Central Park: Done and gone!

What a great little game Central Park is.  6 freaking ways to drain, 6 freaking opportunities to fine tune your nudging.

This game had an intermittent tilt mech, so I took it out, cleaned it up, and now this machine is BRUTAL. 

Like if you were going to play it in a tournament, you'd optimally want to wait 5 minutes between balls to let that bob settle.  If it was my game, I'd probably remove the bob and just have the wire dangle.  But it's not mine, and the home it is going back to is of a competitive player, and this will test his mettle.

There were a few annoyingly intermittent lights sockets, but those got cleaned up and taken care of. 

The final big thing was the 1000s relay (HB) which wasn't pulling as we rolled over the 9 hundreds reel.  Bulb was loose, carry bit on the hundreds needed cleaning, and the normally closed contact on the HB relay itself all needed some attention.  But now it pulls and performs it's singular function:  lighting up the 1k light! 
It is also used in the replay scores, but since I have the credits unit disabled on this machine, it's effectively a bulb control.

this is the control bank relay bank, which gets a hard reset when a new game is started.  HB is the rightmost one.

So long sweet Central Park! 

You came here non-working and a bit dirty, and are leaving well loved and working and clean.

Central Park: mostly working!

With a local women's event coming up, I really wanted to get Central Park playing adequately, and there were a few problems to address.
The Yellow (1-5) and green (6-10) are their own separate banks.  Sometimes it seemed like not all of the numbers would properly reset (light) on each bank.

One big issue was that the 1-3-5 rollover was reseting the bank entirely!
I did some testing and realized it was any of the 1-3-5 or 6-8-10 rollovers that would do this.  When those are hit they lunch a relay that pulls down those individual relay banks.
The 2-4 and 7-9 rollover switches just try and pull both of their numbers down at the same time.  Some time this fails, meaning I probably need to clean those.

But on to the other relays, causing the resetes!

click to embiggen!

I started my search at this point in the schematics, thinking a short along the B and X switches allowing the 1-3-5 rollover to trigger a reset.
But that was before I realized the 6-8-10 was doing the same thing.  After spinning my wheels on the above stuff, the X and Y relays especially, I checked specifically the reset logic:

click to embiggen!

So while the X and Y relays are used to reset, so is the SB relay, so I inspected the Brown wire there, and that was the issue:

Not on, the switch is closed, and it shouldn't be.

and when closed, it is closed.  As it should be.

These switch banks handily pivot out for working on them.

After regapping that switch, those rollovers no longer caused the resets!

I tested the 5 targets, but then noticed a new issue:  The X relay was coming on, but then locking on!  Uh oh.
Why was it not locking on?  Check the top schematic, it is supposed to release on a motor position.  But, the motor wasn't running.

Why wasn't it running?

Yeah that wire probably goes to that empty lug.

With that reconnected on the X relay, the Y releay also required cleaning and adjusting.
With that taken care of, both banks were scoring properly and reseting when they should!

One downside of this game, if and when you get the middle targets past the 50 point mark to Special, they stop scoring.  For an EM game, specials are worthless.  I might consider modifying the game so it tops out at the 50 points mark.... hmmm

Oh and this was also in the 6-10 (+SB) bank.  The reset solenoid sleeve:

Yes, that is a crack that, like lightning, comes down, then does a 400+ degree rotation through the sleeve.

Still a few things that need to be made more reliable.
Locks need to be added to the back box and coin door...
LEDs need to be added to replace burnt bulbs...
But, mostly working!

Central Park: getting it running!

Like a rat in a cage desperate for a food pellet but wary of the button that last shocked her, I stood pensively by Central Park.
I needed to play!!!!!!!!!!!

As oft with line voltage issues, I bring in external help to assist and verify.  I've been zapped a few times, and I want to limit it as much as possible.  We don't need any after school specials about how kids should avoid getting involved in pinball for fear of death by electrocution.

We put a lede on the door frame and started testing to find the short.  At first I thought the short was before the door connector, but it turns out it was the coin chute shorting to the metal frame.
Let that sink in:  metal coin chute, metal switches, metal door, and LINE VOLTAGE RUNNING THROUGH IT ALL.
I am going to be disconnecting the coin door wires altogether.  No point having extra line voltage running to the front.
As well, removing the slam tilt connection from the coin door.  Also line voltage.
I will just leave it at the start button.
This is a 1966 game.  No one cares for classic coin action startup behaviour and such, let's just get playing!

the jammed coin switch

In addition I took out the single piece of dried electrical tape buffering the metal button to the line voltage switch stack.  Replaced it with 5 layers of thick fresh electrical tape, and realigned the fish paper.
Once the jam was cleared the front was no longer electrifying!
I still want to do those mods to reduce the chance of future issues.  As it sits, it is one kid with a quarter away from fudging their way to an electric shock.


Oh hey, did I mention we got the game working?

WOOOO

The last barrier to getting the startup going was the "ball on" stack. 
A solenoid pulls down a lever that lets all of the balls queue up to the shooter lane.

here is how it was when I started:

how we found it, resting position

bent in to shape

At the bottom of the photos you can see the metal bit that pushes the stack outward.  That pulls out and closes the stack, and lets the balls in to play.
That solenoid is buzzy and stays active until any points are scored. (It's locked until the 10 or 1 point relays fire)

oh right the credit unit

One other thing required to get it running properly:  this buggy little credit unit.
Not only is the clock spring wound around the post on the cog, but there is a DELIBERATE short such that it will continually decriment the stepper past the zero position.
Let's look at one special detail in that photo:

well hello dancing wires

You can see the two wires at the front/top are BRAIDED TOGETHER.  When the switch hits zero position, the gap opens and thus the solenoid is not allowed to lower it any further.  Braiding the two wires together means it will ALWAYS be able to move past zero position, which is why we ended up with the overextension of the stepper, and a short amongst the switch plates.

Someone did this on purpose.  They are my nemesis.


With that all taken care of, the game played!

Some problems:
On the left (yellow) bank, numbers 1 and 2 were not going out when hit.  Under the playfield I closed those relays manually and they locked on.  (each number, 1-10, has their own relay.)
After that, those numbers work A-Ok.  They always say that the best maintenance for an EM is to play it regularly, and I think this is one of those situations.

After that, one big thing that immediately stood out was that when the green (right) number bank was completed, everything reset.  The left, when completed, would not reset.
I took a look at the bank of 1-5 relays and thought there might be a switch, like Surf Champ, where if all are on, it indicates that the bank is complete, triggering something else.

Here is the bank of 1-5, under the playfield.

these Gottlieb banks have these handy screws that allow you to readily rotate them to a more serviceable position.

I saw this odd switch poking at relay #2.  I had a very hard time seeing what it was up to though, even with the grace of pulling the relay bank outward.

well hello switch, you look like you do something!

from the other side, I added probes to make sure I could test the switch connection

So this switch had issues.  It was not closing when the #2 relay dropped, so with a bit of cleaning and bending I got it working.
Closed the machine, pressed start and...  BUZZZZZ the coil was locking on!  Easy fix though:  I had forgot to resecure the screws for that relay bank.  duhhh
That taken care of, game started properly.
And while this wasn't the fix I needed, it did help.

That odd switch I found was just used by the X relay reset sequence, so that game was no reseting certain cases a little bit better.


So there are still a few big issues:
The 1-3-5 rollovers just resets the yellow./left bank outright.
some of the rollovers lights all available, instead of just a single.
The left/yellow bank doesn't reset on completion, ubt the right/green resets all on completion.
the #7 light socket has issues, probably needs to be replaced



 so, plenty to look in to!

Central Park dabbling

I'll get this out of the way:  I am still scared of Central Park.  I can't bring myself to touch the front panel with it plugged in.

Check this start /"Replay" switch at the front of the machine.

ummmmmmm

Let's review:
The front plate?  metal.
Start button?  metal.
Switch stack?  metal plates.
Activated by?  Metal button pressing switches.
Switch voltage?  120V line voltage.
WHAT THE HELL COULD GO WRONG???

There was some worn fish paper and a piece of dried electrical tape.   What the hell kind of design was this?  Next time you complain about your electrician bill, please remember that safety codes are updated for very good reasons.

I wanted to play around with it a bit so I went out and asked the pinball community for an isolation transformer.
These are common in Ontario as, probably due to machines like we have here, were mandated by Ontario Hydro.  In a home environ with everything gone over, not really needed, but for the older games they were a great idea.
I even pulled one of these out of a Baywatch way back when.  For newer machines, they are still somewhat useful if one machine has a ground issues and someone touches lockdown bars on two machines in a row.
But everyone pulls them out because even if the game is off, they still draw a bit.

A quick aside, that thread I linked above had lots of gem information, including details about the bounce switch we had pondered in this machine.  A message I sent a friend:

Yeah, so that's a thing.
I so want a 1960s video of an operator going down the rows KICKING each of his machines to "turn it off".
WHY THE HELL WERE ON/OFF SWITCHES AN OBSCURE CONCEPT?

But here it is, in all of it's glory.  The circular metal bar in the center of that round plastic goes all the way down to the bottom of the cabinet so that yes, it can bounce if kicked.  If that circuit is opened, the voltage to the transformer temporarily disappears, the hold relay has lost power and disengages, turning off the GI and all power on the other wise of the transformer.

I got an isolation transformer from another collector in under 24 hours. rescuing it from the recycler:

this thing is over 10 pounds.  You could develop a workout regime around it.

One thing to note:  apparently if these things get hot, they are bad.  In the thread I linked, an operator relates the story of one catching fire in his workshop, and luckily being noticed immediately.


I put 5 layers of electrical tape in a stack and used that to buffer the start button.  Even with the isolation transformer and fresh tape barrier, I still pressed that start button with a plastic funnel.
I couldn't do it otherwise.
The game started chunking forward, but I went around back and noticed a whiff of smoke.  OMG NO!
Unplugged it right away.

I took a look at the rear stepper unit and behind it was this badass oldschool resistor.  But neither it nor the stepper solenoid were warm.

this might as well be a prop on The Flintstones

Next day:
Upon getting the machine, I had previously swapped out 2 x 20A fuses with 2 10A ones.  the main line fuse was 15A, but should have been 5A, so put that one in.
I raised the playfield and turned it on so I could better identify where the issue was, but aside from buzzing on the continuous solenoid relays, I couldn't find anything noticeable.  No smoke. 
I remain paranoid.


So instead of going further, I wanted to at least do something productive and clean the player stepper unit.

You can see the grime on all of the rivets and their paths

first look with the outer plate removed, only a bit of sanding done in the upper left.  Note how dirty the points are.

cleaned and reassembled.

Next week I'll see if I can start muster the courage to "solve" the start button issue, and hopefully find what was smoking.
I just want my game to look like something other than this:

Introducing... Central Park!

Helllllllllllloooooooooooooo beautiful Central Park!!!

Sinbad left the basement to be shared at the 5th annual Ottawa Pinball & Gameroom show.  After that it went to a friend's house for a while, freeing up space for an extra project!

oh wait, something's not right here.

 So this machine was delivered as NOT WORKING, a challenge I readily accepted.

I left the playfield out so I could take a look at the transformer and all of them guts.
First thing though:  checking all of the fuses,  IT'S JUST A FUSE might some day be true.  Not the case here, all fuses worked, thought 2 slots had 20s instead of 10s, so fixed that.  All others, fine for continuity.

Just for a lark, I plug the machine in.   I go to hit the on button to test, and.... there's no ON switch.  Nothing.  Not sure what year they started using ON SWITCHES, but 1966 wasn't that year, let me tell you.
The game is supposed to be on just when plugged in.  OK, that seems perilous.

Next up was tracing the line voltage from the cord through the machine.  We start at the live line and attach a DMM node there.

we start at the beginning, Sherlock!

these 2 switches provided continuity.  The one on the right is extra odd, and would only seem to break if the machine was basically upside down, but I'm guessing people were rowdier in those days.

After the security switches, the line voltage comes to... this panel at the front.  Then connects via plug to THE COIN DOOR.  OH GOD DON'T CONNECT LINE VOLTAGE TO THE COIN DOOR.

Let's say that again:  OH GOD DON'T CONNECT LINE VOLTAGE TO THE COIN DOOR.
Stupid security switch there...

I then traced the return wires over to here, and you can see the black wires runs parallel and continues on...

And here is where the black wire runs to!  This is the hold (R) relay.

 At this point I dug out all of the long-detached labels and noticed the title...

ONE HUNDRED AND FIFTEEN VOLTS, ARE YOU KIDDING ME?

Yes, this is a stupid relay that allows the 115 volts to continue.  that's a lot of voltage to pump through a relay.

Using a wooden chopstick, I closed that relay and it LOCKED ON immediately.  The game motor ran, the lights were on, and the score reels reset to zero.  PROGRESS!

But now, why wasn't the hold relay coming on normally?
To the schematic!

Ok OK, I don't have a Central Park schematic, but I do have one for a 1963 Slick Chick, and while not 100%, will basically do the job.

CLICK TO EMBIGGEN!

Take note of that circuit.  one key thing is the 6 volts on the top side of the transformer.  That powers the lights.  If you don't have GI lights on, you're either getting nothing on that side of the transformer, or every single light is out.  A quick test with the DMM confirm that the transformer isn't powered.
So how does the power make a circuit?  The bottom line of the schematic is the line of switches we tested, but the SB relay needs to be activated to complete the circuit.  SB is activated by the coin chute or by pressing the replay button on the front with credits in the unit.

At this point I took a look at the credits unit up in the head:

No, I don't think that coiled wire is stock...

So there were 2 things odd with the credits unit:  This wire was wrapped around one of the poles that moved with the cogged disc, preventing it from advancing.
Also, when it went clockwise all of the way it went too far and would short the two switch banks.
I took the wire off from around that pole, and added some credits.  One other odd note:  The wheel that displays the credits is entirely misaligned by 180 degrees, so whether at zero or 15 credits, nothing will be displayed on the front.
I think my end strategy for this will be to jumper the switches and not have the credit wheel move, and always have the game on free play.  I don't need this mess.
But I also think it was mucking up the game.

So I've traced the SB (start) relay, it is on the backside of the playfield.  I think I've solved the main issue, a funky credit unit needing lots of love.
With everything connected, I plug the game in again and boom, all of the lights are on immediately.

I go to press the start button, aka the "Replay Button" and BUZZZZZZZZZZZZZZZZZZ
I depress the button, but am rewarded with a big electric ZAP.
the game starts, the balls are released, but I don't mess around with line voltage.

There is still a short somewhere.
Time to bring in some assistance and hunt down the short.

In the meantime, I get to start cleaning this beautiful dirty game up.