Sensor modification see picture

[Goldenshuttle]

This lovely and cheap IR sensor..it works by proximity...when you wave your hand it comes on...time on-off is adjusted by VR1 pot.
Can anyone please suggest how to modify the circuit to make it work like wave with your hand wave-on..then wave-off...??

the IC used is 4093 which is NAND gates

 

[BradtheRad]

wave-on..then wave-off...??

A toggle flip-flop. Also divide-by-2. It probably can be done by revising the connections between NAND gates, although it will require some effort to figure out what is the minimum amount of alteration that will do it.

 

[d123]

Hi,

I'm probably wrong, but at a guess, a method could be removing R5 Vr1 C3 and replacing them with an SR latch. Leaving U1b 5 and 6 tied together.

Again, I may be very wrong...and that's a half-thought out idea. Better to look at these links for on-off momentary pushbutton circuits (pressing a button twice is the same as waving twice):

http://www.mosaic-industries.com/embedded-systems/microcontroller-projects/electronic-circuits/push-button-switch-turn-on/latching-toggle-power-switch.

Searching for "On-off momentary pushbutton schematics/circuits" should provide some useful links and ideas.