Sega Model 2B Help

[MrBob]

Hi there

Got a Sega Model 2B with Sonic Fighters Rom board, Its now got a few issues I'm wondering if any one can help me with.

1st thing I noticed was the settings and high scores were not getting saved after powering down, now when it starts up it runs for a few mins then freezes.

Its set up with a generic 12/5v power supply which is showing 12.5 and 5.5vs when the games running and connected to a PC monitor via a upscaler.

Is there a repair service for these boards ?

Thanks

Robert

 

[AMS]

These boards are really doing crazy things if power is not right and also they can t take higher voltages

Make sure you measure 5v and 12 at the filter board of the m2 running under load

 

[MrBob]

These boards are really doing crazy things if power is not right and also they can t take higher voltages

Make sure you measure 5v and 12 at the filter board of the m2 running under load

Just checked, the PSU is maxed out 5.5v at the PSU but only 4.8 at the filter board

 

[lix]

Probably two separate faults here, the loss of settings is likely the supercap (the only stubby fat green cylinder thing) on the CPU board has failed due to age, that's a fairly easy replacement. The game freezing after warmup could possibly be a dry joint or lifted leg on a surface mount chip somewhere, literally anywhere and tough to find.

Other than Ken at irepairsega.com then I don't really know anyone who offers a public repair service. It's unfortunately an expensive hobby with these boards.

 

[MrBob]

Probably two separate faults here, the loss of settings is likely the supercap (the only stubby fat green cylinder thing) on the CPU board has failed due to age, that's a fairly easy replacement. The game freezing after warmup could possibly be a dry joint or lifted leg on a surface mount chip somewhere, literally anywhere and tough to find.

Other than Ken at irepairsega.com then I don't really know anyone who offers a public repair service. It's unfortunately an expensive hobby with these boards.

The super cap is a good idea, will look into that.

The cutting out seems to be down to the filter board only getting 4.8vs, I found a connector on the 5v line from the PSU that if you squeeze hard the filter board goes up to 5.2vs and doesn't cut out so it seem that's the issue there.

Thanks for all your help guys