Help: Major Havoc PCB Identification

fassaette

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I have a Major Havoc in a Tempest cabinet. I always assumed it was a conversion board. However, after taking a closer look at the PCB, I am starting to think it is a dedicated. Please take a look and let me know. Thanks!

A few observations:
Y1 = FOX100 10.000
Y2 = 12.096 NDK .38
Quad Pokey Eliminator Board
"Tollian Web" and Rev1 markings on board

The board is currently running in a Tempest cabinet with a 6100 monitor.

If you have any additional questions or need any other pics, just let me know.
 

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Here are a few more pics.

Also, I would really like to speed up the character movement. Character movement requires an excessive amount of rolling to move (note: reproduction roller). I tried hooking up the Tempest spinner but that yields no movement. Very odd.....

Again, any ideas???
 

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Sorry, just a few more pics.
 

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It's very easy to tell by the edge connector on the upper left.

If it is 12 positions, it is a conversion
if it is 10 positions, it is a dedicated.

The extra two pins provide x&y out prior to scaling and centering. the pre-XY is used for the pin cushion correction.

the dedicated used 10 an 12 and play faster. The conversion used 9.86 and 8 and played slower. The 8mhz is for the vector generator, meaning the conversion on an amplifone monitor will have more flicker...
 
Added pics of the edge connector. I counted 12. So, it's a conversion?

I am still confused. My Y1 is 12 and my Y2 is 10. How is that possible?
 

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I am still confused. My Y1 is 12 and my Y2 is 10. How is that possible?

Y1 is for the vector generator. It may be that the crystal change to 9.816(cpu) and 8(vector) was done later when they realized the 6100 in the conversions couldn't keep up.
 
Y1 is for the vector generator. It may be that the crystal change to 9.816(cpu) and 8(vector) was done later when they realized the 6100 in the conversions couldn't keep up.

That would make sense if my Y1 was 12 and my Y2 was 10. However, mine are opposite. The solder side of the board suggests someone has done some repair work. Is it possible they swapped the chips???

Note: The first picture is of Y1 (left two pins) and the second picture is of Y2 (right two pins).
 

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Sorry I didn't have the schematic in front of me for my previous post...

Y1 is the CPU clock and should be 10MHz for dedicated and 9.xxxMHz (I think mine is 9.216) for a conversion.
Y2 is the vector clock and should be 12MHz for dedicated and 8MHz for conversion.
 
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Sorry I didn't have the schematic in front of me for my previous post...

Y1 is the CPU clock and should be 10MHz for dedicated and 9.xxxMHz (I think mine is 9.216) for a conversion.
Y2 is the vector clock and should be 12MHz for dedicated and 8MHz for conversion.

The slowdown in the vector generator matters for the 6100 vs amplifone.

The slowdown in the CPU clock is pretty much irrelevant -- they only scaled it back to make sure the CPU doesn't watchdog while waiting for the 1/3 slower vector generator to finish drawing complex screens.

Would be fun to replace the vector crystal with a programmable VCO and experiment with different frequencies on a 6100 to see how fast you can push it before it "can't keep up".
 
I believe all boards marked Tolian Web are dedicated PCBs. Your crystals are dedicated.

In addition, the S/N tag on a dedicated will start with UR, for the conversions they start with CK or CB.

I believe that all the dedicates originally had quad pokey chips, but if it failed, it would not be surprising to find a quad pokey eliminator which I believe most if not all the conversion boards came with.

Either board (conversion or dedicated), is not hard to alter to be the other configuration.

As for the spinner, there are versions of the spinner with a different value resistor... MH requires a particular one. If the resistor is wrong, you need to change it. If that doesn't give you motion, then it could be the opto boards or he main PCB. See service bulletin http://www.ionpool.net/arcade/atari_docs/major-havoc-bulletin-51884.pdf
 
"Tollian Web" denotes an original dedicated PCB. Someone converted it so it could play in your Tempest cabinet. Another indicator would be the serial sticker if it still has one, not that it is needed for identification as Tollian is sufficient. As mentioned, it would start with UR as opposed to CK or CB.
 
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It's very easy to tell by the edge connector on the upper left.

If it is 12 positions, it is a conversion
if it is 10 positions, it is a dedicated.

The extra two pins provide x&y out prior to scaling and centering. the pre-XY is used for the pin cushion correction.

the dedicated used 10 an 12 and play faster. The conversion used 9.86 and 8 and played slower. The 8mhz is for the vector generator, meaning the conversion on an amplifone monitor will have more flicker...

This is incorrect.
 
I found some additional information (see link below). I am now convinced that my PCB is a dedicated Major Havoc that has been converted to play in a Tempest machine. That said, I am still looking for some help.

1) I have a 10.000 MHz crystal at Y1 and a 12.086 MHz crystal at Y2. Are these values acceptable if I am running a repro track roller and a 6100 monitor?

2) Why does my track roller require excessive rolling to move the character? My PCB does not have R186 or the solder pads to adjust the speed.

3) Why can't I get the Tempest spinner to work? Plugging it in yields no movement when spinning in either direction.

Thanks again!




Useful Major Havoc Link:
http://forums.arcade-museum.com/showthread.php?t=350749&page=3
 
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I am now convinced that my PCB is a dedicated Major Havoc that has been converted to play in a Tempest machine.
Agreed. But only sorta converted... they added the critical jumpers to get video through the MH-Tempest adapter board but did not change the crystals and could not add R186.

1) I have a 10.000 MHz crystal at Y1 and a 12.086 MHz crystal at Y2. Are these values acceptable if I am running a repro track roller and a 6100 monitor?

I think so. If you watched that video I made, the big difference is because of the dot pitch of the tubes. I notice the WG6100 not 'keeping up' much more in Star Wars (on the Red Five Flight Instructions screen full of text) but I think MH looks fine on a WG. Whether the faster drawing puts any stress on the circuitry of the 6100 is another question.

2) Why does my track roller require excessive rolling to move the character? My PCB does not have R186 or the solder pads to adjust the speed.

Nope, the dedicated boards simply do not have a spot for R186. You might jury-rig something, or I would trade your board for my 100% working, bona-fide conversion board since I'm in the exact opposite of your situation.

3) Why can't I get the Tempest spinner to work? Plugging it in yields no movement when spinning in either direction.

Could be your MH board, the adapter board, your Tempest wiring harness or the Tempest spinner 'opto' board. If you are getting a roller controller, that will eliminate the spinner question. Harness is a low probability (but check the four wires at the connector right at the spinner). I'd include test/repair of your MH-Tempest adapter board in my trade offer.
 
Here is a pic of the chips in row 2 (per the PM request). If anyone needs any other pics, just let me know.
 

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I just watched this Todd Tuckey video. (start at 1:20)

https://www.youtube.com/watch?v=gNf4r7qrFTc

He explains that the bottom harness plug needs to be flipped for the Tempest control panel to work. That explains why my Tempest control panel wasn't working. I didn't have the plug flipped. I am now educated.

I guess the reproduction track roller that I am using has the "flip" built into it??? It works fine without having to flip the bottom harness plug.

EDIT: Flipping the bottom plug did NOT work. Game plays perfectly fine with the track roller (I just thought the rolling seemed excessive). Done mucking with it, time to play. :)
 
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