# Episode 91 - The Reflex

**Source:** For Amusement Only EM and Bingo Pinball Podcast  
**Type:** podcast_episode  
**Published:** 2015-06-10  
**Duration:** 13m 23s  
**Beat:** Pinball

**URL:** https://foramusementonly.libsyn.com/episode-91-the-reflex

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## Analysis

Nick Baldridge provides a comprehensive technical and historical overview of the reflex unit, an automatic proportioning circuit used in bingo and horse racing pinball machines to adjust odds and feature availability based on gameplay. The reflex unit was a closely guarded trade secret that remained undocumented on schematics until Bally's transition to 20-hole games in the 1970s, likely related to the company's efforts to distance itself from gambling associations after becoming publicly traded. Operators could adjust reflex behavior through Jones plug configurations, gear swaps, and various modifications, though many lacked understanding of the mechanism's purpose and function.

### Key Claims

- [HIGH] The reflex unit was an automatic proportioning circuit that stepped down with each coin/play and stepped up with wins, making machines progressively tighter as players won. — _Nick Baldridge explaining core reflex mechanics, drawing from his research and experience with EM bingo machines_
- [HIGH] The reflex unit was not documented on schematics and remained a trade secret from its invention in horse racing games in the 1940s through the 1960s magic screen games. — _Nick Baldridge on reflex documentation history and secrecy practices_
- [HIGH] Bally suddenly began documenting the reflex unit on schematics when they switched to creating 20-hole games. — _Nick Baldridge on the shift in documentation practices during a specific product transition_
- [MEDIUM] Bally's decision to document the reflex may have been connected to the company becoming publicly traded and wanting to distance itself from gambling associations. — _Nick Baldridge acknowledges this is speculation based on what he 'heard' and cannot confirm_
- [HIGH] Phil Hooper has produced the first comprehensive documentation on how the reflex unit works and how to adjust it for permissiveness or tightness. — _Nick Baldridge crediting Phil Hooper for detailed technical write-up on reflex operation_
- [HIGH] United also had a reflex unit and competed fiercely with Bally in bingo machine development. — _Nick Baldridge referencing his previous overview episode on United versus Bally competition_
- [HIGH] In the 1970s, a Jones plug adjustment (four wires, 6 or 8 pin female connector) was introduced to allow operators to adjust reflex permissiveness without internal modifications. — _Nick Baldridge describing the Jones plug reflex adjustment mechanism_
- [MEDIUM] Some operators would drill bolts or screws through the reflex unit to prevent it from stepping down, effectively locking it at maximum permissiveness. — _Nick Baldridge has not personally encountered this modification but has seen pictures of it online_

### Notable Quotes

> "The worst time to play a bingo is right after someone has won a bunch of credits on it. If you walk up and start trying to play, you will end up spending much more money in order to achieve the same effect."
> — **Nick Baldridge**, ~3:45
> _Explains the practical player experience consequence of reflex mechanics — demonstrates how the system affected casual players' economics_

> "This is why Phil Bogan's strategy of only playing a few coins and starting with even the lowest odds, where you have your greatest chance of recouping your cost, is wise."
> — **Nick Baldridge**, ~4:30
> _Attributes specific play strategy to understanding reflex unit behavior; shows expert player adaptation_

> "The reflex unit was what amounted to a trade secret. The reflex unit was not documented and it was not put on the schematics. This persisted for years and years and years."
> — **Nick Baldridge**, ~5:15
> _Core claim about the secretive nature and undocumented status of reflex technology across decades_

> "I heard that as Bally became a publicly traded company they wanted to distance themselves a bit from their gambling image, and so they started making the games a little friendlier."
> — **Nick Baldridge**, ~6:45
> _Speculative theory about business/regulatory context for documentation shift; explicitly marked as unverified_

> "These reflex gears are probably about two inches in diameter... There were several different gears that were shipped with each machine and the operator could swap them out."
> — **Nick Baldridge**, ~11:30
> _Describes operator-accessible tuning hardware; invites community correction on specifications_

> "The machines would be shipped with extra reflex gears... the operator could swap them out... to get the optimal ratio of step up versus step down. The operators wanted it to step up faster in order to take more money."
> — **Nick Baldridge**, ~12:00
> _Clarifies operator motivations and economic incentives in reflex tuning practices_

> "For the most part, collectors like to make it as loose as possible... I prefer to have mine operating as it came to me."
> — **Nick Baldridge**, ~20:30
> _Explicit statement of collector philosophy divide; reveals the speaker's own preservationist approach to reflex units_

> "The reflex is in charge of finding treasure in the dark. And watching over Lucky Clover isn't that bizarre. Every little thing the reflex does leaves you answered with a question mark."
> — **Nick Baldridge (quoting Duran Duran's 'The Reflex')**, ~25:00
> _Creative cultural parallel drawing — uses pop music lyrics to metaphorically summarize reflex unit mystery and function_

### Entities

| Name | Type | Context |
|------|------|---------|
| Nick Baldridge | person | Host and primary speaker; expert EM/bingo pinball researcher and collector with deep technical knowledge of reflex units and bingo machine mechanics |
| Phil Hooper | person | EM pinball researcher credited with producing the first comprehensive technical documentation on reflex unit operation and adjustment |
| Phil Bogan | person | Bingo pinball player whose strategy of playing few coins at lowest odds is cited as optimal play method given reflex unit behavior |
| Bally | company | Major historical bingo and pinball machine manufacturer; developed and refined reflex unit technology, later became publicly traded and began documenting reflex in schematics |
| United | company | Competitor to Bally in bingo machine market; also developed and used reflex unit technology in their machines |
| Vic Camp | person | EM pinball industry figure interviewed on podcast; provided anecdotes about New Jersey bingo machine operators and long-term route placements |
| For Amusement Only Podcast | organization | EM and bingo pinball podcast series hosted by Nick Baldridge, covering technical, historical, and gameplay aspects of electromechanical pinball |
| reflex unit | product | Automatic proportioning circuit mechanism in bingo and horse racing pinball machines that adjusts odds and feature availability based on gameplay and coin input |
| Jones plug | product | Electrical connector (6 or 8 pin female) introduced in 1970s as operator-accessible reflex adjustment mechanism |
| horse racing games | product | Early pinball machine category from 1940s where reflex unit was originally invented |
| magic screen games | product | Bally bingo machine category from 1960s that still used undocumented reflex units |
| 20-hole games | product | Bally game format introduced in 1970s alongside which reflex units began appearing on schematics |
| Duran Duran | person | 1980s pop band whose song 'The Reflex' is used metaphorically to illustrate reflex unit mystery and function |

### Topics

- **Primary:** reflex unit mechanics and function, bingo machine history and development, operator knowledge and machine tuning practices, trade secrets and documentation gaps in pinball history
- **Secondary:** collector philosophy on machine preservation vs. modification, Bally's business transitions and public company status, competition between Bally and United
- **Mentioned:** player strategy adaptation to machine behavior

### Sentiment

**Neutral** (0.55) — Speaker maintains educational, informative tone throughout. Shows enthusiasm for the technical complexity and historical mystery of the reflex unit. Appreciates the engineering ingenuity ('it's pretty fascinating how they thought of this back in the 40s'). No criticism of manufacturers or negative sentiment toward machines or mechanics. Acknowledges speculation vs. confirmed facts, maintaining appropriate epistemic humility.

### Signals

- **[historical_signal]** The reflex unit remained an undocumented trade secret from the 1940s through the 1960s, only appearing on schematics when Bally transitioned to 20-hole games in the 1970s. (confidence: high) — Nick Baldridge: 'The reflex unit was what amounted to a trade secret. The reflex unit was not documented and it was not put on the schematics. This persisted for years and years and years.' He cites this persisting 'from the reflex's invention with the horse racing games in the 1940s up through the 60s and the magic screen games.'
- **[business_signal]** Bally's decision to document the reflex unit on schematics may have been motivated by the company's transition to public company status and desire to distance itself from gambling associations. (confidence: medium) — Nick Baldridge: 'I heard that as Bally became a publicly traded company they wanted to distance themselves a bit from their gambling image. And so they started making the games a little friendlier.' He explicitly notes 'I don't know anything but I heard' and 'of course I can confirm anything,' marking this as speculation.
- **[restoration_signal]** Operators developed multiple methods to modify reflex unit behavior, including gear swaps, Jones plug adjustments, gaff bolts, and destructive modifications like drilling through the unit. (confidence: high) — Nick Baldridge: 'The operators would sometimes drive a bolt or a screw through the reflex unit itself, which would prevent the unit from stepping down.' Also describes gear swaps, Jones plug configurations, and resetting reflex to permissive position.
- **[product_concern]** Drilling modifications through sealed reflex units to lock them created difficult-to-reverse damage risks, including broken fingers, damaged rivets, and wiring harm. (confidence: medium) — Nick Baldridge: 'It does not look fun to reverse. You back out the screw or bolt and then hope that it didn't damage the fingers of the unit or drill through any rivets or any of the wiring behind the disc.'
- **[collector_signal]** Collector community divides between those who modify reflex units to maximum permissiveness and preservationists like the speaker who maintain original specifications. (confidence: high) — Nick Baldridge: 'For the most part, collectors like to make it as loose as possible... I prefer to have mine operating as it came to me... I have not swapped them in because I like to have the machines running as they were when they were en route.'
- **[content_signal]** For Amusement Only Episode 91 delivers first comprehensive podcast deep-dive into reflex unit mechanics, history, and operator practices, filling a knowledge gap in community media. (confidence: high) — This is the dedicated episode focus; prior episodes referenced 'United versus Bally' overview and Vic Camp interview, showing serial topical coverage.
- **[design_innovation]** The reflex unit represents a sophisticated automatic proportioning circuit design from the 1940s that adjusted game odds dynamically based on player wins and coin input, predating electronic game balance systems by decades. (confidence: high) — Nick Baldridge: 'The reflex was essentially an auto portioning circuit... Each time that you put in a coin, the reflex unit would step down and when you won, the reflex unit would step up.' Notes it was invented in horse racing games in 1940s.
- **[operational_signal]** Operators were financially incentivized to modify reflex units to step up faster and step down slower, directly contrary to player interests and machine fairness. (confidence: high) — Nick Baldridge: 'The operators wanted it to step up faster in order to take more money. Most operators wouldn't want it to step down at a one-to-one ratio.'
- **[community_signal]** Phil Hooper's recent technical documentation represents a community effort to consolidate and document previously secret bingo machine technology, democratizing knowledge that was intentionally obscured for decades. (confidence: high) — Nick Baldridge: 'Phil Hooper has done an excellent write-up on how the reflex unit works, how to make it more permissive, or how to tighten it up.' Credited as first comprehensive documentation.
- **[historical_signal]** The reflex unit remained mysterious not only to players but to many operators as well, creating information asymmetry that benefited manufacturers and knowledgeable operators. (confidence: high) — Nick Baldridge: 'The reflex unit was a mystery to operators as well... the machine would take more button presses over time, and that's 100% due to this reflex unit' [but operators didn't understand why].
- **[gameplay_signal]** Reflex units created dynamic difficulty increase during play sessions: machines became progressively tighter as players won, forcing higher coin/button investment for the same outcomes, embodying a proto-rubber-banding difficulty system. (confidence: high) — Nick Baldridge: 'As you won, as you racked up the replays on the machine, the machine started to clamp down, and it was less and less likely to grant you those. You had to put in more and more money or push the button more and more times.'

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## Transcript

 what's that sound it's for amusement only the em and bingo pinball podcast welcome back to for amusement only this is Nicholas Baldridge it's here it's here it's finally here the episode about the reflex unit so as i've mentioned in previous podcasts over and over again the reflex was essentially an auto portioning circuit that would engage as you won or as you played coins on a bingo. Each time that you put in a coin, the reflex unit would step down and when you won, the reflex unit would step up. Now in the reflex's default position with as many pins active on the rivets on the disk, it would make the machine more giving. So each time you pushed a button or put in a coin, you were more likely to connect the necessary circuitry in order to grant you a feature or an odds jump or, you know, the thing that you were playing for. So, as you won, as you racked up the replays on the machine, the machine started to clamp down, and it was less and less likely to grant you those. You had to put in more and more money or push the button more and more times in order to get the same features and odds jumps. the worst time to play a bingo is right after someone has won a bunch of credits on it. If you walk up and start trying to play, you will end up spending much more money in order to achieve the same effect. This is why Phil Bogan's strategy of only playing a few coins and starting with even the lowest odds, where you have your greatest chance of recouping your cost, is wise. The other thing to note about the reflex is that it was what amounted to a trade secret. the reflex unit was not documented and it was not put on the schematics. This persisted for years and years and years starting from the reflex's invention with the horse racing games in the 1940s up through the 60s and the magic screen games. now when Bally switched to creating the 20 hole games the reflex unit suddenly started appearing on the schematics and it's a really interesting thought process that must have happened now I read some stuff at this time and of course I can confirm anything because I don know anything but I heard that as Bally became a publicly traded company they wanted to distance themselves a bit from their gambling image. and so they started making the games a little friendlier I guess you'd say and this is one way that perhaps they did this because the reflex unit was a mystery to operators as well and I'll get back to that point in a minute but as a player something that I've heard before is that the machine would take more button presses over time, and that's 100% due to this reflex unit. Now, United also had a reflex unit, and as I mentioned in my brief overview of United versus Bally, they were in stiff, stiff competition trying to one-up each other with these bingo machines. And as I've also mentioned before, these bingos earned big money. They were a big deal. So both Bally and United sold an awful lot of them, and they earned a lot for the operators. If you listen to the Vic Camp interview, you'll hear that in New Jersey, there were essentially the same group of machines maintained for years and years and years without being switched out. Well, those machines are racking in the money. It's just incredible to think about. But, getting back to the reflex. In the 1970s, they started putting in a reflex adjustment. This reflex adjustment was a Jones plug, which was comprised of four different wires. The idea being, it would mate into a 6 or 8 pin female Jones plug. Now, this 6 or 8 pin female Jones plug would only have two or four wires attached. And so you would want to connect the most wires in order to make the reflex as permissive as possible. What this would do is it would allow the reflex to step down faster with that adjustment than it would if you had none of the wires connected. So, the reflex is also interesting because the machines would be shipped with extra reflex gears. These reflex gears are probably about two inches in diameter. I'm sure someone will correct me. Maybe they're two and a half or three. Well, at any rate, there were several different gears that were shipped with each machine and the operator could swap them out Now there were operators that were in the know as to what these things were and again I come back to that in just a second but they would swap out the gear to get the optimal ratio of step up versus step down The operators wanted it to step up faster in order to take more money. Most operators wouldn't want it to step down at a one-to-one ratio. So, the gears were another way that they could be adjusted. Now, some operators, when they took the unit apart, this is a mostly sealed unit, by the way. It's not something that you can access, even, because the unit is entirely enclosed. You can look in the side and see the gear and where it mates to another gear, but you can't actually look in and see the disc and the fingers or the wipers that are making contact on the rivets. It's pretty fascinating when you think about it because this is all kind of hush-hush secret stuff. But the operators would sometimes drive a bolt or a screw through the reflex unit itself, which would prevent the unit from stepping down. I've never had a game that had this modification done, but I've certainly seen horrible pictures online of games where this has happened. and it does not look fun to reverse. You back out the screw or bolt and then hope that it didn't damage the fingers of the unit or drill through any rivets or any of the wiring behind the disc. It's kind of interesting. So, again, the reflex unit being such a secret is pretty fascinating to me because it wasn't documented until very recently. Phil Hooper has done an excellent write-up on how the reflex unit works, how to make it more permissive, or how to tighten it up. For the most part, collectors like to make it as loose as possible. And there are several ways to do this. One is to reset the reflex into its normal position and then cut the power to the coils. That's kind of a heavy-handed approach. Another would be to use the gaff bolt, if it's got it, to limit how much the machine allows the reflex to step up. is a built-in adjustment that prevents the stepping, not a drilled modification. But here's my take on the Reflex, and here's what I like about it. It provides yet another dimension to bingo gameplay for me I prefer to have mine operating as it came to me So I do have a couple extra reflex gears but I have not swapped them in because I like to have the machines running as they were when they were en route, preferably, just with all the features repaired if they've been cut. But as far as the reflex goes, I prefer to have that working as it came to me. So that means whatever the ratio of step up to step down, I leave it alone. I just make sure that the reflex is actually working, and it's stepping up appropriately when you win, and it's stepping down appropriately when you coin, and then I'm good. so I should mention when I say coin I mean either physically putting a coin in the machine or actually playing credits that you've won you don't have to put in money in order to make the machine step it down you're just playing money but if you were to turn the machine off and back on which would be if you got paid out, then the reflex would remain at whatever position it was at. Having the replay reset run does not step down the reflex unit. So, another interesting thing to note about reflex units is some games have more than one. Depending on the features involved and the way that those features paid out in credits, There may be a secondary reflex unit, which controls the overall tightness of the game in combination with the other reflex unit. It's pretty fascinating how they thought of this back in the 40s. so to leave you for tonight I thought I would discuss how the Duran Duran song The Reflex actually has a lot in common with the Reflex units found in these bingos and the horse race games the last verse is oh the Reflex what a game He's hiding all the cards. The reflex is in charge of finding treasure in the dark. And watching over Lucky Clover isn't that bizarre. Every little thing the reflex does leaves you answered with a question mark. Fairly interesting. Gives a whole new meaning to that song, doesn't it? Well, thank you again for listening. My name again is Nick Baldrige. You can reach me at foramusementonlypodcast at gmail.com. And you can listen to us on iTunes, Stitcher, Pocket Casts via RSS, on Facebook at For Amusement Only Podcast, on Twitter at Bingo Podcast, and on our website, which is foramusementonly.libsyn.com. Thanks very much for listening, and I'll talk to you next time.

_(Acquisition: groq_whisper, Enrichment: v3)_

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*Exported from Journalist Tool on 2026-04-13 | Item ID: 0086b295-67dd-4283-934d-0bb213d71bf4*