Space Duel, Black Widow, Gravatar.....Dedicated Atari games with Amplifones in them

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Space Duel, Black Widow, Gravatar.....Dedicated Atari games with Amplifones in them

Hello all,
In a recent post, I learned something that I was unaware of. Atari modified Major Havoc pcboards to operate faster than their conversion counterparts. The reason was apparently that the Amplifones could handle the extra speed (since they were MED RESolution) and had a faster refresh rate (I think?) The post that talked about his was somewhere in here:
http://forums.arcade-museum.com/showthread.php?t=261947

Anyways, this got me thinking.....Maybe Atari modified other PCBs to run at faster rates when they had Amplifones in them from the factory. From what the other post said, they did this by using faster crystals...and jumpering some of the chips (at least on Mj. Havoc.) I think ded. Mj. Havocs had Amps in them as did Quantums. So it stands to reason that the boards would probably have the faster crystals and maybe the mods.

My point. I have a Space Duel project that is missing the original pcb. Long story....don't ask. But I would assume Atari had occaisonally put Amps in other games like Black Widow, Gravitar, maybe Tempest...whatever. So my first question, is does anyone have any of these games with dedicated Amplifone monitors in them. And my second question is could you take some pics of the pcb and maybe make note of the Crystal speeds. If there is a difference, I would suspect jumper wires and crystals to be be faster (higher Mhz). And maybe some Vector/Atari guru already has the answer to this. Just thought I would throw it out there since the thought of a Space Duel that not only looks better, but runs faster sounds like a worthwhile project. Conversely any repro pcb that should use an Amplifone (i.e. the new run of Quantum PCBs) might not look their best running on a Wells 6100 without the slower crystals.

Then again, maybe its Sat. night...and I'm board, and completely off the mark on this one. Just thought it was worth a conversation.
 
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I'm not an expert, but to me it would make more sense to be the opposite: Major Havoc was designed on an amp and then tweaked to work better on a wg6100 when it was decided that conversion kits were to be made.

My understanding is that Tempest never came from the factory with an Amplifone, but all the others have at some point or another.
 
Not if you consider that the Wells6100 was the standard when Tempest came out in '80 since it was the only color vector. At least till Sega brought out Eliminator and Space Fury in '81 using the Electrohome G08. And that proved less than effective. Atari decided to manufacture their own improved version later in a med res monitor and had to redesign a great deal of the monitors to get around the patents WG held. And ultimately, they did design and build a better monitor with the fatal flaw of using bad flybacks (or flybacks rendered defective by one catastrophic accident). Major Havoc came out in '83 and surely had at least a year in development. Design team probably designed the first boards for the Wells. Of course, it does make more sense to redesign the PCB for the newer circuit....But maybe not as cost effective as just adding 2 different crystals and 5 or so jumpers. Quantum on the other hand supposedly came out in'82. Not sure if they were all Amps or part amp and part Wells. But I think "82 was probably were the monitors went from Wells to Amps. Star Wars was '83 and it was all Amps to the best of my knowledge. They were converted in mass when the Amps started dying. Star Wars was a huge money maker and who wouldn't remove a Wells from a Gravitar to save a Star Wars?

Tempest probably never came out in an Amp. But a lot of games were manufactured in numerous years. So it is conceivable that a Tempest was manufactured in '82 that may have had an Amp in it. Doubtful...but worth asking if anyone has one.

I'm not an expert, but to me it would make more sense to be the opposite: Major Havoc was designed on an amp and then tweaked to work better on a wg6100 when it was decided that conversion kits were to be made.

My understanding is that Tempest never came from the factory with an Amplifone, but all the others have at some point or another.
 
Major Havoc came out in '83 and surely had at least a year in development. Design team probably designed the first boards for the Wells. Of course, it does make more sense to redesign the PCB for the newer circuit.

By that logic, Star Wars should have been designed for the WG6100 and then modified also. Not sure if there's any evidence of that.

To me it still makes more sense that Atari switched to the pin compatible Amp during the Gravitar/Black Widow run and that the games that came after were designed for the Amp. After all, the amp switch didn't happen over night and the dev guys would have know it was coming.

But I'm speculating based on MY minimal knowledge so I certainly don't claim that I'm right.
 
Hello all,
In a recent post, I learned something that I was unaware of. Atari modified Major Havoc pcboards to operate faster than their conversion counterparts. The reason was apparently that the Amplifones could handle the extra speed (since they were MED RESolution) and had a faster refresh rate (I think?) The post that talked about his was somewhere in here:
http://forums.arcade-museum.com/showthread.php?t=261947

Anyways, this got me thinking.....Maybe Atari modified other PCBs to run at faster rates when they had Amplifones in them from the factory. From what the other post said, they did this by using faster crystals...and jumpering some of the chips (at least on Mj. Havoc.) I think ded. Mj. Havocs had Amps in them as did Quantums. So it stands to reason that the boards would probably have the faster crystals and maybe the mods.

My point. I have a Space Duel project that is missing the original pcb. Long story....don't ask. But I would assume Atari had occaisonally put Amps in other games like Black Widow, Gravitar, maybe Tempest...whatever. So my first question, is does anyone have any of these games with dedicated Amplifone monitors in them. And my second question is could you take some pics of the pcb and maybe make note of the Crystal speeds. If there is a difference, I would suspect jumper wires and crystals to be be faster (higher Mhz). And maybe some Vector/Atari guru already has the answer to this. Just thought I would throw it out there since the thought of a Space Duel that not only looks better, but runs faster sounds like a worthwhile project. Conversely any repro pcb that should use an Amplifone (i.e. the new run of Quantum PCBs) might not look their best running on a Wells 6100 without the slower crystals.

Then again, maybe its Sat. night...and I board, and completely off the mark on this one. Just thought it was worth a conversation.

I'll take a picture of my black widow board tomorrow
 
Amplifones don't run any "faster". The deflection circuit is very similar,and use the same transistors. Plus vector monitors run at what ever the input is. I think the amplifone Hv may have a bit more capacity though.
 

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My Gravitar has an Amplifone from the factory... I really doubt there is any change, but I'll snap a pic when I get a chance. I'm guessing if MH slowed down the xtals for conversions, it's because it was developed for the Amp, and looked like crap on the 6100 because it couldn't handle the faster slew rate (has nothing to do with the "med res" tube itself). So, the easiest solution was to slow everything down a little bit (I doubt it was the other way, since it wouldn't be worth the effort to speed the whole game up a little bit for a higher frame rate on the Amp, unless it was unacceptably slow).

If you look at the ZVG, it has adjustable drawing speeds... the G05, WG2000, G08 and amplifone all draw at 15us/in, but the setting for the WG6100 is 30us/in. If you run a 6100 at Amp speed, it looks bad. Like mcandrewsoun said... a vector monitor doesn't run "faster" than another... they run at whatever speed the input drives them at (there's no 15KHz CGA, 25KHz EGA type thing). But some monitors can accurately draw faster than others.

DogP
 
That does seem to suggest that the 6100 slew rate is less. The significant difference between the 6100 and all the rest is that the 6100 has a regulated supply in the deflection circuit. One of the potential upgrade is to bypass the regulator circuit. I haven't done circuit analysis in a long time but it looks like the power supply transistors are in series with the output devices.. This would increase the output impedance and maybe affect the slew rate. If nothing else you'd have two devices switching 34v. I'm guessing the differential inputs would compensate for power supply issues, so regulation may be overkill in the deflection circuit. So bypass the reguator circuit build a +-24v reguator for the Hv and I bet you'd get the 6100 speed up.
 
I've had a SW cockpit with an amp and an upright with a 6100 next to it. There is no speed/refresh difference... at least with that game.
 
I'd love to know which tubes are in the amplifone loaded sd/bw/grav/Mh..

You'd think there would have to be a significant crystal change to slow the vectors down...also most likely this would affect how many times per second the screen is refreshed as speed will affect how long it takes to draw a screen.
 
In all honesty, I'm no tech, but I did want to understand what was going on here. Here is the source info in the other post that led to this post.

Dedicated machines do indeed run faster. Taken from ionpool :

"Major havoc boardsets that were meant to run in a Tempest Conversion (using a Wells-Gardner 6101 monitor instead of an Amplifone) had slower crystals in them so that the monitor could handle the drawing rate.

Original boards had a 12.0 and 10MHz while the conversion boards replaced them with a 10.0 and 8.9MHz respectively.

You can tell a 'conversion' board just by playing it because the sounds are about 3 steps down in tone, they also play much slower, which is probably good since you just can't do as much with the tempest spinner compared to a nice roller!"

The last part of that quote is (erroneous) opinion. Both controllers are 2-way optical. A spinner coupled with a properly outfitted conversion PCB (with R186 in place) would actually respond 33% faster on the 10% slower drawing 6100, due to the variance of resistance on the optical boards between the 2 controllers.

I know there's a jumper wire on the conversion boards that isn't there on the dedicated version. Not sure of purpose though.

Here are pics of my Tollian Web board you can see the different jumpers on the lower part of the board,the upper part of the board where the adjusting pots are have no jumper wires like the conversion board does.
 

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So upon rereading these, I notice that the jumper wires are on the Conversion boards instead of the dedicated. So I got that backwards. It looks like the slower crystals and the jumper wires were actually slowing down dedicated pcbs so they could be used in cabs with wells monitors in them. Which makes me wonder if you removed the wires and installed faster crystals, could you make the conversion PCBs run faster....if you were going to use an Amplifone crystal in it. And conversely, could tempest PCBs be made to run faster with faster crystals and maybe the addition of an Amplifone. But if the pcbs are all outputting the same speed, I'm still left trying to figure out what's going on here. I'll reread this whole post later......when I have more time and again try to wrap my mind around what's going on. But thanks for the replies so far.
 
So upon rereading these, I notice that the jumper wires are on the Conversion boards instead of the dedicated. So I got that backwards. It looks like the slower crystals and the jumper wires were actually slowing down dedicated pcbs so they could be used in cabs with wells monitors in them. Which makes me wonder if you removed the wires and installed faster crystals, could you make the conversion PCBs run faster....if you were going to use an Amplifone crystal in it. And conversely, could tempest PCBs be made to run faster with faster crystals and maybe the addition of an Amplifone. But if the pcbs are all outputting the same speed, I'm still left trying to figure out what's going on here. I'll reread this whole post later......when I have more time and again try to wrap my mind around what's going on. But thanks for the replies so far.

I am guessing yes, you can convert them back. That was my intent on a few of the conversion boards I have. I don't have the Space Duel/Tempest conversion boards to go with them so I figured I would make them available to people that want to make a dedicated Havoc repro. I plan to test them in my Havoc cab and will post results. Not going to happen soon.....have to get some Tempest boards fixed first.
 
As I understand it, the Amplifones in the dedicated Major Havocs could keep up with the game, but the conversion kit going into cabinets with WG6100s needed the drawing to be slowed down, so the crystals were swapped. Second, the raw signals for X and Y out were re-routed on the main PCB to some unused pins on the edge connector. The conversion board then took them and applied pincushion correction and X linearity/size/centering adjustments before passing to the game harness.

I put an Amp in my Space Duel and it looks great! Will be playing BW, Gravitar, MH, SD... and Quantum once the panels come and the second repro boards are made. Woohoo!
 
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I've had a SW cockpit with an amp and an upright with a 6100 next to it. There is no speed/refresh difference... at least with that game.
Yep, there wouldn't be, because (AFAIK) the uprights all had Amps as well... so there never would have been a factory mod to slow it down for the 6100.

You'd think there would have to be a significant crystal change to slow the vectors down...also most likely this would affect how many times per second the screen is refreshed as speed will affect how long it takes to draw a screen.
That's exactly what's going on... they dropped the clock speed by about 1/6th, so everything runs slower... audio, video draw speed, frame rate, etc.

So upon rereading these, I notice that the jumper wires are on the Conversion boards instead of the dedicated. So I got that backwards. It looks like the slower crystals and the jumper wires were actually slowing down dedicated pcbs so they could be used in cabs with wells monitors in them. Which makes me wonder if you removed the wires and installed faster crystals, could you make the conversion PCBs run faster....if you were going to use an Amplifone crystal in it. And conversely, could tempest PCBs be made to run faster with faster crystals and maybe the addition of an Amplifone. But if the pcbs are all outputting the same speed, I'm still left trying to figure out what's going on here.
That makes sense the that conversions had the mods, and I'm sure you could undo the mods to get a regular Amp ready board. You could possibly run a faster clock in Tempest and other games to get faster draw speeds and refresh... but then the game itself will be running faster, making it harder. It's also very possible that the hardware wouldn't handle running any faster... if the CPU is a 4MHz CPU running at 4MHz, you can install a 3MHz crystal, but you can't (reliably) install a 5MHz crystal.

DogP
 
I would love to find a Widow, Gravitar, or Space Duel with Amp in it!!

I got lucky and finally found a Black Widow with an Amp!!!

Ill take a look at the board in my black widow and see what the crystals are.
 

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Ok,Since all Black widow games were just conversions from gravitar,the board is a gravitar board.Which if im right,original gravitars had amps in them(i think).The crystal on the black widow board and the gravitar board i looked at(I have both) has a 12.096 crystal on them and no jumpers at all.I also have a black widow running with a 6100 that i put in a Tempest cab,pics posted.(Yes it has a rastan cp overlay and a major havoc marque.Lol....)
The black widow runs great on the 6100 as it does on the Amp.
 

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