Video Switcher

Video Switcher - Automatically or manually switch the outputs from up to four cameras into one video monitor. 8 pages. Not available as a kit of parts.

Remote two wire positioner

Remote two wire positioner - Send power to a remote stepper motor and also control its rotation and speed over only two wires. Not available as a kit of parts.

Direction sensing motion detector

Direction sensing motion detector
Detects motion and indicates the direction that a human or animal is moving

fm transmitter

fm transmitter schematic, PC board pattern, and parts placement for a low powered FM transmitter. The range of the transmitter when running at 9V is about 300 feet. Running it from 12V increases the range to about 400 feet. This transmitter should not be used as a room or telephone bug.


parts



Notes

L1 and L2 are 5 turns of 28 AWG enamel coated magnet wire wound with a inside diameter of about 4mm. The inside of a ballpoint pen works well (the plastic tube that holds the ink). Remove the form after winding then install the coil on the circuit board, being careful not to bend it.

C5 is used for tuning. This transmitter operates on the normal broadcast frequencies (88-108MHz).

Q1 and Q2 can also be 2N3904 or something similar.

You can use 1/4 W resistors mounted vertically instead of 1/8 W resistors.

You may want to bypass the battery with a .01uf capacitor.

An antenna may not be required for operation.