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FrozenGate by Avery

hi im new

Well heres a place for 10 cheap ones...http://cgi.ebay.com/100-Ohm-1-Turn-...ryZ58164QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

It depends if you have like 250ma going into it, it will get kinda warm, mine gets warm after about 2min but i never run it longer than that, if you put it in a heatsink or on a tec tho you can put alot more power into it like 400ma will get you about the most power it can give.


...lazer... ;D ;D ;D
 





400ma's??? I think this would be a quick death for the diode.
 
mclovin said:
ok well can you tell me where to get a cheap 100 ohm pot??... and do you know how much heat a diode fromstonetek electronics puts outt... im thinking of ordering one tonight? thanks alott
Click to expand...

You can get a 25ohm rheostat at RS. It's overkill since it is three watts but it will do the job. Put it in series with a 5 ohm resistor between the output and adjust. When the rheostat is turned to no resistance, you will be supplying 250ma's to the diode. If you are going to use the LM317 then I suggest you click on the following link so you can learn more about it.

http://users.pandora.be/davshomepage/current-source.htm

Also do a search for it on google and you will find the data sheet.

The SenKat diodes are the best deal available and highly recommended.
 
Well considering if its on a tec it should work, that was the highest output power on hemlock mikes graph, its a chance it could burn out but if its cooled good it should be okeay, you could go down to 350ma if you wanted it is safer.

....lazer... ;D ;D ;D
 
Just like my open can running at 600ma's with a TEC ::) The point is let's not be overdoing the recommendations especially with new people. We all know 250ma's is a semi comfortable current to run the SenKat diode with...TEC or no TEC. ;)
 
Yeah if your new thats perfect but i for some reason love to push these, its a bad habit lol


...lazer... ;D ;D ;D
 
I also doubt that the 5K Ohm pot can handle the current used by the LD.
Ohm's law and the power law still apply. These are needed to even start to understand the driver circuit.

Mike
 
To figure out the wattage of the resistor and/or pot needed if using the LM317 you take the current and multiply it times the sense voltage.

P= 1.25 X I

So if you set it up for 250ma's, the wattage used would be .3125 watts.
 
Remember too that the wattage has to be disapated over a large portion of the pot's working area so you don't get a hot spot. The wrong value could make it dificult to control.

Mike
 
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