Page 1 of 2 12 LastLast
Results 1 to 25 of 41

Thread: Blast City, no video

  1. #1
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348

    Blast City, no video

    Hey everyone. I just got my first cab a Blast City wired for JAMMA. It has the Sega 600-6738-21 loom.

    When I power it on, I get sound but no video at all. I can hear the little initial "hum" of the monitor when it first powers up, so I think the monitor is receiving power.

    I've looked at the wiring diagrams, the FAQ, etc, can't find anything obvious. No leaking goop either.

    Any ideas on what I can check?


    Here is some pics of the cab and the wiring: http://imgur.com/a/YP3LO
    Slug 2 > Slug X

  2. #2
    BESTEST Buttrider in chat.
    Officially No.10 at Schmups.
    DIG it Brethren!
    Chempop's Avatar
    Join Date
    Oct 2010
    Location
    Massachusetts

    Posts
    3,271
    Looks like a ms-2933 or ms-2931 auto sync chassis, can you confirm which?
    I am only familiar first hand with the ms-2930 manual sync ones, but I know many others here have auto-sync like yours.

    Have you tried more than 1 PCB?
    Last edited by Chempop; 08-22-2015 at 06:58 PM.

  3. #3
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    I've tried four pcbs now: CPS2, DDP DOJ, ESP Rade and Demon Front (pcb, not a pgm). All have audio and input works.

    I'm pretty sure it's the auto syncing chassis. the bass fishing manual shows three dipswitches for picking sync, but I can't find those dipswitches anywhere, making me think I have auto sync.

    I'm not convinced anymore that the monitor is making any sound at all. I think the sound I am hearing is the fluorescent tube in the marquee warming up. So it's either completely dead, or perhaps the connection to the PSU came loose. I'm going out to look into that now.
    Slug 2 > Slug X

  4. #4
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    One more thing, it has the versus kit. And initially the versus kit was running a VGA cable into the monitor. I figured that's not needed and unplugged as much of the versus kit as I could.

    But maybe this was the slave in a versus setup, so something about the JAMMA loom isn't connected?
    Slug 2 > Slug X

  5. #5
    Fug:DDDDD
    Pasky's Avatar
    Join Date
    May 2013
    Location
    USA

    Posts
    2,933
    Having had a similar issue, willing to bet it's the Chassis.

  6. #6
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Quote Originally Posted by Pasky View Post
    Having had a similar issue, willing to bet it's the Chassis.
    What did you do to fix it, replace the chassis?

    I just confirmed with my friend the cab was working fine at his place. I drove it from his place to mine today (15 miles away). Strapped down very well and well padded in the back of a uhaul truck. So something probably broke on the drive. Damn.
    Slug 2 > Slug X

  7. #7
    Fug:DDDDD
    Pasky's Avatar
    Join Date
    May 2013
    Location
    USA

    Posts
    2,933
    Ya, chassis had to be replaced. Cap blew from what Chris told me but he took care of me. Check the neckboard, see if you broke the yoke during the drive or something. Do you see any neck glow?

  8. #8
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    where'd you get the chassis from? I might just get a whole new monitor, but can't imagine they are easy to get.
    Slug 2 > Slug X

  9. #9
    Fug:DDDDD
    Pasky's Avatar
    Join Date
    May 2013
    Location
    USA

    Posts
    2,933
    Cdamm provided a replacement. I doubt he has spares. Yours probably just needs to be recapped unless the flyback is dead. Unsure of any place that replaces chassis. You can't find those MS2931's new anymore I tried =/.

  10. #10
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Thanks for the help guys.

    I think I'm just going to start taking the cab apart because it's filthy and needs to be cleaned bad. Once I get the monitor out it will be easier to troubleshoot.

    It sounds like I can use a wei ya chassis. I haven't found any place to get a new monitor though. If anyone knows of any I'd love to hear it.

    I'm also going to track down an xbox 360 vga cable and hook it up and see what happens.
    Slug 2 > Slug X

  11. #11
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Well, the neck looks fine to me. Now that I have the monitor out of the cab, I should be able to track down the issue

    Slug 2 > Slug X

  12. #12
    BESTEST Buttrider in chat.
    Officially No.10 at Schmups.
    DIG it Brethren!
    Chempop's Avatar
    Join Date
    Oct 2010
    Location
    Massachusetts

    Posts
    3,271
    I’d start by just reconnecting the RGB line and all the cables to the blast’s I/O board.
    Then I’d check with a multi-meter that the game is getting a steady 5.0V (approx).

  13. #13
    Art of Typing Wiz
    codecrank's Avatar
    Join Date
    May 2011
    Location
    [+=..]

    Posts
    2,330
    Quote Originally Posted by city41 View Post
    One more thing, it has the versus kit. And initially the versus kit was running a VGA cable into the monitor. I figured that's not needed and unplugged as much of the versus kit as I could.

    But maybe this was the slave in a versus setup, so something about the JAMMA loom isn't connected?
    since you have a jamma loom and the vga splitter board plugged in, you have the master cab. the slave doesn't even need a loom. would's hurt to disconnect and reconnect your loom in, I've had one cab delivered with it loosely attached.

    did the video work prior to removing the versus kit ?
    did you check for neck glow before taking the monitor out ?

    anyways here is something to get you started. http://www.retrovicio.org/ficheros/t...rFlowchart.jpg

  14. #14
    3t3rn@l n00b
    Mugicha's Avatar
    Join Date
    Aug 2011
    Location
    (・へ・)

    Posts
    3,859
    hey buddy, this might or might not help but I had an issue a little while back with my Blast where I was getting picture but no sound, and my voltage was fluctuating very low. I took out the PSU and cleaned all the contacts and pins on the connector. I immediately got the sound back and the voltage remained steady. It has also run flawlessly since and that was over a year ago. I realize your symptoms are a little different, but it couldnt hurt to try cleaning the contacts on the PSU connectors. Best of Luck man.
    Quote Originally Posted by cdamm View Post
    we barely even talk about neo here.

  15. #15
    SouthTown StreetSweeper
    pulstar's Avatar
    Join Date
    Jun 2011
    Location
    Southampton, England

    Posts
    568
    When you power the cab up, do you get any glow in the neck? If you do then it is more than likely a wiring issue with the RGB signal. If there is no neck glow it could be the chassis or the power wiring to the chassis. The sound you're hearing could be the degauss coil activating when you switch the cab on.

    Do you have a multimeter? Once you've check the wiring, check the chassis is actually receiving the voltage it should.

  16. #16
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    There is no neck glow.

    I have the cab almost completely taken apart. But there are two screws holding the two halves that I cannot get out to save my life. My el-cheapo drill wasn't cutting it, so I ordered a decent drill. Once I get the cab apart, I'll be able to fully remove the wiring, then set everything up on my workbench and will start checking for proper voltage in the places suggested.

    Mugicha, thanks that is a good idea. I took the PSU out and completely cleaned it. It'd be fantastic if it was something that simple!

    codecrank, that flowchart is handy.

    Once I get the drill and get things going on the workbench, I'll update here again. Might not be until this weekend.

    Thanks for the help guys! I'm determined to get this thing running and have been reading up on monitor repair everywhere I can find.
    Last edited by city41; 08-25-2015 at 12:27 AM.
    Slug 2 > Slug X

  17. #17
    Astra Superstar
    joecommando's Avatar
    Join Date
    Jun 2010
    Location
    bellingham WA

    Posts
    824
    Quote Originally Posted by city41 View Post
    There is no neck glow.

    I have the cab almost completely taken apart. But there are two screws holding the two halves that I cannot get out to save my life. My el-cheapo drill wasn't cutting it, so I ordered a decent drill. Once I get the cab apart, I'll be able to fully remove the wiring, then set everything up on my workbench and will start checking for proper voltage in the places suggested.

    Mugicha, thanks that is a good idea. I took the PSU out and completely cleaned it. It'd be fantastic if it was something that simple!

    codecrank, that flowchart is handy.

    Once I get the drill and get things going on the workbench, I'll update here again. Might not be until this weekend.

    Thanks for the help guys! I'm determined to get this thing running and have been reading up on monitor repair everywhere I can find.
    Be careful plugging the monitor in to a wall outlet! all of the monitors ive worked with are 100v and you can fry them if you plug them into the wall. not sure if its the case with these as Ive never worked on one but just be careful.

  18. #18
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Quote Originally Posted by joecommando View Post
    Be careful plugging the monitor in to a wall outlet! all of the monitors ive worked with are 100v and you can fry them if you plug them into the wall. not sure if its the case with these as Ive never worked on one but just be careful.
    I'm going to plug the monitor into the blast's PSU. Basically I'm going to get the cab running outside of the cab shell, JAMMA loom and all.
    Slug 2 > Slug X

  19. #19
    Art of Typing Wiz
    codecrank's Avatar
    Join Date
    May 2011
    Location
    [+=..]

    Posts
    2,330
    the blast city PSU doesn't do anything special to the AC power it provides the monitor, other feed it through standard filter of course.
    the PSU and nanao chassis can operate at 110-120v just fine.

  20. #20
    Bunker Buster
    mr_b's Avatar
    Join Date
    Jun 2009
    Location
    Chicago, IL

    Posts
    1,461
    Have you adjusted the flyback knob labeled "screen"? If you slowly, and I do mean slowly, do you get anything? If if it just seems like the black screen is getting brighter?

    And to determine your sound being the lamp and not the monitor have you unplugged the wiring to the lamp?

    I recently repaired my 2931 chassis by replacing some transistors on the main monitor chassis board. Let's work thru the TS steps to get ourselves to the point that we know the chassis is the issue.
    Last edited by mr_b; 08-25-2015 at 09:11 PM.

  21. #21
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Quote Originally Posted by mr_b View Post
    Have you adjusted the flyback knob labeled "screen"? If you slowly, and I do mean slowly, do you get anything? If if it just seems like the black screen is getting brighter?
    I haven't done this, but I also have no neck glow. So with no neck glow, should I expect anything at all on the screen?

    And to determine your sound being the lamp and not the monitor have you unplugged the wiring to the lamp?
    Yup, I now have it running like this:



    Without a doubt, when I power it up, the monitor itself makes several "clicks", much like you'd expect to hear from a CRT PC monitor powering up, they sound like "correct" clicks to me. Also confirmed the wiring in general is OK. The CPS2's fan comes on, and the JAMMA edge is receiving proper voltage.



    I recently repaired my 2931 chassis by replacing some transistors on the main monitor chassis board. Let's work thru the TS steps to get ourselves to the point that we know the chassis is the issue.
    I'm pretty new at this, so probably working slow enough to be annoying. Tonight I was able to confirm both fuses on the chassis are in tact. I did that using continuity mode on my multimeter.

    I'm also confident that the AC power lead that goes in on the front of the monitor is delivering power.
    Slug 2 > Slug X

  22. #22
    Bunker Buster
    mr_b's Avatar
    Join Date
    Jun 2009
    Location
    Chicago, IL

    Posts
    1,461
    With no neck glow youre likely to need chassis work. But i think its most likely to something power related since there no neck glow. Looks for bulging caps as that would be easiest. Next youll need to source power transistors. Are you handy with soldering? If not dont undertake this you should send it to someone to fix for you.

  23. #23
    Fug:DDDDD
    Pasky's Avatar
    Join Date
    May 2013
    Location
    USA

    Posts
    2,933
    For sure, those caps on that chassis can kill you if you have no idea what you're doing.

  24. #24
    Gai's Trainer
    city41's Avatar
    Join Date
    Dec 2010
    Location
    San Jose area

    Posts
    1,348
    Yeah and I don't know how much good I can really do at this point. I'm pretty sure it's the chassis. I am looking for someone who can repair it, also on the hunt for a new one.

    If anyone knows of a good repair person, would love to contact them.

    If anyone knows of a good replacement chassis for a MS2931 in today's world of endangered CRT monitors (weiya? rodotron?) that would also be helpful.

    I may have found an entirely new MS2931 monitor, but it's a long shot.
    Slug 2 > Slug X

  25. #25
    Choi's Barber
    kuze's Avatar
    Join Date
    Apr 2013
    Location
    In the year 2248

    Posts
    2,211
    Quote Originally Posted by city41 View Post
    Yeah and I don't know how much good I can really do at this point. I'm pretty sure it's the chassis. I am looking for someone who can repair it, also on the hunt for a new one.

    If anyone knows of a good repair person, would love to contact them.

    If anyone knows of a good replacement chassis for a MS2931 in today's world of endangered CRT monitors (weiya? rodotron?) that would also be helpful.

    I may have found an entirely new MS2931 monitor, but it's a long shot.
    Quan at East Coast Amusements is often recommended from what I've seen, but I have no personal experience with the guy.
    http://www.eastcoastamusements.com/contact/

    Also grendelrt might be willing to part with one of his spare chassis... worth giving him a PM to see.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •