wiring a push pull as an on off switch

axisus

I want to switch an LED on using a push pull pot. Anyone know how I would wire that up? Presumably the live wire from the battery goes in somewhere and comes out somewhere?

Danny1969

You can put the switch in between the positive and the LED or the negative and the LED, I prob would put it in the positive though
Bear in mind if the LED doesn't have it's own current limiting resistor inside then you need to add one in series with the  battery otherwise the LED will destroy it's self 

axisus

Danny1969 said:

You can put the switch in between the positive and the LED or the negative and the LED, I prob would put it in the positive though
Bear in mind if the LED doesn't have it's own current limiting resistor inside then you need to add one in series with the  battery otherwise the LED will destroy it's self 

Yeah, resistor sorted, I just need to know where to put the wires on the switch!

Danny1969

Assuming a typical DPDT push pull switch then one wire on one side centre contact and one on same side end contact .... which end depends on whether you want it on when switch down or up 

axisus

Danny1969 said:

Assuming a typical DPDT push pull switch then one wire on one side centre contact and one on same side end contact .... which end depends on whether you want it on when switch down or up 

Ta! Any earth wire as well?

Bridgehouse

axisus said:

Danny1969 said:

Assuming a typical DPDT push pull switch then one wire on one side centre contact and one on same side end contact .... which end depends on whether you want it on when switch down or up 

Ta! Any earth wire as well?

Just been musing. If it's proper "off" rather than just "sort of off" then do you actually need to ground "off off" at all?

Danny1969

No, we tend to ground signals when switching them off as leaving them "floating" tends to create noise and in some cases parasite oscillation ......... an LED or lamp or anything else just needs to be open circuit to be off  ......... if you attempted to ground the DC volts feeding it you would actually just short circuit the battery so not a good idea

axisus

Danny1969 said:

No, we tend to ground signals when switching them off as leaving them "floating" tends to create noise and in some cases parasite oscillation ......... an LED or lamp or anything else just needs to be open circuit to be off  ......... if you attempted to ground the DC volts feeding it you would actually just short circuit the battery so not a good idea

Thanks!