Copy of Seeburg Site Page  (no longer online)

Newassault page  (info mirrored from original)     

Jamma Pinout

Solder Side     Parts Side
+5v C 3 +5v
+5v D 4 +5v
-5v E 5 -5v
+12v F 6 +12V
coin counter #2 J 8 coin counter #1
lock out coil #2 K 9 lock out coil #1
speaker (-) L 10 speaker (+)
  M 11  
video green N 12 video red
video sync P 13 video blue 
service switch R 14 video gnd
tilt switch S 15 test switch
coin switch #2 T 16 coin switch #1
2p start U 17 1p start
2p up V 18 1p up
2p down W 19 1p down
2p left X 20 1p left
2p right Y 21 1p right
2p button 1 Z 22 1p button 1
2p button 2 a 23 1p button 2
2p button 3 b 24 1p button 3
  c 25  
  d 26  
GND e 27 GND
GND f 28 GND

The following image Courtesy of


freeplay adapter
To use this you just unplug the 8 pin plug in your jukebox and plug the above between the existing cable and socket.
Flip the switch one way and it's freeplay the other and it's normal operation.

constructed adapter

It can be built like this or put into a box.

This adapter circuit should work for all  M100A, M100B, M100BL, M100C, HF100G, HF100W, HF100R, HF100J, and HF100JL.
Unlike a version that is being sold on ebay this circuit will not release a single button press.
In other works if one key (letter or number) is pressed and a second is not the latch solenoid will remain on and not release.

It works by supplying a ground to the selector leaf switches which latches the selector solenoid. As long as the letter / number combo is completed the buttons will release and credit light will go off.

When time permits I will enhance this by adding a time out ct to disable the above if selection is not completed in a set time.
Which could be adjusted.

If anyone has the time and adds the time-out feature let me know, I'll include it here.

<>BTW a lot has been made about  a 1 key press not releasing and damaging the solenoid or worse. Suggesting a Child could press a single key and leave it that way. This should never really be an issue in your home.

Someone pointed out an ebay ad to me, showing a pre-constructed adapter, with the following statement

"Don't fall for that cheap adapter plug!  You can still burn out the solenoid with that cheap adapter.  Spend the extra $20.00 before you machine goes up in flames!!  Mine is ONLY safe way to protect your Seeburg!"

This is just a scare tactic, and very misleading.
If  you are handy and can build the adapter above it will work fine. If not, buying the marketed one  is an alternative

<>The damage the  seller is describing could  actually happen on normal coin operation without an adapter, and Seeburg designed their system so it could be left on for an extended period without damage.
Could the solenoid fail if left on for a day or days, sure.

However, as with all vintage electronics it is wise to connect them to a power strip, so when not in use they are not powered at all.
This eliminates any concerns for major failures when not in use.
So, the solenoid will NEVER be engaged for an extended period of time and NEVER fail because it got too hot.

Although not practical, ALL electronics should be on a power strip and turned off when not in use. Modern electronics, even when turned off are actually still on.
Some circuitry must stay on to power clocks and remote circuits. Often these more modern products use circuitry to eliminate the use of power transformers.
This leads to these products easily damaged when power surges occur.


Here is a simple circuit to help test a Seeburg Tormat System

        Assault Joystick Repair Info - As the name suggests
            Assault Stereo Speaker Upgrade - Add stereo sound!
            Atari Game Info  - (This site closed, this will take you to the archive, some links may no longer work)
            FAQ - Konami Pinout Class - As the name suggests  (archive)
            Arcade Central - Arcade game sounds , Flyers etc  (This site closed, for now it's linked here to the archive-be advised the archive will not have all content)
            HARDMVS  - restoring a NEO cabinet look here.
            Game Board Pinouts Archive -  (This site closed, for now it's linked here to the archive-be advised the archive will not have all content)
            Basement Arcade   - Great site, tons of info, including auction results and much more

           Mercury Amusement Co. - "Pinball information for collectors and homeowners"
           Phil's Arcade Links             (This site closed, for now it's linked here to the archive-be advised the archive will not have all content)
   - Usenet.<
           Switch Settings Archive - As the name suggests.
           Turaco - Edit game character sets.
 - Every one who is restoring a NEO cabinet should know this website. - Good place to get shockboxes, inserts, and NEO parts and games. - Very well know arcade company. This is where most of the street fighter and fighting game people get most of there Sanwa and semitsu joysticks and buttons. Customer service is excellent. This is the only place other then Happ where I order my joysticks and buttons from.

www.happcontrols. - Very well known arcade and redemption parts distributor. Majority of all the US made cabinets use Happ parts. - Well know website to order jamma harnesses, boards, adpaters, etc. They also make prewired MVS harnesses to replace your old one in your cabinet if its faulty. - Good place for your control panel overlays and graphics. - Good place to get custom or pre-cut plexiglass for your marquee or control panel.

Non Game Rekated Links of Interest

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