Power supply repair - HELP NEEDED

[The Black Adder]

Hi all.

I have a PPM unit (like a VU unit) which has a little problem.

If I switch it on from cold all the lights light up and all is well but after 30 secs or so the whole display starts to flash in a regular way (about 1/2sec intervals) If I listen carefully I can hear a little ticking noise inside which corresponds exactly to the flashing display.

Also, when I turn it on from cold and all the lights are fine but if I give it a little tap it will start ticking/flashing again.

Could anyone tell me what this could be? Anything simple to check? - I've checked all of the cables and managed to isolate it down to the power supply as the rest of the unit is just simply plugged in to it. So with the circuit supply plug removed the supply still ticks.

Or better still, could anyone repair this for me? It would be a shame to get rid as it's built really well and was really expensive new.

Below is a pic of the insides. The power supply is the box (with the vents) on the right hand side. I could possibly take some pics of inside it, it looks easy to remove as it's quite modular.

Also, just out of interest, the IEC inlet says 'Auto Ranging', does this mean it automatically adjusts from 110/240v accordingly?

Thanks
Jo

[Firebottle]

Looks to me like it is a switching power supply inside that case. My guess is the main reservoir capacitor is past it, dried out, quite easy to replace if it is.

It is a fairly common fault with older switching supplies.
Do you have a multimeter Josie? Read the output voltage of the power supply, sounds like you will find it jumping up and down.

You could send the supply itself to me to be fixed if that is the case.

[sq225917]

Open the PSU section metalwork, chances are it's an off the shelf SMPS unit with a standard output voltage range, most likely a simple drop-in swap.

[The Black Adder]

Thanks, Simon.

Yeah.. I hope it's something simple.

It's on it's way to Alan at the mo so hopefully he can fix it.

The unit is from the late 90's as far as I can see so I hope it's fixable.