RC Switch

It is sometimes necessary for an RC (remote control) model to contain some kind of switching functionality. Some things that come to mind are lights on a model boat, or the folding away of the undercarriage of an aeroplane, etc. A standard solution employs a servo, which then actually operates the switch. Separate modules are also available, which may or may not contain a relay. A device with such functionality is eminently suitable for building yourself.

Resistors:

R1 = 470k

R2 = 150k

R3 = 47k

R4 = 100k

R5 = 4k7

Capacitors:

C1 = 10nF

C2 = 1nF

C3,C4 = 100nF

Semiconductors:

D1 = BAT85 or similar Schottky diode

D2 = 1N4148

IC1 = CMOS 555 (e.g., TLC555 or ICM7555)

IC2 = 4049

IC3 = 4013

T1,T2 = BC547B

Miscellaneous:

JP1 = jumper with 3-way pinheader

K1 = servo cable

K2 = 2-way pinheader or 2 solder pins

PCB, available from The PCBShop