Hello. That looks like a rebadged Panasonic PV-4750. The 4760 is the hi-fi stereo version. Be sure to check the electrolytic caps in the power supply before using the machine.

If this is the power supply your machine has, I can post the full schematic if you need it.

Fivos

yep that's it right there, I still need to check the switching transistor in the power supply (Q1) because this power supply only has 2 transistors in it overall and the one of them is the Switching Transistor (the transistor attached to the heatsink) that's the only part I haven't changed yet that I suspect might be still causing the VCR to blow fuses.

Did you disconnect Q1 from the circuit and measure it? Are the zener diodes OK?

Yes, all the diodes checked fine yet. The only diodes that checked bad was the bridge rectifier, which I already changed that out for a modern replacement the switching transistor I have not had a chance to check yet, the way they did the power supply in this VCR is that you have to disconnect a ribbon cable that's connected in a strange manner and then undo 2 solder blobs holding it to the main circuit board and then bend a retaining tab and then gently remove it from the main board without cracking the main board.

Yes I've seen the process of removing the power supply in these machines. What I'm thinking is perphaps the caps in the primary side failed and caused the oscillator to go into a runaway condition and that caused the output voltages to rise up way too high to the point where the crowbar shorted and took out the switching transistor and other critical components. I've heard this can happen with Panasonics of this era.

Yes, I'm pretty sure that's what happened as quite a few caps had puked their guts onto the board which had unfortunately damaged some of the traces, I checked the dioded including the zeners and they all checked as they should thankfully, like I said the only diode that seemed to of failed was the bridge rectifier.

What about the circuit protector PR1 (ICP-F38) in the secondary side across the 5 volt rail? Does it also measure bad (open)?

OK, so I finally got around to taking the transistor out of my VCR, and it seems its a "proprietary" transistor (it was a transistor that was made by Matsushita themselves and it doesn't seem to have a cross reference to any currently made transistors, at least not that I could see.)

Does anyone know what a 2SC3870 NPN Triple Diffusion Planar Transistor cross-reference to?

I figured it out. I had a transistor from a junker VCR and its working now. :thmbsp: :yes: :music: