Sega Blast City PSU - Voltage Support

[itsmedario]

Hey All,

I recently recapped my Blast City PSU and decided to test the voltages.

I've completely maxed out the 12v potentiometer to get these readings.

I completely reduced the 5v potentiometer to get these readings.

The readings I'm getting when connecting a RetroCastle Mister Jamma are the following.

The readings I'm getting when connecting a CPS2 are the following.

Are these safe? If not, what can I do to adjust them further?

Thanks in advance.

 

[nem]

There is no 12V pot on a Blast PSU. There is a pot for the 3.3V rail.

12V can be whatever, 11 or 13, it doesn't matter.

Set the 3.3V pot to center. Is the 5V still high with Mister?

Can you take pictures of the work you did and also list the capacitors you installed?

 

[Ape Cosplay]

How well are those LCD voltmeters calibrated? I always have to realign them by 0.1/0.2V.

 

[itsmedario]

There is no 12V pot on a Blast PSU. There is a pot for the 3.3V rail.

12V can be whatever, 11 or 13, it doesn't matter.

Set the 3.3V pot to center. Is the 5V still high with Mister?

Can you take pictures of the work you did and also list the capacitors you installed?

Post pictures and answer your questions shortly.

 

[itsmedario]

How well are those LCD voltmeters calibrated? I always have to realign them by 0.1/0.2V.

It seems to be pretty accurate. I was wondering the same myself and used my multimeter to take my own measurements and both gave me the same numbers.

 

[Thomas]

Do you mean maxed out the 5v and reduced 3.3v? Those readings might be low if the 5v is at max. Between the PSU connector, the JAMMA connector, your meter, and the game board JAMMA connection there are plenty of places to lose voltage due to dirty or oxidized contacts. It's a good idea to clean all of those if you haven't already.

 

[itsmedario]

There is no 12V pot on a Blast PSU. There is a pot for the 3.3V rail.

12V can be whatever, 11 or 13, it doesn't matter.

Set the 3.3V pot to center. Is the 5V still high with Mister?

Can you take pictures of the work you did and also list the capacitors you installed?

Please let me know if you require additional pictures.

I purchased my cap sets from Arcade Parts & Repair. Do you want me to provide the list of caps they sent me?

Let me put this back together and I'll set 3.3v to the center and see what reading I get.

 

[itsmedario]

Do you mean maxed out the 5v and reduced 3.3v? Those readings might be low if the 5v is at max. Between the PSU connector, the JAMMA connector, your meter, and the game board JAMMA connection there are plenty of places to lose voltage due to dirty or oxidized contacts. It's a good idea to clean all of those if you haven't already.

How would I go about cleaning the contacts?

 

[itsmedario]

Here are some new readings.

Both potentiometers maxed out.

5v dropped to the lowest setting and 3.3v maxed out.

Both were reduced to their lowest setting.

 

[Thomas]

How would I go about cleaning the contacts?

Do a search for cleaning JAMMA contacts. You'll find different methods and opinions and you'll have to pick one. But if you are getting 5V with the 5V potentiometer turned all the way down with the CPS2 connected then the contacts are probably all fine.

P.S. that 3.3V is for JVS and you can ignore it if you're only using JAMMA. Put the potentiometer back to center and leave there or set it to 3.3V if you have a multimeter. 12V is for audio and it doesn't matter if it's a volt or two off in either direction.

 

[itsmedario]

Copy.

I've been more concerned with the mister aspect of it all since I'll predominately be running a mister solution long term. I was reading on a thread that dialing in the 5v and 12v for the mister is pretty important but I can be wrong.