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This circuit can be used with a timer clock to open and close curtains or (vertical) Venetian blinds. The curtain or blind is driven by  an electric motor with a reduction gearbox fitted to the control mechanism of the curtain or blind. This circuit is ideal for giving your home an occupied appearance while you are away on holiday or for some other reason. In the author’s house, this arrangement has provided several years of trouble-free service on a number of windows fitted  with Venetian blinds. The original design was a simple relay circuit with pushbuttons for opening and closing and reed switches acting as limit switches. The mechanical drive is provided by a small DC motor with a reduction gearbox and pulley (all from Conrad Electronics).  It was later modified to work automatically with a timer clock. The timer operates a small  230-VAC (or 120-VAC) relay with a changeover contact. Thanks to the two timers, the motor stops after a few seconds if one of the reed switches is miss...

The door opener derives its power from a 9-V battery. A momentary-contact switch, 52, is provided in the event that manual opening and closing is required. Relay Kl is a 9-V type and relay K2 is a 117`Vac latching-type, which automatically latches with the first burst of current and opens on the second burst. Door Opener Alarm Circuit Diagram The gate lead of the LASCR is not used; a light source triggers the LASCR unit into conduction, causing current to flow in the coil of the relay. That, in turn, causes Kl`s contacts to close, thereby energizing K2 (closing its contacts), and operating the garage door motor.

This circuit can be used with a timer clock to open and close curtains or (vertical) Venetian blinds. The curtain or blind is driven by  an electric motor with a reduction gearbox fitted to the control mechanism of the curtain or blind. This circuit is ideal for giving your home an occupied appearance while you are away on holiday or for some other reason. In the author’s house, this arrangement has provided several years of trouble-free service on a number of windows fitted  with Venetian blinds.  The original design was a simple relay circuit with pushbuttons for opening and closing and reed switches acting as limit switches. The mechanical drive is provided by a small DC motor with a reduction gearbox and pulley (all from Conrad Electronics).  It was later modified to work automatically with a timer clock. The timer operates a small  230-VAC (or 120-VAC) relay with a changeover contact. Thanks to the two timers, the motor stops after a few seconds if one of t...