exploring the 1973 Japanese arcades in this tweet...

I saw this tweet that features two old photos of Japanese arcades that had been colourized via AI.

https://twitter.com/onionsoftware/status/1351516597840580609

Let's spot some games!

"American Game"!
we can identify three machines here, can you?

introducing... サーカス (Circus)

It's here and it's awesome.  I'm so happy to say I finally have a Japanese 10¥ machine in my collection!  Yes, it's Circus aka サーカス from Taiyo Sangyo in 1978.

When I got into Smart Ball (スマートボール) I started also discovering the world of 1970s Japanese 10¥ arcade machines.  These were games that you'd find in candy shops and would dispense tokens that could be exchanged for sweets or prizes.

It seems like lots of them did not survive.  Many were operated outdoors at the front of shops.  Sometimes under an awning, sometimes not.  Just lined up front along with vending machines.  Japan's a relatively small island with lots of coastline, so atmospheric conditions in many parts were probably not conducive to long-term preservation.

But what's really special about this one is that it is "New Old Stock".  It seems like a small number of Circus machines (and a game called Home Run Fever) popped up on Yahoo Japan Auctions.  Here was a chance to own a nearly brand-new 10¥ game from the 1970s, probably the only chance I'll ever have to get one in this condition too.

10¥ arcade machines do come up on occasion, but very rarely, they're often in quite poor condition, and they sell for hefty sums of money.

Enough preamble, let's open it up and take a look!

math: Mills slot machine

Who doesn't love finite mathematics?  so practical, so alluring!  And awesome for gambling analysis!

I found this site that sells slot machine reels and eventually found the reels that are on my Mills Hightop.  It was on a picture that had 8 reels, but I was able to find the specific ones for me.

Here is an edited pic, and as you can see they are out of order but I drew numbers along the bottom

excuse the ordering difference

There are 20 symbols on each reel, and here is the number of occurrences:

and here are the odds of each of those coming up on each reel:

here are the outcome scenarios:

When doing this math it's important to note the NET win.  A single cherry pays two coins, but since you spent 1 coin for the spin, your net win is only 1.

The triplets (oranges / plums / bells) can also be finished by a BAR on the third reel, which adds an additional 5% chance for the winning symbol to appear on the third reel.

Interesting to note how bells are plentiful (7 of them) on the 2nd reel and 3rd reel, but on the first reel there is just a single one.

Oranges and plums only have 2 symbols each on the 2nd reel.

the third reel introduces the Lemon symbol, which is just there to mess up your triples.  (you can still win with a lemon in the third reel, if there are cherries too)

3 bars nets you a 20 coin payout plus the jackpot.  I'm told the jackpot is traditionally loaded with 80 coins, making the full payout 100.

So what is that final # in the bottom right?  That is the Expected Value of your spin.
Play 1 coin, expected to lose 0.1635 coins.  
The machine is expected to pay out 0.8365, or 83.65% of the input value.

This is an important number because the lower it gets, the less "exciting" the machine is for the player.  It just becomes a place to dump your money.  If it's too high, it cuts into the operator's profit.

These days casinos control this expected result digitally.  You can see it easily if you get a pachislo machine, do the reset, and you can change the odds there to be even more generous.  But that's boring.  I find it really interesting on mechanical machines though because they had to have this math in mind during the design.

The reels themselves can be changed!  It's not a matter of just putting on a new sticker though, as the reel has to have the physical holes that align with the symbols.  Here is an example of someone physically altering a reel to reduce the odds and increase the profit.

What happens if the jackpot hopper is empty?  If we reduce the Jackpot payout from 100 to 20 (the internal payout online) then the expected losings go from 0.1635/coin to 0.2035.
The expected payout goes from 83.65% to 79.65%

introducing... a 1948 Mills High-top slot machine

New arrival!   a Mills high-top slot machine from around 1940

If you appreciate purely mechanical devices, you absolutely need to get a mechanical slot machine.  What a wonderous piece of engineering.

exploring the arcade in 東京流れ者 aka Tōkyō nagaremono aka Tokyo Drifter (1966)

 OK, a quick one...

3 different promo posters/covers for 東京流れ者 / Tokyo Drifter (1966)

shall we enter?

exploring the arcade in Android Kikaider (1972)

It's Kikiader time!    Another clip passed my way by James at Pinballspotting.  Jump to 6:54 in the clip for the arcade.  This episode came out July 29, 1972 and is called 呪いオレンジアントの死の挑戦, aka Noroi Orenji Anto no Shino Chōsen, aka The Accursed Orange Ant's Deadly Challenge.

"hey let's go into this awesome arcade!"

Japanese reggae: Boogie Man doing Pachinco Man!

Boogie Man ‎– Pachinco★Man

and oh shit someone did a jungle remix!

https://soundcloud.com/dove6/king-of-the-pachinco-man

but of course since he's a Japanese reggae performer, requisite to post this: