Dreams destroyed by Battlezone

discostu

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Its taken me 30 years but I finally bought an arcade, Battlezone, it worked fine when I picked it up and fine for the next 22 hours then suddenly the vector graphics wen't bezerk. I checked the interconnects going to and from the pc boards, wiggled and tapped on all the IC's, tried adjusting the X and Y pots on the generator board but the problem persists. So the game plays fine its just that all the images are really crooked and the moving images look like a pile of disembodied vectors moving around on the screen. The self test starts with a quick beep and thats it, grid is pretty distorted as well, the disappointment has me pretty bummed : (
 
I can see why you are bummed, but hang in there :)

Sounds like ram or a rom socket to me

Have you re-seated the roms after carefully cleaning the legs?

Keep bumping and someone will help
 
get a high score save kit - elmininates the roms and the socket issue.

mh

That's an excellent idea; I did that when fixing my DOA BZ PCB. Eliminates several potential issues, and provide HS saving to boot :) I think arcadeshop and mikesarcade sells them, or perhaps directly from Scott Brasington?

A couple of other basic things to check/try/do are:

1) Ensure you have a nice 5.0-5.1 VDC at the PCB. Adjust and/or re-pin connectors if required. Having low voltage can cause wacky things to happen (but I'd guess more likely to cause resets than wonky vectors...) In any case, it's easy to check and adjust.

2) Carefully and fully check your interconnect wiring! This should be item #1. Both the headers on the boards, and the wires themselves, are prone to problems. The solder joints at the headers (particularly those near the ends) crack. This is difficult to see without magnification. The wires were thin and break at the crimp-on pins. Bad connection to the Aux board can cause wacky vectors, as it's responsible to the 3D vector math. Personally, I'd re-solder all of the joints at the interconnect headers, and re-build (all new pins) the connectors before doing anything else on a BZ board (aside from careful visual inspection).

3) One or more beeps in test mode (if the portion of the ROM code with test mode is good, and the CPU can run it properly...) indicate a bad RAM chip. Get the manual (http://arcarc.xmission.com/PDF_Arcade_Atari_Kee/Battlezone/Battlezone_TM-156_3rd_Printing.pdf) and check out page 15 (15 in the PDF doc; page 7 as printed on the page). I had a couple of bad RAMs in mine, and the beep codes helped me find them. I was lucky, and they were the latter portion of the vector RAM, so my bad RAM only manifested itself when a lot of things were being drawn on the screen. The RAMs are 2114s, and I think Bob Roberts has them for a couple bucks a pop. Unless they've already been replaced, they're likely not socketed. You'd need to desolder or cut out the bad RAM, solder in a socket, then pop in the new RAM.


BZ is very cool, and I can understand your disappointment as it was working when you got it. The good news it that the PCB can be fixed. The only question is if it's something you want to do, or if you want to send it out for repair. Unless you feel good about your soldering skills, you might strongly consider finding a repair vendor--beyond building a new interconnect cable and installing a Braze HS kit, there aren't many repairs that can be affected w/o soldering.
 
Hey thanks guys! I appreciate all the feedback! Yeah I have always put the arcade on the back burner for so many years, I finally went nuts and decided I must have a goddamn arcade now! As usual I now look like a complete fool as my latest venture just sits there looking like a huge expensive paper weight, my fiancée has been decent about the whole thing but we could really do without any more projects, our 120 year old house is just coming to pieces all around us. Any thoughts on whether it might be a problem with the analog or digital stage? I'm not very digital savvy but I'm a hi fi geek so basic analog circuits are not beyond my comprehension. Looks like 3 DACs (X,Y,Z) output into an op amp (buffer) then switching IC before being sent to the monitor, sound right?.
 
Its taken me 30 years but I finally bought an arcade, Battlezone, it worked fine when I picked it up and fine for the next 22 hours then suddenly the vector graphics wen't bezerk. I checked the interconnects going to and from the pc boards, wiggled and tapped on all the IC's, tried adjusting the X and Y pots on the generator board but the problem persists. So the game plays fine its just that all the images are really crooked and the moving images look like a pile of disembodied vectors moving around on the screen. The self test starts with a quick beep and thats it, grid is pretty distorted as well, the disappointment has me pretty bummed : (

Welcome to the hobby! You unfortunately, picked a real picky/fussy game to start out with.

No fear, there are people who are pretty good with these things.

Turn on the selftest button then take a pic of what the screen does. You should get some letters/numbers somewhere.

Installing a battlezone high score save kit might help, it bypasses all the original roms.
http://www.mikesarcade.com/cgi-bin/store.pl?sku=HSBZONE

I dont remember if its on the main board or the aux board, but theres some sockets that get flakey and cause mathbox issues etc.

Wish i could be of mroe help. I used to own a bz and after doing it all i gave up lol it worked when it wanted to. Vector games tend to be very fussy.
 
I do not have a pin out for the main pcb, where should I be metering for voltage? The last couple of self tests did not have any beeps or letters, screen looks crooked and moving vectors still look crazy though (game still plays fine, just looks like crap). Removed socketed IC's and harness connecting two boards, solder joints look fine (I belive the main board was rebuilt a few years back). I also have an annoying hum coming from the speakers, 60hz perhaps.
 
I do not have a pin out for the main pcb, where should I be metering for voltage? The last couple of self tests did not have any beeps or letters, screen looks crooked and moving vectors still look crazy though (game still plays fine, just looks like crap). Removed socketed IC's and harness connecting two boards, solder joints look fine (I belive the main board was rebuilt a few years back). I also have an annoying hum coming from the speakers, 60hz perhaps.

The manuals are here:

http://arcarc.xmission.com/PDF_Arcade_Atari_Kee/Battlezone/
 

As are the schematics, and a few other things.

discostu, the "DP" files (drawing package) are the ones with the stuff you're looking for. The 1st, 2nd, 3rd are printings. I go with the latest printing unless I know my version of a PCB is better represented by an earlier printing. Usually there's more/corrected information on the later printings. The "01" and "02" are sheet numbers; these were presumably printed on 2 sheets. And the "A" and "B" are the front and back of each sheet. I think you'll find the wiring diagram has the information you want, it's on sheet 1 side A.

1B is all signature analysis stuff (only usefuly if you have a signature analyzer). And 2 A&B are where all the good jucy stuff is.

All that said, the easiest place to check most of the important voltages on Atari boards are the "test points". Look closely at the board and you'll find maybe a dozen little loops soldered to the board, each with a label (that corresponds to indicated TPs in the schems). There will be one for +5VDC and likely several for GND (any one will do). http://www.elektronforge.com/Images/Atari_TP.jpg

Wow, I just realized that image came from a really nice page by the elektron forge guy: http://www.elektronforge.com/AdjustAtariPS.htm
 
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Thanx for the great info! Tested each of the test points and got mostly good voltages, there is a 36vac test point that produced only 18vac on the regulator/audio board along with an unregulated 10.3vdc point that was cranking out 11.5v, a -22 & +22 vdc that were both at 23v and finally a +5vdc high up on the auxillliary board near the right upper corner that had only 4.75v. I also discovered r29 on the regulator/audio board is fried, probably recently as I now no longer have any video just the spot killer.
 
Tested each of the test points and got mostly good voltages, there is a 36vac test point that produced only 18vac on the regulator/audio board along with an unregulated 10.3vdc point that was cranking out 11.5v, a -22 & +22 vdc that were both at 23v and finally a +5vdc high up on the auxillliary board near the right upper corner that had only 4.75v. I also discovered r29 on the regulator/audio board is fried, probably recently as I now no longer have any video just the spot killer.

I don't have a board in front of me, but the 36VAC should only measure that across the two sides of that AC line. Transformer is center-tapped, and the CT is grounded, so each leg of the AC will only measure about half of that voltage relative to GND. There should be two TPs for 36VAC; one connected to J9p4, another tp J9p5. Have to measure AC across these two to expect the full 36.

Unregulated "10.3" at 11.4 doesn't sound like a big deal. Hey... it's unregulated :p I think it's actually an INPUT to the A/R board, not an output. It's used to generate the regulated 5V, and power the audio amp. It's rectified in the power "brick," and filtered by the Big Blue" capacitor. Which reminds me; if your Big Blue appears original, you might check the AC content on the 10.3 unreg line. I forget how much is generally considered "OK", but replacements of those caps are widely performed.

The +/-22VDC are used by PCB video output amps, as well as the audio amps on the aux board. I just realized that the "3rd printing" on arcarc.xmission.com is missing sheet #3; get those from the 2nd printing... they include the aux board. Anyhow, these voltages are good...

4.75 is at the low edge of the specs for 74LS ICs. Power comes to the aux board via a few pins in the edge connector. Check/replace the pins in the housing, and check/clean the PCB edge traces.

Regarding the fried R29... This is a symptom of the +5V "sense" circuit either "going bad" or "doing its job." There has been a long-running Holy War regarding this matter. There are two camps: those who say "that's the way it was designed to work; it's an indication that there are bad connections between the AR board and the PCB, and they should be fixed." and those who say "that's suipid, I'm just going to do the sense-mod and be done with it." Personally, I don't perform the so-called "sense-mod" on my Ataris. (But I do not wish to re-ignite a flame war on the topic). Do some googling with the terms atari, R29, sense mod, etc. and you'll find plenty to read. In any case, if your R29 burned, you had a lot of current flowing, so you should check (again) the molex power connectors on the AR board (both ends) and the edge connectors at the PCBs (both ends) for burns. What this tells me, is that at least one of the pins (in the sense line) wasn't making good contact, and that you might consider rebuilding your edge connectors. A good crimping tool isn't very expensive, and the crimp-on terminals are cheap too. I buy things like that from Ed at Great Plains Electronics: http://www.greatplainselectronics.com/Category-35.asp , http://www.greatplainselectronics.com/Category-53.asp Bob Roberts also sells this sort of thing, as well as "kits" of parts for fixing/rebuilding the AR boards: http://www.therealbobroberts.net/ar2.jpg
 
Thanks Darren, I took the measurements late last night while cleaning the kitchen and I feel like a fool, yes the 36v..AC should be measured at both outputs from the trafo. R29 probably went up in smoke while my right elbow was massaging the connector for the PCB.I appreciate all the excellent information so far, it would have taken me ages to accumulate this stuff on my own, thanks again.
 
I replaced some crusty op amps in the analog section of the pcb, no luck though. Got the A/R -02 working again and voltages all check out ok but I'm still not getting any signal to the monitor (red led). The scope hooked up to x & y out just shows rock solid 12 and 14vdc present but nothing else. The op amps and switching IC's are rather hot, not sure what to do.
 
I replaced some crusty op amps in the analog section of the pcb, no luck though. Got the A/R -02 working again and voltages all check out ok but I'm still not getting any signal to the monitor (red led). The scope hooked up to x & y out just shows rock solid 12 and 14vdc present but nothing else. The op amps and switching IC's are rather hot, not sure what to do.

If you get too frustrated, pm road.runner here and let him fix the boards. :)
 
Thanx for the great info! Tested each of the test points and got mostly good voltages, there is a 36vac test point that produced only 18vac on the regulator/audio board along with an unregulated 10.3vdc point that was cranking out 11.5v, a -22 & +22 vdc that were both at 23v and finally a +5vdc high up on the auxillliary board near the right upper corner that had only 4.75v. I also discovered r29 on the regulator/audio board is fried, probably recently as I now no longer have any video just the spot killer.

18vac means that you measured it incorrectly and it is exactly half of what is actually there. AC does not measure to ground like DC. Pull J5 from the power brick and measure the AC in pins 8 & 9 and you will get 36vac.

If R29 is fried, you will NOT have the proper +5vdc to run the game. Rebuild the A/R II and clean the fingers on the boardset where the edge connectors go.
 
....If R29 is fried, you will NOT have the proper +5vdc to run the game. ...

as prev mentioned 4.75v is the lower margin of reliable (predicatable) operation for TTL ICs. but if some ics that do the vector stuff are out of spec or if there are voltage losses between the test point and the ics that do the vector stuff, could explain the crazy display. as dokert says, check the resistor, rebuild the arii which should get your 5v rail up to a more acceptable 4.9-5.1v at the test points.

good luck - its a great game!
 
The A/RII kit has already been ordered from Bob Roberts, as has a replacement for big blue, high score saver and new 44 oin connectors are also on the way. I already replaced r29 and cleaned most of the finger connectors on the boards, re-flowed some solders and replaced the tl082 op amps on the vector board (the old ones were oozing slightly, yikes!). I'm a little concerned something else may have gone up in smoke around the time r29 burned out from me bumping the connector on the PCB as there was an image and gameplay before and now I'm just left with blind gameplay (and the hum from my old blue cap). I noticed something, one of my sense test points has voltage (+5) while the other does not, should that be?

As usual, thanks guys!

Patrick
 
I noticed something, one of my sense test points has voltage (+5) while the other does not, should that be?

I'm not sure which two sense test points to which you are refer. Both on the AR board? I haven't got one in front of me (nor do I know which rev of the board you have), but there may be "SENSE+" and "SENSE-" lines/test points. If so, you'd only expect +5 on the SENSE+ line, and 0V on the SENSE- (both relative to GND).

Where are you making the sense measurements (and with what connected)?
 
R29 probably went up in smoke while my right elbow was massaging the connector for the PCB.

What R29 is telling you when it burns up is that your connectors have issues. It burns (of course) because there is too much current going through it. In "normal" operation, very little (almost no) current should go through R29, as the "+5 REG" and "+SENSE" lines are connected together at the PCB. This should bring the voltage on both lines to more-or-less equal, which would mean next to no current in R29. The only thing that causes current through R29 is a difference in voltage across it. This tends to happen when the connectors go bad, and begin to develop a lot of resistance, which leads to a lot of voltage drop across the connection (and resulting heat). This also leads to a difference between the supply +5 and what comes back from the PCB on the +SENSE line, which means current through R29.

In any case, when R29 burns, in addition to replacing it, one should look for bad connections both at the AR board connector pins (J7 & P7), and at the PCB edge connector pins, because these are what caused R29 to burn.
 
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