Submarine (Midway EM Game from 1979)

[speleo_de]

Helping friends to get a non-working Midway Submarine back to life - we are not finished yet

We had two repair sessions, one in December last year and one more in April 2013. I want to share some interim results and pictures.

December 2012
John from flippers.com was so kind sending me the ROM dumps, so I burned two EPROMS in preparation. Our repair session was not too effective, I think I have to get used working together with another person.
Boards are in an L-shape like many of the early Midway boards. We were able to get the CPU board tested with my Fluke 9010A and working. The original EPROMS were dead, so luckily we had the new ones . Strapping on the board needed to be changed as the original EPROMS were the TMS2716 kind with three voltages and the new ones good plain 2716 with just 5V. Interesting that the four 6810 RAMs were still ok.
With the I/O board we failed miserably. Someone had worked on the board before, that was clear. So we replaced the missing components and did quick check on the rest. That was the problem: we should have checked more intensively !! When switching the machine on, 3 transistors got extremely hot and we were not able to fix that during the remaining time.

Finally I took the boardset home and worked on my own place, did a minimum power harnes and simulated motors by some power resistors, required inputs simulated by switches etc ... I found out that several mistakes were made by the guy who had tried to repair the I/O board before. I fixed that plus two of our own introduced mistakes and now CPU and I/O are at least working on my bench. The CPU board had an additional issue with the 'noise' generator and need a new CMOS 4006 - 18 bit shift register.

To be continued to test the I/O and sound with the Fluke on my desk...

[speleo_de]

April 2013

We've got some signs of life here.

OK, understating :-) The game is basically working now with the exception of registering the torpedo hits.

I had some repair & test sessions on my workbench for the PCB set. Finally I fixed some further issues that were introduced by a person before trying to repair. Then I tested inputs and outputs with the help of my Fluke 9010A: lights, motors, sounds - a lot of I/Os. Pretty confident that the boardset was ok, we arranged a 2nd repair weekend at the machine's site in Coburg ~250 km away.

After installing the PCB and powering on the machine, the initial view was good. Sonar sound came up and displays looked fine, but then we realized that the target moving motor still was stuck in one direction and didn't react to the limit switches, the switching transistors became hot again. Soon thereafter the +5V dropped to +1.1V and finally the fuse blew for +5V.

An investigation showed that the power regulating transistor for +5V was blown as well. Replacing that and the fuse we powered up again with little hope for positive news - and indeed, the target motor had the same problem. Checking power we didn't found a real issue, although the unregulated +/- 14V were a little on the high side (17's). We powered off for that day and put the boardset onto the workbench again to validate it was still working there... yes it did. We then put some thinking effort into the issues for the next day.

The next day we looked into the basics - and we found the issue that probably was present fom the first day the machine was here in Europe: The power transformer was wired for an input voltage of 200V and this in a region on earth that, since ages, has a minimum of 220V. Today we're more at 240V... Luckily the transformer has also a lug for 240V, which we resoldered the mains to.

The change from 200 to 240 VAC input voltage was a full success. All motors working, sounds working, coins and start recognized, torpedo launch ok.

We then adjusted the torpedo mechanism cleaned/lubricated the machine and took some pictures and a video.

Only issue left is to replace the torpedo lamp and check/verify the target hit lamp & sound circuits. The original torpedo lamp is kind of rare here (BA15s, 6V, 3A and FC6 filament), so we need to use a 'cross' version.

Todo:
- Replace Torpedo Lamp
- Add Key lock
- Replace feet
- Final cleaning of periscope

Now enjoy pics and video - to be continued... :

VIDEO - http://www.youtube.com/watch?v=8s-ZMKHGg3o

[speleo_de]

Some more pictures ...

[Laszo]

I love these repair stories, thanks for sharing! You mention that you found several other issues while repairing, would you be willing to share them with us? Imho 99% of the isues in certain boardsets and even board architectures come down to the same 5 failures or design flaws. 

I still got a logi tec space invaders with a 8080 architecture I need to repair, so really interested in any faulty components found. 

[Belike]

The more EM games I see, the more I fall into love with them.
Beautiful one, thanks for sharing.

[level42]

Great cab, great story Andreas Very rare to read a report like that from you and most welcome IMHO   , I love reading this stuff

[ckong]

Very nice, I love the ´ping´ sound, gives it a really atmospheric ´das Boot´ touch.  

thanks for sharing.

[speleo_de]

I love these repair stories, thanks for sharing! You mention that you found several other issues while repairing, would you be willing to share them with us?

The other issues were mostly "issues that were introduced by a person before".
Specifically I found in the analog section of the I/O PCB:
- quite some resistors changed to different values
- diodes replaced by resistors (circuits changed)
- one factory installed jumper removed
- many traces and through holes damaged
- one 5Watt resistor fried
- TIP31 and TIP32 transistors bad
- one LM3900 in the sound section
I think someone tried to get it working with the higher supply voltages... and used improper tools for removing/desoldering parts, making things even worse.

In the CPU Section I found:
- bad EPROMs with a bad jumpering in addition
- bad 4006 shift register
- bad 74LS138 3 to 8 decoder

--------------------------

[DarthNuno]

I'm totally in love with that Submarine! I had great memories on that one!
I played it during several years (still in the same Luna Park). I've never seen/played one for real since!  This is what I name a rare cabinet!
Wanna trade it? 

[speleo_de]

I played it during several years (still in the same Luna Park). I've never seen/played one for real since! 
Wanna trade it? 

Hmmh, maybe its the same one that you played on.
Where was/is that Luna Park?
IIRC it is set up for Francs...

And no trade/selling for sure.

[Laszo]

You guys did not mention how big and heavy these submarines are 

[Laszo]

...

[level42]

What, you got it ?!?!?


 

[ataritoobin]

Namco version?  Hawt 

[Laszo]

What, you got it ?!?!?


 

Yep, I got it  the owner called me, he needed to clear his storage space and this sub was there allready for many years. He was reluctant to let it go out of site, so he called me to please pic it up  He wanted to make sure it would get a good new home. So I picked up the beast...... We tested it and it started..... But still a huge project to restore it in full working condition. For one the plastic cilinder with the clouds is missing...... Anyone have one available? Opto's and sound are also not fully working.