The Internet Pinball Serial Number Database or IPSND collects serial numbers of pinball machines and publishes a database of these on the Internet. Our goal is to make available a registration of all pinball machines in existence and allow tools for slicing, dicing and visualization of the data.

Games: 6,703  Serials: 69,580  Visitors: 78,310,058  Members: 5,721  Photos: 45,038  Lat/Lng: 38,405  Masks: 69,580(1,038.04%)  Traits: 571  Nudges: 228,405  Backglasses: 1,865
  Most Serials: Twilight Zone(1,333)  Most Submissions: Dennis Braun(6,141)  Most Points: Dennis Braun(45,700)  Highest Quality: The Knight(17.00)  Most Nudges: pinballservice-nl(29,105)
Black Knight - IPSND/IPDB No. 310 - November 1980
Backglass Image
Manufacturer: Williams Electronics, Inc. (1967-1985)
Players: 4
MPU: Williams System 7
Production Run: 13,075
Game Type: Solid State Electronic (SS)
Model: 500
Submissions: 440 serials of 13,075 (3.37%)
Coverage help:

Coverage is a mathematical interpretation of the serial numbers that have been submitted so far. The term 'coverage' relates to the amount of the production run that has been 'covered' in the given submissions.

There are two coverage methods shown, each has a different approach of calculating an guess on the number of games produced by analysing the currently submitted serial numbers.

Linear: Linear coverage simply looks at the highest serial number and subtracts from it the smallest serial number to estimate the number of games produced. For some games, this works fine because the serial numbers were sequential and without gaps (Early Bally, Early Stern, etc). However, this approach starts to fail quickly for games that serial numbers are part of a bigger numbering scheme (Williams pre 1984, Current Stern) or that intentially had gaps/skips in the numbering sequence(Gottlieb post 1960). If you see a linear coverage number that is higher than the known production run, it is probably not the best way to look at the serial range and you should look at the clustered approach below.

Clustered: Clustered coverage assumes that there are gaps/skips in the serial sequence for a game. It groups the serial numbers together based upon how close they are to the next serial number in the sequence. If they fall within a certain threshold then the SerialBot assumes that there are valid serial numbers between the two. If they are far enough apart, then the SerialBot assumes this is a gap. Once all the gaps and groups are determined, it sums up all the linear ranges in each group. This way, if a sample run of games started at 15,000-15,100 and the production games started at 17,000 onwards, it would assume that the serial numbers between 15,100-17,000 were a gap an are not counted. Using this method, as more serial numbers are submitted the gap analysis will get more accurate.

67,461 (515.95%) linear / 13,586(103.91%) in 15 clusters 653 wide.
Cluster Serial Number SerialBot Submitted By Country Game Part

Submit a new Game Trait

The following traits help

Game Traits are properties for an individual game that you would like to see tracked along with the other information gathered for a serial number submission. Some examples of existing traits are... Joust: Black or Blue bottom Arch, Black Knight: Faceted Inserts or Normal Inserts, Twilight Zone: 3rd Magnet Installed or not.

have been submitted for this game...

Field NameDescriptonSubmitted BySubmit DateSubmitted
Has Faceted Inserts Most games had special faceted inserts. According to Steve Richie the game designer... "Black Knight was the first game ever to employ faceted inserts (the transparent inlaid plastic windows) in the playfield. My design was a simple eight-sided "Jewel Look", but insert texturing progressed from there to many different designs, finally settling on refracting radial lines originating at the center of round and rectangular inserts and from points of arrows and lightning bolts, etc." Reproduction playfields do not have faceted inserts as described but instead have the more common 'starburst' inserts which have radially emanating lines. Jess Askey2/17/2007226
System 7 Power Supply. Black Knight used two diferent power supplies, the System 6 version with the transformer in the head, and the system 7 version with the transformer in the cabinet. Mike Goss8/16/2007224
CPU DIP SWITCHES Some early Sys 7 games had CPU/MPU boards with 2 x DIP switches, 2 x Diagnostic switches and 2 x LEDs extra to the 7 segment displays. I'm interested if this was the early BK games with Transformer in the backbox. Richard Harvey7/3/2009145
SBA Coin Mech Some have the Susan B. Anthony Coin Mech installed in the center coin location with the yellow "Dollars" insert. Jim May12/28/2009205
Multiball lamp insert The majority of games used red arrowhead inserts for multiball lamp. However, some very early machines apparently used green inserts here. Hans Haase5/25/2010173
Multiball Plastic Protector Some games had a steel plate installed under the plastic that covers the multiball trough in order to protect that plastic from breaking. Hans Haase5/25/2010151
Ball trough microswitches Due to quality control issues with incorrectly manufactured leaf switches, Williams produced a retrofit set that converted the lower ball trough and multiball lock trough to use microswitches instead of leaf switches. Hans Haase5/25/2010137
Drop Bank Rebound Switches The original playfield design had a switch behind three of the four banks of drop targets (there was no room for this in the upper left drop bank). When the targets were down, the ball would hit the rebound rubber behind the targets and thus hit this switch. The switch was removed because it was not hit much. The timers would reset the drop target banks, so these switches weren't exposed often enough to justify the cost of keeping them. Three images are presented here of the center drop target bank, as an example. The left image is the flyer game, and a blue circle has been drawn around this switch. When games did not have this switch, the playfield might still have the cut out for it (center image). Your game may not even have the cut out (right image).(Valid Values: Switches present,Cutouts only, no switches,No switches, no cutouts)
Jay St@fford4/22/2014107
Cabinet Bottom Material Games seemed to have been manufactured with different materials on the bottom of the cabinet. This may have been due to Williams using two different cabinet companies because Black Knight was such a hot seller.(Valid Values: Plywood,Masonite (smooth))
Lenny Esposito6/8/202262

Cluster Serial Number Country

This section lists any known game part serials that happen to match this game's serial mask (if defined). What this can tell you is if a game has any orphaned parts that might exist in other machines. This generally applies to CPU/MPU boards, Driver Boards, Display boards etc that are easily moved from game to game. Repair shops and distributors often robbed parts from other 'scrap' games laying around in a pinch if they were not able to fix the original part or of the original part was damaged beyond repair. If serials start showing up in the database as 'game parts', there is potentially a good chance that that game has been parted out completely, which is unfortunate. It is becoming more and more common for people to part out games and sell them on ebay simply because the seller can often make more money that way.... Please do not sacrifice complete games for money!!!

SerialBotSerial NumberTypeSubmitted ByCountryDetails
20461 455261 MPU/CPU John Vorwerk United States flag United States
24729 455290 Display/Driver John Vorwerk United States flag United States
12149 455300 MPU/CPU Jess Askey United States flag United States
28987 455364 MPU/CPU John Vorwerk United States flag United States
31242 456001 Sound Board Antti Peltonen Hungary flag Hungary
33804 456116 Solenoid Driver Antti Peltonen Finland flag Finland
30926 456890 Power Supply Antti Peltonen Finland flag Finland
28239 460175 Display/Driver John Vorwerk United States flag United States
36064 460220 Power Supply Adam United States flag United States
37823 460764 Display/Driver John Vorwerk United States flag United States
31418 460764 MPU/CPU John Vorwerk United States flag United States
26339 460939 Display/Driver John Vorwerk United States flag United States
29463 461325 Sound Board John Vorwerk United States flag United States
35247 461375 MPU/CPU John Vorwerk United States flag United States
28153 461412 MPU/CPU John Vorwerk United States flag United States
21979 461729 Sound Board John Vorwerk United States flag United States
21435 461977 Display/Driver John Vorwerk United States flag United States
23796 462013 Sound Board John Vorwerk United States flag United States
30772 462230 Sound Board John Vorwerk United States flag United States
28401 462272 Power Supply Jess Askey United States flag United States
26437 462272 Power Supply John Vorwerk United States flag United States
21436 462389 Display/Driver John Vorwerk United States flag United States
34661 462398 Power Supply John Vorwerk United States flag United States
34926 462673 Display/Driver John Vorwerk United States flag United States
54636 462908 MPU/CPU Fun House Korea, Democratic People's Republic of flag Korea, Democratic People's Republic of
20459 463174 Display/Driver John Vorwerk United States flag United States
31002 463404 MPU/CPU John Vorwerk United States flag United States
35331 463675 MPU/CPU John Vorwerk United States flag United States
35249 463693 MPU/CPU John Vorwerk United States flag United States
8690 463702 Display/Driver Jess Askey United States flag United States
25669 464380 MPU/CPU Antti Peltonen Finland flag Finland
25890 464521 Display/Driver Antti Peltonen Finland flag Finland
34913 464533 Sound Board John Vorwerk United States flag United States
36407 464601 Sound Board John Vorwerk United States flag United States
27458 464724 Display/Driver John Vorwerk United States flag United States
31569 464903 Display/Driver Rod McLarge United States flag United States
20963 465432 MPU/CPU John Vorwerk United States flag United States
23599 465724 Sound Board John Vorwerk United States flag United States
20962 477514 MPU/CPU John Vorwerk United States flag United States
25649 478300 Sound Board Robin Leath United Kingdom flag United Kingdom
24042 479089 Display/Driver John Vorwerk United States flag United States
21437 479163 Sound Board John Vorwerk United States flag United States
21978 479407 Sound Board John Vorwerk United States flag United States

This section lists any known information about how to physically find serial numbers on games created by this manufacturer. For all manufacturer tips, please visit the Serial Tips Page . (Please do not post serial numbers here on this form.)

Posted 1/11/2007 11:52:51 PM by Bill Ung

Older Williams games are very much like older Gottlieb games. The serial numbers are stamped/etched into the wood on the front of the cabinet. This holds true for anything prior to say, oh, 1984/1985, or around System 9. Occasionally you have to look hard for it, like the Joust game at PAPA 5. I did find it eventually, serial number for that game was: 624985. Williams games from the late 60's up to the mid 80's were 6 digit numbers.

Posted 6/9/2007 8:07:09 PM by Jess Askey
Also, for Joust and Rat Race games... the serial for the tabletop style cabinet is on the 1st player side in the bottom left . It is a 6-digit number stamped into the wood.
Posted 6/19/2007 12:37:14 PM by Jess Askey
Williams also seemed to staple small rectangular paper labels inside the cabinet were the backbox attaches that has the serial number nicely printed in clearly legible text. You have to take the backbox off to see this area generally but it is an easy way to read a serial number if the stamp is mangled. There is also a stamp in this same location generally. I have a hyperball cabinet that has a clearly stamped serial number on the front of the cabinet and inside the top area that doesn't match the printed label however, so it seems they must not have paid close attention to the paper and stamps serials matching all the time.
Posted 6/25/2007 11:10:53 AM by Jess Askey
For Williams video games, the serial number is stamped in the front of the cabinet below the control panel. It is typically above the coin door to the right.
Posted 11/8/2007 6:51:33 PM by Jess Askey
On my Time Fantasy, there was a paper tag stapled on the underside of the Playfield with a serial number on it. The paper tag was about 1" by 2" and had the game name in Black with the serial number printed in Red.
Posted 4/7/2011 8:22:33 PM by Mark Skotchdopole
Found mine on paper tag...90910. interesting because my backglass is green. The guy who owns 90909 is blue. Could mine be the first green backglass made?
Posted 9/17/2011 9:18:09 PM by David DiEnno
Williams Gold Rush: The serial number is located in several places. Inside the lightbox, inside the lower cabinet, the upper playfield apron...all of these three are paper tags. They should all match. If not, sometime in the machine's service life, a part was replaced.
Posted 11/14/2011 8:40:51 AM by Pistol Pete
The serial number may also be found stamped into the metal sheet in the backbox near the right mounting bolt hole, front edge of the metal sheet
Posted 1/8/2012 6:09:04 AM by Crimson Clyde
Let´s see what I found on my Williams Big Deal System. There are two identical numbers I found after a long search. 1st: On the front of the cabinet right under the coin door stamped into the wood. 2nd: Inside the cabinet, viewed through the coin door with a lamp on the right side of the wood crossbrace, printed on a label with the words "Cabinets". These two # are identical! I found many more numbers inside the cabinet but I think that the one stamped in the wood is the true serial. The label with "Cabinets" on it is the only one which matches the one in the wood. So finally you have a double chance to find it. There's also a label called "Panel" inside the cabinet. This label really looks like that one with "Cabinets", but the number isn't the same with "Cabinets" and that in front of the Pinball system. So now, I have to find the year of construction...
Posted 2/10/2012 1:05:38 PM by Robin Leath
If you are struggling to read the stamped Serial No. on the front of the cabinat (Williams somewhere below and to left of coin door) try doing a rubbing by placing a piece of paper over it and rubbing a pencil so that the lead is flat to the paper. Rub this back and forth and the Serial No. will appear and make it easier for you to read. I had to do this on my Gorgar as the No. was in the black area and not heavily stamped, but became clearly visible on a rubbing !
Members can submit new tips on how to find serial numbers! Sign up for a free membership here!

This game has the following serial number formats defined in the database. As serial numbers are sumbitted, trends are recognized and defined or information about a serial number format is collected through historical information.

Production Game 452909, 455401, 455477 ^(?<sortdata>[0-9][0-9][0-9][0-9][0-9][0-9])$ False

The Serial Bot Summary information here gives a detailed explanation of the Serial Bot analysis for this specific game. The theory behind the Serial Bot is this...

Every game has many many serial number submissions, the goal of the IPSND is not to guarantee that *all* information is 100% correct but that over time, the system should automatically devalue inaccurate submissions while increasing the value of correct submissions.

You may click on the SerialBot score of any submission to see how it was calculated.

SerialBot Color Codes:
- Not Validated The serial number submission has not yet been validated by the submitter via email.
- Unknown There is no known information on the serial number format for this game yet. As more submissions are received we can start to make a best guess on the serial number format.
- Good If a serial does not fail any of the tests for a status of Warning or Bad, then it is good.
- Suspect A serial will have a suspect status if the format is technically correct but there is something wrong with the data. Examples might be that the number might be too high or low for the known range of serials for this game.
- Bad If a game has a serial number definition mask defined for it, then a serial may be marked as 'bad' if the number does not validate agains the mask. Masks are created for games by looking at known serial number formats and consist of a regular expression to define the format of a game serial.

SerialBot Scores:
1 Point Awarded if the serial number has a game assigned to it. This autoatically makes submissions with a known game more valuable than submissions without a known game.
1 Point Awarded if the serial number has been 'verified' by the submitter. A submission is 'verifed' if the submitter clicks on the link in the email sent to them for each submission. The basis for this rule is that submissions by people that do not take the time to respond to the email might be entering garbage data and/or giving fake email addresses. However, it is common for 'verification' emails to get stuck in spam filters etc, so, members may have 'verification' emails re-sent at any time.
1 Point Awarded if the submitted serial number matches one of the predefined serial number masks for this game.
1 Point Awarded if the serial number was marked as 'Physically Viewed' during the submission process. This is an interesting distinction as there are many times that serial numbers are submitted off owners lists, Ebay auction, etc. While these serial numbers are valuable, they may also be innacurate. In comparison, Physically Viewed serial number submissions are numbers that the submitter has actually been in front of the machine reading the number and then submitting it. Since it is more likely to get a good visual from a physically viewed machine, this gains an extra point.
1 Point If a photo is uploaded with the serial number submission. The submission automatically gains an additional point. Be aware however that this opens the submission up to 'Nudges' by members where even more points can be added or subtracted based upon the quality and accuracy of the photo.
-3 to +3 Points Members can 'Nudge' every sumitted photo once and give it an extra boost of 1 point or take away 1 point depending if the photo matches the submitted serial number. While any number of members may nudge a serial, the nudging can only affect the score by +/- 3 points in either direction.

The following map shows the locations of all serial numbers that were submitted with a geolocation...