HX-10 Faulty transformer

By jonwarby

Supporter (3)

jonwarby's picture

05-12-2021, 13:20

Hi everyone, I am an avid retro computer user and collector. Last night I got my first MSX. It's a lovely looking machine and it came with a few tapes and cartridges. It's a euro Toshiba HX-10. Purchased off of Gumtree as "it was working when we put it in the attic" I've got it home and tested the voltages on the connector to the motherboard with the motherboard unplugged.
I'm getting
+20v AC on blue
+2-3v AC on grey and brown when I was expecting to get around 9v

I assume this suggests that the transformer has had it. What are people doing to replace? Are you getting an equivalent AC transformer that can fit in the space or putting in a DC transformer and wiring it differently.

regards
Jon

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By Manuel

Ascended (18392)

Manuel's picture

05-12-2021, 14:38

I'm not a hardware guy at all, but to be sure I'd also check the DC output, there should be 5, +12 and -12V as far as I know.

By Repair-Bas

Paragon (1133)

Repair-Bas's picture

05-12-2021, 15:59

If you need parts, please sent me a message. I have most parts in stock

Cool Cool Cool Cool Cool Cool

By jonwarby

Supporter (3)

jonwarby's picture

05-12-2021, 17:05

Thank you for the reply. I've struggled to find any sort of service manual for it but reading previous posts and trying to interpret the Japanese PSU it seems to be an AC only PSU and I assumed the DC conversion was done on the motherboard.

By jonwarby

Supporter (3)

jonwarby's picture

05-12-2021, 17:07

Repair-Bas wrote:

If you need parts, please sent me a message. I have most parts in stock

Cool Cool Cool Cool Cool Cool

Will send you a PM to see to see what replacements you have. Would rather replace with something newer as anything of that age is probably going to have a limited lifespan.