Very Easy R/C Circuit


The following diagram is a very easy and efficient receiver for actuating garage doors, starter motors, alarms, warning systems and numerous some other possibilities.

Very Easy R/C Circuit

The SCR, that has a extremely low trigger present of 30 uA is common -- it requires an input electric power of just 30 uW to switch on the relay. A high Q tuned antenna circuit assures rejection of spurious signals. A whip or wire antenna is adequate as much as 100 feet from a low power transistor transmitter. A momentary-off switch resets the circuit.

The circuit specifies a whip or wire antenna which just indicates a solid piece of wire 6-12 inches long (15-30cm). The antenna coil is experimental, however you can start with ten to 12 turns of #22 (0.7mm) magnet wire, and 5/16" (8mm) coil diameter. Antenna wire is soldered at 1/2 turn of the coil and the gate of the BRY35 is soldered about halfway the coil. This circuit will transmit as much as 100-feet with the above specs @ 30uA.

The relay coil is specify's as much as 200 ohm but that's just the one I had in stock. Any low-ohm relay, even at 9V or so, ought to accomplish the task. And one remaining note, do not be expecting too a lot from this circuit. The "Very Easy R/C Circuit" is simply that; Easy!

The BRY35 is really an classic semiconductor produced by Philips. A great replacement would be the EC103D1, also produced by Philips (see pin-out picture for this device). NTE Semiconductors gives an alternative of NTE5405, but I have not attempted it. I think, a NTE5400 (30V) or NTE5401 (60V) will function just also. The NTE5405 is a bit overkill at 400V.