1981 Gottlieb Black Hole Pinball Restoration

[wonder]

Very Nice Indeed.

[4_amusement_only]

Great work, looking forward to further progress of this thread.

[zitt]

Darn, I got side tracked on a new project and forgot to post several updates. 

- Sat Oct 30, 2010 9:50 pm -

For the past several weeks; I'be been working on the electronics on the machine. Designing new PBDBs, debugging bad connections, installing new coils, etc. One of the problem boards is the System 80 Sound/Speech board. This board was a pull from a Haunted house which did not have the SC-01-A speech chip installed at U14. The game features a robotic voice courtesy of this chip; so I had to have it.

For the last two weeks I've been debugging the board after ordering the rare $40 chip from Kevin @ GameRoomRepair.com. The sound effects were fine; but the speech was causing a horrible wabble effect on the audio output.

Since I had no working board to base functionality check - I had to brute force the debug.
After replacing nearly 100% of the Speech logic - I found out that the R6 pot was turned all the way down which prevented the multivibrator of Q1 & Q2 from oscillating.

I determined this by looking at the SC-01-A datasheet where they had RC set to 6.5k * 300pf in their reference circuits. After some experimentation; I determined that a 11kohm [Brown, Brown, Orange] (from 12V to the C22 cap) and the original C22 300pf cap would "clock" the speech chip and allow it to speak in test mode. Measuring the top of C22 in this config seemed to give me ~5V sawtooth waveform at ~530kHz.

I then removed the 11k resistor and adjusted R6 to ~530kHz. Why not 720kHz as described in the datasheet? Well; it appears my 20pf scope probes load the multivibrator enough to decrease timing by a significant margin. By adjusting to ~530kHz, the robotic voice sounded about right without the scope probe. Keep in mind that if you test with the scope probe attached; the voice will be slower than normal so do not adjust the R6 pot to proper speed with the probe attached.

I've documented this here so others can have a means to verify the clock circuit without replacing the entire section like I did.

Click Me to Enlarge

Hope this helps someone in the future.

[zitt]

- Sun Jan 23, 2011 11:32 pm   -

The machine I purchased had a broken black box door where someone broke the wood to gain access via a lost key. I picked up a replacement from a fellow RGPer who was parting out a black hole. I started by removing the hardware, filling the holes with bondo, and putting a coat of sandable primer


Then followed up with another round of bondo:


Once the door was sanded to 220grit; several coats of auto black  were sprayed on the door:




Hardware Before:




After Polish:






Wood Epoxy + Bondo:






The top need some TLC:


some 220grit on the orbital sander:


Wood glue + bondo:


And some blue paint to polish it off:

[zitt]

And to finish off the cabinet work:


More wood epoxy; bondo; sandpaper; and paint:

[zitt]

The flipper bats had yellowed with age; so I used a solution of Lorne's Retr0Bright to return the flipper bat to a bright white:

No... really that is an original flipper bat; looks brand new, huh? I was honestly shocked by the ability of the retrobright to work on the bat.

Then I needed to embilesh the flipper bat a little - so I created a couple of designs in coreldraw:


And decided the simpler one would look better; so I printed the design on clear water slide decal paper:


Here's a comparison of the newly modded flipper bats:


I actually printed two sets of water slide decals and layered them over each other to give a more solid black:

Bottom has two layers. Top is a single layer.

Not pictured - I put three coats of clear laquer over the flipper bats to protect the decals.

While I had the Retr0Brite out; I put them to work on the other white parts:


Here they are getting some Rays (UV/Sun):


They proably could have used another day in the sun; but I had a Xmas Deadline quickly approaching:


After reassembly and some final adjustments - the machine was ready for Santa. Stay Tuned.

[ktm450]

That looks great so you use a proxide mix to 'blonde' up the bats, does it slow them down? 
Looks great and works a treat, love the decals too, great work 

[zitt]

That looks great so you use a proxide mix to 'blonde' up the bats, does it slow them down? 
Looks great and works a treat, love the decals too, great work 

lol - no; New rubber + clear coated PF = anything but "slow". :>
Here's the final pics I just uploaded to flickr. I'm going to try and work on the video I captured in the near future.‎'twas two days before Christmas and all thru Steve's house ... Not a creature was stirring except maybe a jolly old fat man ( aka Zitt ) installing his brothers' new pinball while visions of sugar plums failed to dance in his head. ( brother was asleep )

SURPRISE!
:)

Click Z pictures for high rez shots.




Even Grandma had to check it out!

LED inserts were used to lower power consumption, brighten the playfield, reduce insert damage caused by the original bulbs. GI circuits and black box remain standard bulbs.




Lower Playfield also received LED inserts.








And last but not least; the flipper buttons received a set of the Star Trek Flipper mod circuit boards; except all the LEDs were red this time.

[pinnies4me]

Inspiration work there, makes me want to tear my BH down and purdie it up too, but I can't stand the idea of it not being playable, such a great game!

[zitt]

Machine in Gameplay:

[ Invalid YouTube link ]

&hd=1

[goodolddays]

Great job  Sure wish my brother would surprise me with one of these restored to your standards 

[Strangeways]

Very, very nice !

Any other projects in the pipeline ?

[ktm450]

Great job, love the shot of grandma playing 

[zitt]

Very, very nice !

Any other projects in the pipeline ?

Projects are not a problem.

ATM; I'm working on a Sega Star Trek Captain's Chair...

Still need to restore my Data East Star Trek and my Williams STNG. However, both of those are players condition - so won't need the level of restore the Bally ST or the Black hole needed.

Thanks to everyone for the kind comments. Sadily; I really enjoy these big restorations.The problem is I always seem to spend more money on them they they are worth. 

[solar value]

This looks fantastic, amazing attention to detail.  I remember playing this game in Las Vegas as a kid when my parents took us on a holiday across the US.  Totally forgot about it until I got back into pinball a couple of months ago.