Proximity Sensor (drive a relay)

[victor nery]

Greetings,

I would like to know how it's possible to adapt some circuit to get true bypass relay swithcing using the JRC-19F (4078). My ideia is to use a sensor of proximity to drive the relay acting as an spst (on/off switch) but as I'm just a nobbie in electronics I don't know how to accomplish this objective. I intend to use this switching in a wah pedal like the CB instead of the foot switch.

The first idea I thought of was to use a circuit with the 4093N as we find in some boutique pedals and just connect the emiter of the second transistor (NPN) to the relay. Would it be enough to drive it?

The second point is if I can use the wah enclosure to detect the proximity of the foot and get the sensor working properly.

Thanks in advance 

[crane]

First two things that come into my mind are reed switch or LDR + LED.
Hysteresis should be built in for stability.