SPDT switch with phototransistors

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The discussion focuses on creating a single pole-double throw (SPDT) switch using phototransistors activated by IR LEDs, emphasizing simplicity and minimal components for experimental purposes. The user specifies a preference for electronic switching rather than mechanical, indicating a desire to utilize phototransistors effectively. There is interest in exploring whether a single phototransistor can operate the SPDT or if multiple units are necessary. The conversation also touches on the potential use of a photo-darlington type transistor for this application. Overall, the goal is to develop a straightforward circuit design for the SPDT switch.
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Hi all. I am looking on how to make a single pole-double throw (SPDT) switch using phototransistors that can be activated by IR LEDs (not from a remote, i.e. in pulses, but as a single arrangement of a switch, cell, and IR LED).

Please keep it simple, I am only doing experiments. I don't require any complicated circuits, but just using the minimal of components.
 
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univeruser said:
Hi all. I am looking on how to make a single pole-double throw (SPDT) switch using phototransistors that can be activated by IR LEDs (not from a remote, i.e. in pulses, but as a single arrangement of a switch, cell, and IR LED).

Please keep it simple, I am only doing experiments. I don't require any complicated circuits, but just using the minimal of components.

Do you want the switch contacts to be mechanical (like with a relay), or electronic (like with analog switch ICs)? What voltages and currents will the switch contacts see? You will need two receive pickups, right? To actuate the two "positions" of the pole?
 
I'm using phototransistors, so of course, an electronic one. I'd also like someone to try and make a SPDT that uses one phototransistor, if not, then two or even more. Since I find difficulty in finding phototransistors, it should be the reason why I would like to hear about a single phototransistor-operated SPDT.

I think, could a photo-darlington type transistor with three legs be used for this purpose?

Please don't take it as a very demanding post.
 
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