reed relays

[JudgeKane]

Ok, found some 5v reed relays in the UK (for the board/LED - keeping it bright), now I have the option of "Reed Relay 5V SPST" or "Reed Relay 5V DPST"...

Which should i be buying, and if you can put it in layman's terms, whats the difference?

I know it's to do with the switching, one just "pings a signal" and the other stays on...maybe lol i'm not sure

[Silver Serpent]

You appear to have asked a question in a vacuum, so to speak. We're going to need a good bit more information before answering.

http://en.wikipedia.org/wiki/Relay and http://en.wikipedia.org/wiki/File:Relay_symbols.svg can help with understanding the difference between SPST and DPST.

What exactly are you wanting to do? Most uses of relays in the lightsaber hobby have been changed to use transistors for the sake of durability.

[JudgeKane]

Basically I've just put a economy sound board into my 1st saber (2nd get's one soon) and just been reading through the sound forums about sound boards and getting the LED to run brighter, and the relay idea seemed like a good idea, I shall have a look into transistors and have a re-think lol
just found this http://forums.thecustomsabershop.com...highlight=2010

What sort of transistor am i looking for? searched on a UK supplier and they have 18 different types lol

Low-Power, Low-Frequency PNP Transistors; BC558C, BC327, 2N5401
Standard Bipolar PNP Power Transistors; BD442, TIP2955, BD912 there's billions!!!!!! lol

[Sunrider]

Look at the data sheet it will show the difference. Ether should work. and make sure you get one that can handle more current than you need.

[JudgeKane]

I'm lost with these transistors they say weird things like -100mA...eh? lol

Think I might try the relay method, I understand how that works lol and they don't get flung about too much so should be durable enough...

[KuroChou]

For future reference, anything in electronics that says SPST, SPDT, DPDT, SPTT, DPTT... etc; is referring to Single Pull Single Throw, Single Pull Double Throw, Double Pull Double Throw, Single Pull Triple Throw, and so on.
The "pull" refers to the physical component of the switch, be that a button, toggle, signal (as in solenoids and relays), magnet (as in reed switches), or any other input device or sensor.
The "throw" is the circuit connection, which you're completing or breaking.
SPST means there's one button for one circuit, while SPDT is referring to a single switch that simultaneously toggles two different circuits.
On a non illuminated switch, SPST means only two pins, while SPDT means four (unless it's bi-directional, then it's six).
There will always be at least two pins for every throw, three if it's bi-directional.
In the case of a relay, solenoid, or illuminated switch, there will be two extra pins for the signal coil or LED power.

[Noyl Wendor]

If you look in the forums in tutorials you can find a couple of diagrams showing transistors instead of reed relays. Trust me the transistors work the best. Most of the time you can find them at RS. Its called a TIP42. Good luck.

[JudgeKane]

Thanks KuroChou, that was great, and i think it's actually sinking in

and thanks Noyl Wendor, I shall have a look over the next couple of days and give the transistor a bash then, looking at the diagrams;

The battery poss goes to the transistor then onto the LED, would this setup not need a buckpuck after the transistor or a resistor at least? (I don't wanna pop anything, i haven't sourced the LED's in the UK yet

[Don Se Wion]

You definitely need to add at least a resistor between the LED and the transistor.

The choice of the resistor depends on the LED type and color and the battery solution you are planning to use.

For reference you can check the LED resistor chart in the shop.

[JudgeKane]

I think i'll try running a 1000mA buckpuck and see what happens...i'll get some pics/vids up when i've had a go