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FrozenGate by Avery

my 1st effort at building a driver - help

Hmm. Based off of your circuit, it looks like you have it all coming out of your output in (the middle pin), whereas it should really all stem from your adjust pin. Can we see the bottom?
 





Hm... that's interesting. Everything *looks* fine. But it's hard to tell. Mind drawing me a diagram or something so that it's more clear (of both the front and back side) or something so I can make sure? Because the issue that you present, having to short it, in order to make it work, seems like it shouldn't be happening.
 
sorry, forgot to metion above, i brought a new regulator and that solved it, have just stripped it and soldered it without using a pcb just wires etc and im getting .118 with the load test circuit using a DMM set to volts, still not the max 250ma i should be getting, will go to my local store tomorrow see what other pots they have incase this one is a duff.
checked the colouring on the resistors and there fine there 10 ohm as they should be.

Drawing you a diagram - the diagram Laserbee posted is how its wired up.

cheers
 
Hmm... the only other problem I can imagine is... how many volts does your power supply put out?
 
hmmm yeh, 4.8 volts am using 4 AAA's, i see it says 7.2 volts ideal on that diagram.

problem ?

Cheers
 
Yes! The LM317 requires at least 3V overhead from the Vf of your load. The load you are using (your test load) has four diodes in series. Those diodes generally have a Vf of 800mV each. In series, that gives you 3.2V. In order for your driver to work properly, you will need 3V + 3.2V = 6.2V. It is recommended that you have around 7.2V so that you can have some overhead to work with!
 
Hello, well thank you very much all sorted think its pretty much there - am getting 11mA min and 246Ma max Tho that is using a 7.2v rated 5000mah lipo battery from my rc cars on a multi meter they put out nearer 8.4v,so need to find some power pack of the same power but much smaller.

Thanks alot for all your help.

Cheers

Rocky
 
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