• Enraged
  • Embarrased
  • Drunk
  • Down
  • Depressed
  • Crying
  • Crazy
  • Cool
  • Cocky
  • Bemused
  • Awesome
  • Annoyed
  • Angry
  • Amused
  • Friendly
  • Geeky
  • Godly
  • Happy
  • Hateful
  • Hungry
  • Innocent
  • Meh
  • Piratey
  • Poorly
  • Sad
  • Secret
  • Shy
  • Sneaky
  • Tired
  • Wtf
  • Thanks Thanks:  0
    Page 1 of 3 123 LastLast
    Results 1 to 10 of 26

    Thread: Alvin G. & Co - Al's Garage Band goes on a World Tour

    1. #1
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      Alvin G. & Co - Al's Garage Band goes on a World Tour

      Started having a proper look at AGBGOAWT today. The first major issue seems to be power supply related - resets of the machine and the sound board dropping out so the music stops. Managed to record both earlier today: https://clips.twitch.tv/OilyPopularJayNomNom

      First stop the wiring diagram to see what's common between the sound board and the MPU:
      cabinetwiring.jpg
      So the MPU uses 20vdc and 5vdc, the sound board uses 12vdc and 5vdc. Let's have a look at the 5vdc side of things.

      On the PSU, I get 5.2v at PP2 on the orange/blue to black. On the MPU, that drops to 4.9v and occasionally 4.8v. When it's at 4.8v, right flipper or the auto plunge will cause a reset. Similar levels to the MPU on the sound board.

      So looking at the schematic:
      powersuply.jpg

      I checked the input to the 5v circuit and it's a shade over 9vac. There's a pot (VR2) to adjust the output of the 5v circuit. Turns out clockwise decreases the output voltage, anti-clockwise increases it. Dialed it up to 5.4v when unloaded and the game no longer resets.

      Played for a little while this evening and I'm still occasionally having issues with the sound dropping out, but the MPU is not resetting so that's good. The regulator is quite hot though, like burn my fingers hot, so I guess I really need to do some replacements on the PSU.

      Things still to look at:
      • Garbled DMD for some modes, animations
      • Sound drop outs
      • PSU maintenance
      • Hum that can be fixed by tapping the cabinet - something is loose
      • Left bump button doesn't seem to fire
      • Right bump button clashes with autoplunge coil
      • Flippers need rebuilding
      • Insert GI Isn't working.

    2. #2
      Autosteve is offline
      This user has no status.
       
      ----
       

      Join Date
      Dec 2016
      State
      Barden Ridge NSW
      Posts
      2,650
      Mentioned
      132 Post(s)
      Quoted
      1017 Post(s)
      Australia
      Alvin G formally Gottlieb, check all your grounds...Double up on them as a form of fault finding rather than disturbing what is there. If the problems go you know where to start looking.

      Pretty sure the 5 volt reg is the cheaper adjustable type used on Alvin Gs so it might be worthy of swapping but a bad earth with cause a reg to get hot as well which is worthy of noting.

      The reg should never get that hot. They do have thermal protection to shutdown if they run to hot and this will kill the 5volt till the heat drops off before resetting itself.

    3. #3
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      Quote Originally Posted by Autosteve View Post
      Pretty sure the 5 volt reg is the cheaper adjustable type used on Alvin Gs so it might be worthy of swapping but a bad earth with cause a reg to get hot as well which is worthy of noting.
      Bad earth or bad ground?

      That reminds me, another for the list:
      • Garbled DMD for some modes, animations
      • Sound drop outs
      • PSU maintenance
      • Hum that can be fixed by tapping the cabinet - something is loose
      • Left bump button doesn't seem to fire
      • Right bump button clashes with autoplunge coil
      • Flippers need rebuilding
      • Insert GI Isn't working.
      • Replace line cord


      The line cord has a 3 pin molex in it. Any thoughts on replacing like for like or removing it? I guess the pro is that it will disconnect if someone trips over the cord, but the con is that it adds another point of resistance and potential failure?

    4. #4
      Autosteve is offline
      This user has no status.
       
      ----
       

      Join Date
      Dec 2016
      State
      Barden Ridge NSW
      Posts
      2,650
      Mentioned
      132 Post(s)
      Quoted
      1017 Post(s)
      Australia
      Ground to each of the boards I meant. A hum that is fixed by hitting the cab certainly points that way too.

      Line cord change it. Wires will rip out of the Molex if you trip on the cord it and far to much chance the frayed ends of the mains line will short out before the line fuse.

    5. #5
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      Quote Originally Posted by Autosteve View Post
      Ground to each of the boards I meant. A hum that is fixed by hitting the cab certainly points that way too.
      Half only have 2 screws holding them for a start. :-/

      There definitely something off in the ground wiring - the menu and exit/service credit button intermittently stop responding. Pressing on the connectors on the PSU seems to fix that.

      Quote Originally Posted by Autosteve View Post
      Line cord change it. Wires will rip out of the Molex if you trip on the cord it and far to much chance the frayed ends of the mains line will short out before the line fuse.
      Cool. I figured the molex to make it more convenient to assemble at the factory and less useful to me. An IEC socket would've been a better option, but would've cost more too. New line cord on the list, and I'll bring it all the way through to the filter.

    6. #6
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      I'll fix this connector too. Without using these to stop the wires shorting: https://www.bunnings.com.au/ramset-7...of-25_p2260646IMG_20180517_143509.jpeg

      I wonder if that's why the insert gi doesn't work.

      Sent from my TA-1012 using Aussie Arcade mobile app

    7. #7
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      This chip on the DMD driver board looks a bit odd too...
      IMG_20180517_144136.jpeg

      Sent from my TA-1012 using Aussie Arcade mobile app
      Last edited by ajfclark; 23rd May 2018 at 12:17 PM.

    8. #8
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      Few more shots on the PSU. And the original position of the 5v pot.IMG_20180517_150958.jpegIMG_20180517_143518.jpeg

      Sent from my TA-1012 using Aussie Arcade mobile app

    9. #9
      maxi's Avatar
      maxi is offline
      is WOOHOO!
       
      Happy
       

      Join Date
      Apr 2013
      State
      SYDNEY New South Wales
      Posts
      926
      Mentioned
      46 Post(s)
      Quoted
      271 Post(s)
      Australia
      Exciting - following this. I got offered a garage band four years ago and regret not trying it out. What an awesome and weird machine
      The name's Max; Bond Max

    10. #10
      ajfclark's Avatar
      ajfclark is offline
      is probably slacking off from
      studying
       
      Happy
       

      Join Date
      Mar 2017
      State
      Victoria
      Posts
      1,916
      Mentioned
      42 Post(s)
      Quoted
      672 Post(s)
      Australia

      Quote Originally Posted by maxi View Post
      Exciting - following this. I got offered a garage band four years ago and regret not trying it out. What an awesome and weird machine
      The music is great, and somewhat surprisingly the stereo is actually noticeable.

    Page 1 of 3 123 LastLast

    Thread Information

    Users Browsing this Thread

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

    Tags for this Thread

    Posting Permissions

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