😁

Mouser do list the F47 transistor. Not stocked, but they obviously can get it for me, so this is the way I am planning to go unless someone else links me to somewhere else.

[URL]https://nz.mouser.com/ProductDetail/Shindengen/F47W60C3-7100?qs=XynAqUfUlD0wxRHAKdLFNQ%3D%3D[/URL]https://Mouser do list the F47 trans...NQ%3D%3D[/URL]

Yes, that was my thinking also! 😛
I was a little dubious about that idea, so I thought I would ask.
You've just convinced me NOT to do that. 😁

I'll just continue to look around at the components as listed, and check that they are all within what they should be.

One thing about the schematic from the Panasonic service manual that baffles me a little, is that caps and resistors have their values stated, but the semi's don't.
The codes listed on the schematic, are nothing to do with the part number at all. I wonder why Panasonic did the schematic...

@ CapLeaker - Thanks, will do. Nothing is burnt out or showing signs of damage, but then, neither was the MOSFET! Is it acceptable to power the board with both MOSFETS out, so I can measure voltages on the gate drivers etc, or would that be a big no-no and cause more damage? 🤔

@ R_J - Thanks, I will also test those resistors. 😎

According to my research, these MOSFET's are obsolete anyway, so I can't get them through any of the legimate parts houses - everyone but Mouser does not even know of the part number, and Mouser says they have no stock. The Shindengen...

Q1204 short-circuit across ALL THREE PINS. With Q1103 removed, short still present on PCB, with Q1204 removed, short is GONE from the PCB.
Testing the legs of Q1204 reveals the dead-short across the device. Progress! I will replace BOTH of these MOSFETS, unless someone thinks it's OK to reuse Q1103, but IMHO, that device was probably stressed and has had a service life also, so I am of the mind to replace them both, so both sides of the SMPSU driver are then new devices. Members please let me know your thoughts.

Excellent, thank you. I was sniffing around the area of Q1103 and Q1204 when you posted, as those are obviously high-power MOSFETS, so.... I will pull both of those out later, and see if the short has gone, if not, will do the caps next.
I love a good mystery! 😁

EDIT: I will pull one MOSFET at a time, and test to see if the short has gone. If either MOSFET is dead, I think it would be wise to replace BOTH of them at the same time, with new ones.

Hi. 😀

Measuring across the bridge with it out of the board across + and - pins shows no short - it measures open circuit.
Measuring across the PCB where the bridge normally sits, across + and - tracks shows dead-short(zero ohms!)

That's not good..... 😁

I'll proceed along the lines you suggest, which was pretty much what I was going to do anyway, but I posted the thread, in case someone else had seen this fault before, and might have been able to tell me what they found as the cause. I just continue tracing. I will let the thread know, if I find...

Hello everyone. 😀

As per thread title, this unit has a serious SMPSU fault. It blows F1001, which is a 10A M205 in the phase from the mains input.
Very first thing I tried, was simply replacing the fuse, but the replacement ceramic fuse blew immediately.

Looking at the schematic for this PSU, I then removed what I thought was the next likely candidate: D1001 - the HV main bridge rectifier.
This isolated the fault(no longer blows the main fuse), but does not point me to the actual fault.
There are no devices that have exploded or otherwise show signs...

Hello. 😀

I run a small one-man electronics repair business, here in...usually...sunny New Zealand. I am sure I will be able to make use of this forum. I also design my own PCB's for various things, and write code for MCU-based projects.