powerpod 740 help needed

Phonic Powerpod 740 problems

Hi everyone,

I've managed to repair my 740 with the assistance of the contributor ( ShorBird ) who posted the repair kit details. He was able to mail me the schematics of a similar model.

In the end, I worked through the circuit and replaced everything that had blown - not just the bits in the kit...

I took all the transistors and diodes out and tested them separately - then I replaced the ones which tested OK to be sure...

I still have no idea what caused the problem - the circuit seems to be a reasonable design and has all the obvious protection in place, etc.

I had to replace the following parts:-

The pair of IGBT switchers
The four driver transistors
( 100Volt 1 watt TO-92 - 2 NPN & 2 PNP )
The four transistors in the PWM feedback loop
( 60 Volt 300mW TO-92 - 2 NPN & 2 PNP )
The 15 volt regulator on the startup supply ( 7815 )

Plus all the diodes in the kit

All the small transistors are hard to get, but if you look for the data sheets on the web, they aren't anything special.

I replaced them all with generic parts which I could buy easily

I confused myself by looking for DC on the output fuses before realising that they are in the AC lines from the transformer...

Total cost of the parts was about £10 and the unit is now 100% OK.
 

ariereij

Member
2011-02-20 11:46 am
Could anyone mail me the schematics (or preferably the complete service manual) too?
I was given the version with a switching power supply, som som copnent have already been removed, most likely because of short circuit problems.
Can anyone help?
regard ARie (neeby)