Help to identify chip

speleo_de

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"SLAM" from Mirco Games (1975)

Hi,

just working on repairing the PCB Set for this table "SLAM II" from Mirco Games in 1975 :
http://flyers.arcade-museum.com/?page=flyer&db=videodb&id=2535&image=1

BTW I seem to have verion SLAM II (not just SLAM) with the MODE Select Switch and Start Pushbutton on top of the table.

Its a 'PONG' extension for four players and Paddles can be moved across the playfield vertically and horizontally. Repair is a challenge with >100TTL Chips and no schematics. Have worked my way with the help of an HP logic comparator HP10529A and replaced some faulty chips, still not there, as collision detection with the paddles isn't working.

Have also identified all chips but one....

Is anyone recognizing the Chip in the middle of the small picture " 542 7529" ?

It may be a sort of monostable multivibrator, as the outputs are changing their duty cycle with paddle movements and caps/resistors are connected to it.

Thanks
 

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Hi,

just working on repairing the PCB Set for this table "SLAM" from Mirco Games in 1975 :
http://flyers.arcade-museum.com/?page=flyer&db=videodb&id=2535&image=1

Its a 'PONG' extension for four players and Paddles can be moved across the playfield vertically and horizontally. Repair is a challenge with >100TTL Chips and no schematics. Have worked my way with the help of an HP logic comparator HP10529A and replaced some faulty chips, still not there, as collision detection with the paddles isn't working.

Have also identified all chips but one....

Is anyone recognizing the Chip in the middle of the small picture " 542 7529" ?

It may be a sort of monostable multivibrator, as the outputs are changing their duty cycle with paddle movements and caps/resistors are connected to it.

Thanks

Good guess - you can also build multivibrators from nand gates. Sometimes the chips were house numbered due to variations in spec. You do have a mystery on your hands.

Bill
 
Thanks so far. At one time I may put the circuit around this chip onto a piece of paper, if no one is recognizing this IC. FWIW, the surrounding is all TTL plus two 555 timer circuits, nothing else.

Also for reference I have put up a small webpage for this machine:

SLAM or SLAM II
MIRCO GAMES
Division of Mirco, Inc.
Phoenix, Arizona

http://www.andysarcade.de/projects_slam.html
 
check out Paddle Battle.
I bet they are real close. If not a clone of each other.
 
andykmv said:
this one is from fairchilds 1977 databook: http://www.datasheetarchive.com/7529-datasheet.html...

Unfortunately as arcadenut was stating, this is a DIP16, and mine is a DIP14.

check out Paddle Battle. I bet they are real close. If not a clone of each other.

Good hint, I looked it up -- Paddle Battle is using standard NE555 Timer circuits with DIP8. This made me check if there is a QUAD timer version of NE555 and indeed there is : NE558 -- but also DIP16 Package :(

Now did some reverse engineering and started a schematics, maybe this helps. It seems for me, we have a Quad Timer circuit with all 4 timers running the same base frequency, determined by an RC combination and the duty cycle determined by another RC per each of the 4 inputs. Link to partial schematic: http://www.andysarcade.de/projects_files/slam_1011_3701_schematic.pdf

Thank you for all of your your help and ideas.
 
Very interesting, another Mirco Games! But seems a to be a different game:
It has turn-knob rather than a joystick and I don't recognize the PCB.

Also check out flim-flam. PM sent
Yes, found this : http://www.classicarcadegaming.com/forums/index.php?topic=776.0
It looks close from a conceptual perspective. Will see if there are schematics.

Cool, lots of responses, great people here !

Schematics also do make progress:
http://www.andysarcade.de/projects_files/slam_1011_3701_schematic.pdf
http://www.andysarcade.de/projects_files/slam_1011_3700_schematic.pdf
 
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The lower four digit # is likely to be the date of manufacture as mentioned. Maybe a 7402. The 54 being the military version since it is ceramic. This is just a guess though. If you can remove it intact and it is still functional then it can be identified with a tester such as a Leaper-1 or an Eprom programmer that has a built in test function for TTL.
 
The lower four digit # is likely to be the date of manufacture as mentioned. Maybe a 7402. The 54 being the military version since it is ceramic. This is just a guess though. If you can remove it intact and it is still functional then it can be identified with a tester such as a Leaper-1 or an Eprom programmer that has a built in test function for TTL.

Yeah, you maybe right with the date of manufacture. The schematics I have drawn from th actual board is suggesting a sort of Quad Timer, no TTL as far as I can say. There are a couple of 7402's on the board that are clearly identifiable as such.
 
Hi,

please allow a bump. Still looking for this chip's details.

Is anyone recognizing the Chip in the middle of the small picture " 542 7529" ?
Could be also known as a 4 Channel analog to PWM (pulse width modulation) .


Thanks again
 

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Got it working :)

Today I managed to get one of two PCB sets working. All four paddles have now collision detection. So now lets take a look at the monitor. As already noticed, the HV transformer had the clamp for the ferrite core broken, so the two halves of the ferrite were loose. In the meantime I had bought 4 brass rods from EBAY, 2.5mm diameter and 300mm long and made a new clamp from that by bending it into a U-shape and adding two M2.5mm threads at the ends. The monitor also supplies +5V to the PCB's, which was flat at 4.6V and could not be adjusted. After some measuring I replaced what was a µA741 Op-Amp (Motorola designation was T3F -> weird!). Lastly a pot on the Audio Amp was defective, easy one.

Moved the whole stuff upstairs and put all back into the Cab, after giving it a good cleaning. To be done :

* Paint the large foot (cast iron)
* Add a lock
* Replace the turn knob for game difficulty selection
* And : Do the second machine :)

For all who are interested, I have uploaded a video of the repaired/working game:
http://www.andysarcade.de/projects_files/slam_working.mpg

And here once again my SLAM (Mirco Games) project page:
http://www.andysarcade.de/projects_slam.html
 

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the game and unknown chips intrigued me, so i was still havin a look thru the partial schematics - good to hear u got it working!

just out of interest,
- are the unknown chips working then ?
- whaddidyahavtadotofixtheboards ?

otherwise i was going to suggest trying to work backwards to determine what signals the chip should be outputting based on the output circuitry ... kinda redundant now at least you got agood one for reference !

Cheers, Andy :D
 
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@andykmv
- Yes the unknown chips are all working( 3 on the board ). Their output is 4times a fixed frequency square wave with a variation in duty cycle, based on the 4 input voltages ( so four channels in one chip).
- most of the defective TTL chips (5) I could identify with his guy :
http://pdp-8.org/tools.html#HP_10529A_Logic_Comparator
Still the collision detection wasn't working even if all chips found to be ok with the comparator. Honestly I was doing a mass replacement then, "one column of chips" at a time. The second column brough the collision detection back: 16 chips, not too bad.
 
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