When setting the EOS switch gap you should do it by pushing the metal plunger into the coil, not by turning the crank - i.e. simulate the actual solenoid behavior. Otherwise your setting doesn't take into account any slack in the mechanism.

Awesome!! That’s what I wanted to hear, I’ll take another look this eve. I’ve never done via pushing the plunger in by hand, it makes sense

I’ve read 3.2mm gaps a couple of times which seemed excessive, especially compared to my other games.

Check that the flippers have float , up down through the nylon bushes
Don’t want them to bind

Cheers, yep, I’ve got my gap tool for that one

I would get rid of the Molex plugs. How often do you need to be removing flipper assemblies?

Also, if you think it may be the EOS switch, run an alligator jumper across the switch to see if power is increased. Just don't trap the ball or hold the flipper in too long, or else you will burn up the power winding.

Does anyone know where I can get the "tournament" ROM for Cheetah that allows 1 collect bonus per ball up the left side?

https://sites.google.com/site/allentownpinball/galaxy-asm/cheetah-mod.zip?attredirects=0&d=1

Thanks Scott!

What transformer are you using?

Great question.

I was thinking about the transformer yesterday. When I double flip, I'm getting a slight flicker on all lighting, looks like it could be a little under powered.

I'll take a look this arvo, I'd assume its the stock Quicksilver/MPU200 variety.

It should be say 16B-6 in white lettering on top.

So a cheetah just sold for $6500 in average condition with the green cabinet.

..............................what is the going price of the blue cab with the different color playfield inserts?

the question for Scott is can we get the tournament ROM using the proto blue Cheetah code? to get the better sound and the tourney bonus collect rule

Looks to be missing some letters, but doesn’t look to be 16B-6.

7565977D-A07D-481B-B1D6-7100BB5020DA (resized).jpeg

B98626BA-52EC-403B-94F1-8A48BBAA2C50 (resized).jpeg

BB91EBCF-D935-43D1-BD5E-B30FCF903878 (resized).jpeg

You have the smaller 16B-3 transformer. I can see the "3" stamped on top.

The larger -6 transformer measures 5.3 inches/ 134 mm across. The smaller -3 measures 4.5 inches/ 114 mm across.

As you now know, it will play with the -3 unit. But it will play better with the larger -6.

I thought you restored an original Quicksilver so the -6 should be there. However, two of the classic Sterns I bought had the smaller -3 transformer swapped into them; So anything can happen. Both played just OK. I put the larger -6 inside and the change in play action was noticeable.

Were the smaller transformers in a certain generation or board set of game vs the larger?

Man, it is so interesting to me learning all of this stuff so thank you everyone for posting information!

Thanks for the info. I don't know the full history of my Quicksilver, other than it was owned privately for the last 20-25 years. Maybe the export models were specced differently?, I'm not sure.

What would I notice with the larger power supply? Stronger pops, slings and flippers? My lights do lightly flicker when the flippers are in use, so being under powered does make sense.

https://sites.google.com/site/allentownpinball/galaxy-asm/cheetah-rev-b16-tournament.zip?attredirects=0&d=1

it's a good thing gmail archives everything so I don't have to

Yes.

On the left is a Stars MPU-100 transformer. On the right is a Big Game MPU-200 transformer. The voltages are all the same. But Fuse F4 on the MPU-100 (16B-3 transformer ) shows a 5 amp fuse being used. On the MPU-200 (16B-6 transformer) shows a 7.5 amp slo-blo fuse bing used.

The F4 circuit is for all of your solenoids which include pops, slings, and flippers. You can see this information on the paper glued on the rectifier board that tells you what fuse to use.

Other than this F4 circuit, I do not know what else is different with these two transformers other than the physical size and that the larger size has more wire in the windings.

Stars is considered a great pin to play but it has the small transformer. Some people like Dracula but it also has the smaller transformer. I have never played those 2 pins and cannot make a comparison. But I have played Nine Ball, Dragonfist, and Catacomb with the smaller transformer. Dragonfist played OK. Nine Ball played OK. Catacomb played like trash. But with the larger 16B-6 transformer, what played OK turned into some hot playing pins.

Some say they can tell no difference in play action. I can.

Screen Shot 2020-08-16 at 7.48.01 AM (resized).png

Here you go. You can print this out for ready reference; The black goes away.

http://members.iinet.net.au/~lantra9jp1_nbn/gurudumps/Pinball_Manuals/stern.html

(thank the guy in Australia for putting this info. up)

The turning point is at Magic/Meteor. Everything up to and including Magic are MPU-100 Sterns.

Everything from Meteor on are the MPU-200 pins. I cannot speak to Cue or Orbitor 1. The MPU-200s are the ones being talked about when classic Sterns are the subject of conversation.

The changeover was made when they went to -200 games starting with Meteor. I seem to remember someone posting on RGP years ago that the -6 transformer was created, so Stern could use 4 flippers with their games, and not have any current lag on the solenoid bus. Some of the -100 games have 3 flippers, but none have 4 flippers.

I'm pretty certain that I have a -3 in my current Flight 2000, and I do not notice any difference from my last F2K, which had the correct -6 in it.

Also in that vain, Stern playfields shifted to long-shots and wider playfields.
Then add the double playfields on top, plus flipper redesign and new flipper winding's.

I know these can be hard to come by

ebay.com link: Stern Electronics standard body pinball lockdown bar 1979 1982

The link above works but the download links all seem to be dead,it comes up with below.

This... is kind of awkward.
We can't find the page you requested. (Error 404)
This page might have been removed, had its name changed, or be temporarily unavailable. Please check that the Web site address is spelled correctly.

This may have been answered previously but my search attempts havent found anything yet. So figured i’d just ask the crew here:

What is the optimal playfield pitch for a classic Stern. Say a Seawitch. 6 degrees? 6.5 seems difficult to get to with no support nut under the front legs and the back are jacked up (3” long levelers). I’m measuring in the open area in the middle of the playfield. Up top in the pops is a wee bit steeper than down by the flippers.

Get yourself a pair of 31” legs for the back. Those will put you up in the air. Then make your slope adjustments from the front legs.

I think I have my Big Game set at 7%. The others are around 6%.

Can someone check their mpu100 “button” lockdown bar and see if there’s a part number stamped on the backside of the lockdown bar? There’s a part number stamped on both of the mpu200 versions. I’ve listed them below for reference. I found a guy with several lockdown bars for sale, so I’m trying to identify if any of his are classic Sterns.

Mpu200 - with slots for the latches:
Standard - Stamped “Stern 1C-707”
Wide Body - Stamped “Stern 10-707.” Also can be identified because it’s two smaller lockdown bars welded together with an obvious seam.

Mpu100 - with “buttons” for latches:

Not sure if this helps - from the Stern parts catalog. The MPU200 part number doesn't match what you've listed.

Stern_LockdownBar_79.jpg

Here are pictures of my mpu200 lockdown bars.

625C19D8-A34E-44B6-91D5-6342AEAA7767 (resized).jpeg9989DCB4-F6F0-47D9-BB93-3816C5B5E196 (resized).jpeg

Anyone have a Stern Electronics coin door flap and coin reject rod laying around that they would be willing to part with? In the alternative, can someone point me to the appropriate replacement parts at Marco or PBL? I see some options there but don’t know for sure if they would work or not. Thanks in advance.

The “IC-707“ is the part number for the copper latch bar only.

I’ve been on the hunt for a coin flap for a while. Not easy to find it seems. There is an aftermarket option with Cliffy if you get stuck.

http://www.passionforpinball.com/blycoin.htm

Very helpful. Thanks for the information!

They may have also made the 16B-6 larger transform so that it would run cooler than the smaller one. All the other non-flipper solenoids are behind the 1A - 1.25A S.B playfield fuse so they weren't really gaining much for the other game features by adding the larger transformer. Maybe they changed it to handle more flippers and/or increase the flipper strength. It does seems like the change to the larger transformer was related to the flippers.

I'm interested in the tests you did with Dragonfist, Nine Ball, and Catacomb. Did you use the same games but swap the whole board with the mounted transform/rectifier board? A friend of mine has a Stars and the flippers are very strong. I'd say they were on par with my Nine Ball and Seawitch. I have a Pinball and the flippers always seem weak. Stars and Pinball should have the same coils but since it's not an apples to apples there could be some other differences.

Quite a handicap you’ve got on that Big Game.

The catalog pictures are for narrow lockdown bars and Stern's Big Game has a wide body
lockdown bar.

I bought that project plus a really nice playfield for $550. I wasn't going to complain as I already have two parts playfields with flipper mechs.

Thanks for the replies. He can identify the mpu200s by the copper latch bar assembly. I still need someone with a mpu100 pin to see if there are any easily identifiable parts on the back like the copper tabs on the mpu200 pins.

There isn't.

Any reason the seller can't just send you pictures to see if they have the MPU100 stud pins?

Cheetah players. Please give a quick rating. This one deserves to be in the top 100 list. We need about 5 or so rating to get it there.

Thank you!

I offered the link as a ready reference for all of the Stern pins in order of their production, with a small pic to help you ID which Stern it is.

I couldn't care less about the rest of the links.

You would have to contact the guy in Australia who put this link up.

Here are some pics of my button style lockdown bar. There are no part numbers. AFAIK, Stern is the only company to use this type of lock bar. So, if you see the telltale nut plates that are spot welded on they will probably be the bar that you want.

This bar came from a roached Dracula I bought.

Caution: Those screws (buttons ) are not standard off the shelf screws. If they are missing then you will need to visit a machine shop to get them made.

IMG_4260 (resized).JPGIMG_4259 (resized).JPGIMG_4258 (resized).JPGIMG_4257 (resized).JPG

Thanks, that’s what I needed.

The only mpu100 pin that I own for reference is a Nugent and it’s missing the lockdown bar.

Nine Ball came with the smaller -3 transformer. There is a burn mark in the cab suggesting the original transformer had been fried. Sure, I noticed the smaller size transformer but did not know enough to put 2 + 2 together. NB played OK. I was none the wiser.

Dragonfist was shipped to me with the smaller transformer. I bought it from a respected pin retailer with lots of pinball experience; Am am certain he knew what he was shipping. For a couple of years I played Dragonfist. It played OK but I cannot say I was thrilled with this pin.

So, once I figured out the lay of the land with this transformer business I started playing around. All I did was swap in a complete assembly from one of my other Sterns. The difference in play action was quite noticeable on NB and Fist. I don't know how to explain it but the -6 transformer offers just a little extra pizazz. Once you taste it you don't want anything else.

Catacomb was worse. I lot of people do not like Catacomb. I do. It is smoking fast. I placed one of my -3 transformer assemblies in Catacomb. It was not playable. Slow as an old dog.

This is my experience in using the two types of transformers. I offer it for what it is worth.

That is what needs to be found out re: the transformers... what's actually the difference. I wouldn't put any stock at all in the differing fuse sizes since there were labels or notes in the manuals that say 5 amp for 2 flipper games, 6 for 3, and 7.5 for 4. Same -6 transformer on the back end there. Last time this was touched upon the question becomes, how do you actually wind a transformer for extra current etc. and how can we measure what's different.

None of my mpu100 games (stars, hot hand, previously dracula, wild fyre, trident) had 'weak' flippers, and I've had 3 different Stars, all of which had strong flippers. Of course, they were rebuilt, which certainly does make a difference. Even something as simple as the wrong EOS gap is going to make the flipper seem weaker. (I use this to my advantage on meteor and seawitch to eliminate the dropping resistor in those 2 games to weaken the upper left/upper flipper).

Also, the coils changed at some point as well, for a while in the mid 2000's people were going crazy getting the -450 and -475 coils into their classic sterns - which of course are going to have a stronger stroke vs. the 500, 550, and 600 coils. It depends on how hot-roddy you want to make your game.

The Dracula I bought had the button style. The Hot Hand I bought had the later slotted style. I think Trident has the earlier button style. So HH must be where the switch was made.

Personally, I like the button style because the buttons/screws can be adjusted to make the lock bar fit better. With the later slotted style with no adjustments, is is important that the lockdown receiver is placed correctly on the cab.

IMO, it is a another case of Stern looking for a cheaper way of building a lockdown bar. It had nothing to do with the slotted style being better but being cheaper to build ( I'm not knocking Stern for looking for a cheaper way to build something).

I agree. I wish I knew more about this stuff. The only two items I can see that are different is that F4 fuse callout and the difference in size.

Actually, my Nine Ball had a Bally 122-125 transformer as replacement for the NB transformer. It took awhile to figure that one out. I study the Stern blueprints and the Bally blueprints and 16B-3 and the 122-125 look the same. I know that Stern had its transformers built by a company called Ravenswood on Chicago' north side. I'm guessing that Ravenswood probably did work for Bally, as well. It would take someone a lot more knowledgable than my to figure out the engineering between the -3 and -6 Stern's.

All I know is there is a difference in play action. At least, I can feel it.

Now I am wondering what a Stars would play like if it had the larger -6 installed.