Solving a Circuit Problem with SPDT Switches

[frenchero]

Hi,

Here is my problem, I am using a circuit with two SPDT switches that I would need to make work in phase.
I would like to activate the two SPDT switches with an another SPDT switch in order to put the two first PDT in one position at the same time (the use of only one external switch is very important). For example when I push the external switch on L1 position the two SPDT in my circuit will go also on L1 position.

I would like to know how to do it in a fancy and compact way and without using and integrated circuit if possible. Is it feasible? Can I buy switch without the big mechanical part as i don't need it for the two I want to use in my circuit?

I hope I was clear I've atached a scheme of my circuit.

Thanks!

 

[vk6kro]

You could use a double pole double throw switch.

http://upload.wikimedia.org/wikipedia/commons/thumb/e/ec/DPDT-symbol.svg/100px-DPDT-symbol.svg.png

This is two SPDT switches controlled by the one mechanical lever.

Or, you can get rotary switches that do the same thing.

 

[frenchero]

thank you! I am not reaaly an expert in electronics!
and do you know a site that references suppliersfor this?

 

[vk6kro]

Depends where you are.

Radio Shack seems to have a good range although you may find them cheaper elsewhere.
http://www.radioshack.com/search/index.jsp?kwCatId=&kw=switch&origkw=switch&sr=1

Just about any big electronics store should carry DPDT switches.
Get one you like the action of, but find out how much current it will need to carry first.

 

[zgozvrm]

You would probably either want to use an SPDT switch (in addition to the DPDT that vk6kro suggested) or get a 3-position (center off) DPDT to use as an OFF switch.

Or, if you're set on using a SPDT switch for control, you could use a DPDT relay to do the switching for you. The switch would energize the relay, the relay would switch the polarity.