hi,
I see that you agree the problem is with original PCB layout.
Your post #115 looks OK, it's not elegant but it should work, I would add a 100uF across the Vout to 0V
If you recycle any components, caps, diodes, check that they have not been damaged.
E

I checked alll the components, ( diodes were shot)

Made the pcb and wired it all up and....

It still doesnt work!

Im getting 0v output and 2.2A now??

 

Hello,

It looks like there is a short on the output.
Is the capacitor on the output OK?
Is the regulator still OK?

Bertus

 

its a new regulator so should be ok...

The cap is also new and testing ok.

Where is the short?

 

I found out that it is the eBay special volt meter that is causing my short!

I must have it wired incorrectly.

Anyone know how its supposed to be wired?

 

Hello,

Is there no short on the pads under C4 or the output connector?
I would not expect a short under R2, as the pads are more spaced.

Bertus

 

voltmeter

 

Hello,

Do you have a link for the volt/ampere meter?

Bertus

 

Its ok i had a swap around of some wires and its fixed and working

Thanks for all your help!!!

 

Ok so now i have an issue with it.

When i tried to change the knob on the potentiometer i accidentally pulled the center out.

I put it back in and all was working fine.

I had another laying around so decided to change it.... big mistake!

After soldered the new 1 in and switched it on a crackle and puff of smoke came from the pot and the voltage stuck at 32v.

I thought ok it was a dodgy pot so swapped back to the original and.... the same thing happened!!

I touched nothing else on the circuit so dont see why it would suddenly do this...???

Help??

Thanks

 

hi K,
It is possible that the LM317 is damaged.
Try this, in place of the pot use a 1K resistor and try a new LM317.
Your original pot may have gone open circuit when you pulled its innards out.

If that gives you a stabilised Vout, fit a new pot.
E