Problem Hantarex Power Supply US250 no 120V

[Robotgreg]

I'm loking for someone who can repair a Hantarex Power Supply US250 power supply for me please.

Basically it's not outputting 120V to power the monitor in Robotron. The 240V is fine. Have checked fuses and all OK and Bazfish has kindly has come and checked too and couldn't find anything obvious. It was working fine but I then sent the chassis off for repair as was missing green but when plugged back in, no 120V supply.

So is there anyone on here who could repair it for me please? Will pay of course.

Cheers
Greg

PS there used to be a members services section on here but can't find it anymore as thought there might be someone willing to repair pcbs listed there.

 

[Retroman839]

You could message gunblade
I had same issue
Common issue with these ..
Seem to remember the big caps are most prone to be bad
But then knock on effect likley to blow a few more components

 

[Retroman839]

Voltage test points in this schimatic

https://www.arcade-museum.com/manuals-monitors/Hantarex%20Power%20Supply%20US250-300.pdf

 

[Alpha1]

@gunblade repairs them as well as monitors afaik.

 

[Robotgreg]

Thanks, will message Gunblade and see what he says.

 

[Robotgreg]

Voltage test points in this schimatic

https://www.arcade-museum.com/manuals-monitors/Hantarex%20Power%20Supply%20US250-300.pdf

Thanks have found that but it's a bit beyond me.

 

[Retroman839]

Thanks, will message Gunblade and see what he says.

Yeh contactin grant good idea .
There are clear voltage test points
On the schematic , good schematic that one nice and clear and has sign waves for scope.
I think replacing the power supply is an option but new connections required.

You could replace with
A Solid 240-125v isolation transformer
Seems a safer way to get 125v
than these transforms,, then use a suzzo happ or similair well respected switch mode arcade power supply for your
5/12 -12

But then all new connections required also

 

[Robotgreg]

Thanks, yeah, that could be an option if I can't get the original fixed but would prefer not to have to bugger about with different connections.

 

[Retroman839]

Thanks, yeah, that could be an option if I can't get the original fixed but would prefer not to have to bugger about with different connections.

Yeh I know ..
But it is satisfying when you have.
And include the inline fuses for protection .. too..
New power suppLy = peace of mind

 

[Lurch666]

I replaced my hantarex 250 with an isolation transformer for the 120V and a switcher for the other jamma voltages since I read somewhere that if a hantarex 250 PSU fails it could taker the monitor out as well and finding a replacement CRT can be tricky and expensive.
There's a thread somewhere on this forum about how I did it.

 

[cliff_poole]

Dry joints are very common on these. If you are taking it out anyway, it might be worth a quick look, see if you have any bad enough to be visible.

 

[Ordyne]

Dry joints are very common on these. If you are taking it out anyway, it might be worth a quick look, see if you have any bad enough to be visible.

This, they’re right crusty old barstools, the transformer solder pads will be as crust as!

 

[Robotgreg]

Expect this was the problem. Sent to Grant who fixed it same day!, just waiting for it to come back as asked him not to send it back until after Easter as not going to move much at moment but he did say solder joints on transformer were dodgy.

 

[pooman2084]

Robotron will live again! Awesome!