Electronic SPDT switches

Would not that be an OptoMosfet?

You are reinventing the wheel. Look up "Analog Switch". There are also analog multiplexers, which are made of a few of these. which are more like what you are proposing.

Check

Cheers! Rich

reinventing the wheel? I wasn't inventing nothing just wondering ;) (and theres nothing wrong with reinventing something either ;) I'm talking about specifically using electron ballistics to do this and not some other method. Analog switches uses transistors and such that are based on different principles?

AD

But these are based on semiconductor methods and not electron ballistics? I'm specifically talking about using electronc ballistic methods.

say I have a gas chamber with two anodes and one cathode and an external electric field... I Should be able to determine with anode I would like the current to flow to by controlling that field. Replace the gas with a conductor and it should probably work too(maybe not though).

I'm not trying to come up with some new switch but just wondering if it would work or not and if there was anything like it(not the switching itself but the method)...

AD

wouldn't that use light or something?

AD

This is essentially what a beam modulation tube does (using a vacuum).

However these types of device cannot exist using a conductor (how do you create an electric field in a conductor?) or even a semiconductor (the mean free path is too short for electron inertial effect to be used).

See

A beam modulator is a two anode electron tube with deflection plates to determine where the electrons go.

kevin

? what causes current to flow in a conductor? the potential is just the electric field(well, the gradient of the potential...). Its also been shown that putting an electric field perpendicular to a conductor causes charge seperation or something like that?

yeah, I figure its pretty easy to do in a tube but was wondering about a conductor.

Thanks, AD

So what? Whether you focus on the contacts (electrodes) or the crossbar (vacuum/bulk), a switch is a switch.

How about magnetic instead of electric field as in Hall effect?

Hall effect A/B switch? Probably insufficiently sharp switching action (too leaky) to be practical or somebody'd be selling them by now.

Mark L. Fergerson

Ok, AD, The problem has to deal with field theory, specifically, there are no magentic fields (or at least gradients) in a conductor. The conductor CONDUCTS the magnetic field, so, there is no difference in the field on one side of the conductor as opposed to the other (Yes, I know that is not exactly correct, but in analogy, it is the best explanation I can come up with... 8-) )

So, no, you can't steer the electrons in a conductor with an external magnetic field.

Charlie

not really. I'm not interested in switching but just the concept. A big difference. I didn't ask how to switch anything but if it was possible to do it the way I described.

I suppose that would work since a magnetic field would extert the same force(but would just have to rotate it 90 degree's.

probably. I figured that since most electrons are going about the same speed in a conductor that it wouldn't be to hard. I'm not saying its practical or anything but was just wondering if it was possible to do... I suppose I could build one or something but I got otherthings to do at the moment.

AD

heh, what about an electric field? (I didn't mention magnetic fields ;) I read somewhere that if, say, you have a current running through a wire and you put an electric field across it then the electrons will move to one side of the conductor...

something like

------------------------- ->

------------------------- ->

where the electrons are flowing in the direction of the arrow.. then put a field across them and it sorta becomes

----------------------- ->

where one side of the conductor is + and the other is -. Its the same as if you had a rod with some electrical charge on it and then put an electric field on it in some way... the charge would position itself across the conductor(or maybe it needs to be an insulator? ;/) to minimize the total energy or something like that.

it probably wouldn't be to hard to test it out(though I'm not sure of the required currents and voltages needed)... i might try it some day just for fun ;)

AD

May be you should try and share your findings. But you may need a awesome electric field to deviate the electron in a conductor. The metal is a good shield against that field. This is why FETs have been designed, just a tiny electric field is needed to deviate or block the electron flow.

Dan