port Relay Interface - Here is an example of controlling a relay from the PC's parallel printer port (LPT1 or LPT2)