Schematics / Electronic Projects
Intercom
I built this unit using bits from the "Junk Box", and assumed others might like to do the same. If you don't have......
Light Operated Switch
This unit can control up to 500W of lighting. However the load must be resistive, i.e. normal lamps. Lights containing transformers are not suitable....
Logic ChipTester
The ChipTester presented here is used with an IBM compatible PC, and will test nearly all logic devices, providing they operate from a single 5V supply and have no more than 24 pins....
Loop Alarm
The unit features two separate protection arrangements. The entry/exit is protected using standard normally-open and/or normally-closed sensors such as magnetic switches and pressure mats....
Mains Power Switcher
This Mains Switcher will allow you to turn all the equipment on or off, by operating the switch on just one item. When you turn off the switch on the PC, the monitor, printer and other bits are powered down automatically....
Multicore Cable Tracer
The Sender unit is connected to up to 64 wires at one end, and then the Readout unit is used to indicate which is which from the other end. The Readout is simply connected to any two wires at the other end, and the display indicates which wire number the positive lead is connected to....
PCB Drill Controller
This unit was designed for the Expo Reliant drill. The controller can power other small PCB drills, as well as other devices containing small 12 Volt DC motors, although some changes to component values may be necessary....
Printer Sharer
The Printer Sharer will allow two PC's to share one parallel (Centronics) printer without manual intervention....
Remote Control Extender Mk1
This project allows one to take the video recorder and satellite receiver remote controls upstairs, and operate the equipment from there. There is no additional cabling to install, the signal being carried along the existing coaxial aerial cable linking the two rooms....
Remote Control Extender Mk2
This project allows you to take the video recorder and satellite receiver remote controls upstairs, and operate the equipment from there. There is no additional cabling to install, the signal being carried along the existing coaxial aerial cable linking the two rooms....