Looking for schematic of JVC QL-7 power supply

[DaleEMartin]

(Long time lurker, first time poster...)

I have a JVC QL-7 that I bought a few years back and have really enjoyed. Recently it stopped powering on. I dug into it and the power transformer's primary measures open. (Not sure why that would happen - we didn't have lightning or anything like that. Seems weird to be age related, although admittedly it's 46 years old.)

I did some googling for the service manuals, for replacement transformers, etc. but so far I'm coming up pretty much empty. I was thinking if I could at least see the schematic of the PS I could see if I can find a suitable replacement transformer. I've looked at other JVC turntable service manuals and this transformer is different than the others I've seen. It's 120VAC in, and it has two separate secondaries, where the others I have seen only seem to have one.

Any leads, thoughts, pictures of the schematic, etc. would be greatly appreciated!

 

[ralphfcooke]

I've had a look at a few similar JVC turntables, and I suspect the main secondary is around 28.5V, and the second is for a neon strobe.
Here is a section of the schematic for the QL-A7, which has similar specs if your local line supply is a bit hot then it's possible that a
thermal fuse embedded in the primary winding has popped

 

[DaleEMartin]

Thanks! In fact I run my tube gear on a variac because our supply line does run pretty hot.

I have a couple of dumb follow-up questions.
1) what is the point of the 1:1 secondary for the neon strobe? Do I need that?
2) 28.5V - I guess that’s RMS. So would this transformer work for this application?

(https://www.jameco.com/z/PT-2866-R-...yRgQ7_a3hEDM3wjilD5f0PwrRwK7kUasaAtuhEALw_wcB)

 

[ralphfcooke]

Yes, should do OK, but the open circuit voltage may be a bit higher.
As the TT uses so little power I'd be inclined to go for a 25V transformer, especially if your supply is on the hot side.
the 1:1 output for the strobe is for safety, you don't want live mains around the inside of the TT