Quote:
Originally Posted by tdvab
While waiting for the replacement to arrive, I decided to resolder the pins securing the original chip to the board before pulling the original.....and......that fixed it!
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I've fixed hundreds of those Sonys, and my guess is that you will have to replace that MCZ chip soon.
One of the tricks we used to identify a bad MCZ chip was to simply heat it with a heat gun or a wide blade soldering iron across the top of the chip. If it started, I changed the chip. Heating them would sometimes restore them for a short amount of time. While it's certainly possible you had a bad connection that you fixed by soldering, I can honestly say that I never saw bad solder on the power board.
Some info from the field for site posterity:
There are two board versions - the brown and the green. The brown may have been in the DA1 and the green in the DX series, but I don't trust my memory like I used to.. The brown board is a single side board and it's very easy to replace the chip conventionally. I normally would put down a little liquid solder flux and use Chemwick to clear the pins.
The green board is a double sided affair and the solder goes through the lead holes and stops on the component side. It's a lot harder to replace the chip on the green boards. I used to add some chipquik to the original solder along with flux, then hot air the chip out of the board. It could also be wicked out but I preferred the hot air. I wouldn't use a spring loaded solder sucker on these as the recoil could damage a trace.
I never did this, but some guys would clip the pins of the chip from the top of the board with a *high quality* pair of angle cutters, then heat and remove each pin individually. Alternatively, you could also use a Dremel (if you have the swing room) with a cutoff wheel to cut the pins at the chip's body. Don't rush the cut lest you snag the pin and pull it, and don't go too deep!!
Towards the end of the Sony DTV era, there were TONS of counterfeit chips around. At the end, the only place I would trust to buy any Sony chips is B+D
https://www.bdent.com/. I don't know if they have any originals left. The counterfeits would either not work, fail shortly after power up, or trash other parts around the chip. Careful with sourcing the MCZ chips.
Lastly, 98.136 percent of Sony TVs that came in for repair that had a power supply problem only needed the MCZ chip closest to the flyback, so I would only install the one chip - not both.
John