Switches, on and off... and stuff. Is there a site where you could learn about different switches (since I'm sort of an engineering/electronics newbie)? I have basic information about reed and mercury switches, but some more complex ones maybe? Please share information about unusual switches.

there's relay switches, which when a certain current passes through them they active an electromagnet closing another switch inside the relay itself thus completing a second circuit.

 

Maplins electronics (UK shop) have a wide variety of different switches

 

then there will be all of the remote control ones; such as infa-red recievers, LDR (light dependant resistor) can be paired up with devices which need a current to be active (such as a transistor) to form a 'switch'... similarly a thermistor (resist which varies with heat).

 

if you think of a design idea im sure one of us could come up with a suitable switch!

Infra-red receiver switches? Like a) activated when infra-red signal received b) something's blocking the light causing them to activate? Reminds me of James Bond or something.

semicondutor optical and magnetic switches maybe of interest also? no moving parts )

 

you may find the Hall Effect interesting

i found this ages ago to explain the hall effect:

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/hall.html

i think its a very good site.

 

infa-red swithces as in complete circuit when there is an IR souce nearby and vice versa.

 

"magnetic switches maybe of interest also? no moving parts )"

 

umm, maybe it was the ) that was meant to make it a joke, but it didnt seem it.. magnetic switches all have moving parts (internally that is) and externally the magnet needs to be moved.

 

last year i made a simple circuit with a reed switch which when a door opened (and the magnet attached to the door pulled away) the alarm went off. (it was a reverse reed switch, so when the magnet went away then the circuit was complete).

I've always liked transparent (glass tube) mercury switches. I should get myself one just so I could watch the mercury sliding in it.

i dunno if its mercury any more... to expensive, they've probably come up with some kinda cheaper compound - i dunno that, just guessing!

"magnetic switches maybe of interest also? no moving parts )"

 

umm' date=' maybe it was the ) that was meant to make it a joke, but it didnt seem it.. magnetic switches all have moving parts (internally that is) and externally the magnet needs to be moved.

[/quote']

no, it WASN`T a joke, maybe you didn`t read the site you quoted as a link, the hall effect semiconductors have no moving parts!

ooops, i was thinking more like reed switch and relays, they have moving parts, but things like transformers + hall effect etc have no moving parts.

"i dunno if its mercury any more... to expensive, they've probably come up with some kinda cheaper compound - i dunno that, just guessing!"

 

Sure, there are tilt switches that don't involve mercury. But I think pure mercury is more reliable, and more dynamic.

"i dunno if its mercury any more... to expensive' date=' they've probably come up with some kinda cheaper compound - i dunno that, just guessing!"

 

Sure, there are tilt switches that don't involve mercury. But I think pure mercury is more reliable, and more dynamic.[/quote']

 

Thats what I thought to but can you name any alloys that are liquid at room temperature that dont contain gallium? Gallium will make it stick to the walls of the device.

ummmmm... nope!!!

 

still, you never know, could be some new compound, but as i said in the first post i was just guessing!

 

Some gallium compounds aren't so sticky. And as I said, they're not so reliable. Or dynamic. But who said that a tilt switch has to have a liquid metal in it? Yes, there are rather interesting solutions available when it comes to tilt switches.