My new Berzerk

airlair

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Donor 2011
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I can tell this is going to be an interesting one to work on. When I first got it the LED on the ZPU would beep three times when I fired it up. I spent yesterday removing all interconnect ribbons and cleaning the pins on the board then replacing the interconnect ribbons. After that, I removed, cleaned, and replaced all ROMS, the Z80, and everyother removable chip on the ZPU. Now if I fire it up, I get one of two things. Either the ZPU LED will stay on, or it will beep continously.

As far as the monitor it is complete but dead. There is not even a neckglow, but being rather inexperienced I have no idea if this is related to the board issues. I think I'm going to need some help with this one.
 
I can tell this is going to be an interesting one to work on. When I first got it the LED on the ZPU would beep three times when I fired it up. I spent yesterday removing all interconnect ribbons and cleaning the pins on the board then replacing the interconnect ribbons. After that, I removed, cleaned, and replaced all ROMS, the Z80, and everyother removable chip on the ZPU. Now if I fire it up, I get one of two things. Either the ZPU LED will stay on, or it will beep continously.

As far as the monitor it is complete but dead. There is not even a neckglow, but being rather inexperienced I have no idea if this is related to the board issues. I think I'm going to need some help with this one.

Monitor issue is separate of the board issues. The monitor is most likely a WG 4600 or an Electrohome G07. If a 46, capping all the boards is a PITA, but do-able. If it is a G07, you'll need to rebuild the chassis, caps, fuses, flyback and HOT.

As for your board issue, you need to first check your ZPU Board (upper left) for battery acid damage. There will be an on-board battery the size of a AA, unless it's been removed. There will be corroded diodes, chip legs, etc. You may also have some issues at the CPU or PSU. You need to also check the voltages coming out of the PSU (power supply). You can contact member seinologist to see if he may be able to help you fix them. He is a Berzerk master, but seems to be getting out of the hobby so best to catch him soon.
 
Monitor issue is separate of the board issues. The monitor is most likely a WG 4600 or an Electrohome G07. If a 46, capping all the boards is a PITA, but do-able. If it is a G07, you'll need to rebuild the chassis, caps, fuses, flyback and HOT.

As for your board issue, you need to first check your ZPU Board (upper left) for battery acid damage. There will be an on-board battery the size of a AA, unless it's been removed. There will be corroded diodes, chip legs, etc. You may also have some issues at the CPU or PSU. You need to also check the voltages coming out of the PSU (power supply). You can contact member seinologist to see if he may be able to help you fix them. He is a Berzerk master, but seems to be getting out of the hobby so best to catch him soon.

The monitor is a GO7, and I have ordered a G07 Super Duper Deluxe Repair kit from Bob Roberts to hopefully take care of that. I contacted Seinologist after your other post to see if he can work on mine, but he's swamped right now. Another KLOVer has contacted me to sell an extra board set he has which I will do. Eventually I would like to fix my other set because I hear this game is a huge pain in the ass and it's always nice to have a spare working board set. Thank you for your advice on the ZPU and I will start that in the meantime while waiting for the monitor parts to arrive. Now hopefully we can get RAM controls to start working on the repro bat joystick.
 
Well, it's update time. The G07 has been completely rebuilt (Thanks again Jpopson) and I now have a picture. I was a little nervous because there was no picture or glow at first, but after adjusting the B+ to 120 V and TP4 on VSU-100 to 5.15 I now have a display of blue and red lines so that is a start. I have also removed the battery and need to clean it up a little bit. I don't see much acid damage at all, but I will take closer look next week. I'm going to test the ribbon cables and look for suitable replacements from the posts I have seen on here. It looks like I am headed in the right direction.
 
To test the ZPU board only:

Remove the three ribbon cables on the lower side and power on the machine.

You should get three beeps/flashes if the ZPU is working 100%.

If the LED stays on, try and look if the reset button is maybe stuck. (Try pull it up). It could also be defective from the battery leakage without it being visible on the outside. You can measure it though.

Not sure if I pointed you to it before, but this is a great explanation:
http://www.wowway.com/~ookpik72/brl.html


Here's a thread with some bits of info about getting the three Berzerk machines I found running again:
http://www.dragonslairfans.com/smfor/index.php?topic=1149.0
 
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