Jrok in non working defender question...

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I have a defender everything comes on but I get a scrambled screen. Just installed my JROK multi williams board and harness.... any concerns around me turning it on and seeing if it works?

My main concern was if power supply was bad and it messed up my board (Is testing voltage from the jamma connector good enough that it will prevent damage if voltage is close?)

Thoughts?
 
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I have a defender everything comes on but I get a scrambled screen. Just installed my JROK multi williams board and harness.... any concerns around me turning it on and seeing if it works?

My main concern was if power supply was bad and it messed up my board (Is testing voltage from the jamma connector good enough that it will prevent damage if voltage is close?)

Thoughts?

With the JAMMA WMS board removed, power up the game and measure the 5v at the JAMMA connector. Just make sure it's right around 5v.

The +12v and -5v aren't use so they could be whacky or even missing.

- James
 
So.. Your old defender didn't work.. You bought a jamma harness and jamma jrok pcb.. I'm assuming you removed most if not all the original harness, installed the new one..

So why would you use the original power supply? Your game is now a modern jamma game.. Install a switching power supply, as the original won't plug into the jamma harness .. Or am I missing something?
 
So.. Your old defender didn't work.. You bought a jamma harness and jamma jrok pcb.. I'm assuming you removed most if not all the original harness, installed the new one..

So why would you use the original power supply? Your game is now a modern jamma game.. Install a switching power supply, as the original won't plug into the jamma harness .. Or am I missing something?

Jrok has a adapter harness that connects into the original harness.. You can run off the original power supply, and nothing is changed inside the cabinet.. It a non intrusive conversion.. I can put original boards back in my Jrok Defender in a matter of minutes, and ita all original again.. Nothing hacked cut or removed..
 
I didnt remove any of the harness... bought harness adapter from ken when he did the first run. Just connected the adapter and just played a game. Works great!

I could install a switching power supply and still might... wanted to test it out though have been too anxious.

So.. Your old defender didn't work.. You bought a jamma harness and jamma jrok pcb.. I'm assuming you removed most if not all the original harness, installed the new one..

So why would you use the original power supply? Your game is now a modern jamma game.. Install a switching power supply, as the original won't plug into the jamma harness .. Or am I missing something?
 
I didnt remove any of the harness... bought harness adapter from ken when he did the first run. Just connected the adapter and just played a game. Works great!

I could install a switching power supply and still might... wanted to test it out though have been too anxious.

Keep the original Power supply....
 
Ok will do... didn't know if there was a good reason to replace (such as reliability) Thanks!
 
Ok will do... didn't know if there was a good reason to replace (such as reliability) Thanks!

They are very reliable.. If you have issues PM Dokert he is the Jedi on these... From what I have read Williams games dont like switchers. The JroK board wiould work fine, but you have kept the rest of this cab original.. If you ever put a original board back in you will want the original working PS..
 
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Just had the game on for about 20 minutes... game went out got scrambled screen with JROK board. Was able to turn game off and get it to come back on. A few mins later went to a blue screen.

Am getting 5.7 volts to the board from the jamma chassis.

This a power supply issue?
 
Just had the game on for about 20 minutes... game went out got scrambled screen with JROK board. Was able to turn game off and get it to come back on. A few mins later went to a blue screen.

Am getting 5.7 volts to the board from the jamma chassis.

This a power supply issue?

Sounds like it. Worth rebuilding the power supply or just putting a 5v supply in just for the JAMMA harness. Last thing you want is the supply going out and a voltage spike killing the board.

- James
 
Thats what I was afraid of... I can turn it on and the board works but am now afraid to keep it on too long.

I am hoping if the board is still working it wasnt damged... will take care of power supply issue before playing again
 
Ahh.. Sorry, thought that you had to remove the original harness and couldn't use a defender ps.. My ignorance.. I'm just a super fan of Williams hardware that I've never looked into a multi Williams.. Just collected the uprights I liked to play.

My mistake. Good luck, Dokert is the man for rebuilds, so is yellowdog and Andre.. I'm actually shipping a box of dead Williams ps to Dokert soon as a thanks for helping out one of my customers.
 
From what I have read Williams games dont like switchers.

The biggest problem I had with a switcher in a williams cab was that it was out in the garage where the temp/climate changed frequently. i couldn't keep that voltage zero'd in at 5.1ish for nuthin so it would frequently suffer the carpet resets due to voltage drops. I got to wondering if the switcher couldn't manage that many boards at once, too. SOOOO dokert rebuilt the original PS and that thing became rock solid. He even put a adjustment pot on it.

Yellowdog's explanation of the other switcher issues is stored here- http://www.robotron2084guidebook.com/technical/carpetpatternresets/
 
Hey 1500, the biggest problem is that robo was in the garage and not in the house. Sheesh, what do you think living rooms and bedrooms are for anyway??
 
Remember, the jrok board doesn't need much power. I grabbed a 1 amp wall wart out of a junk box, and run my board with it.
 
Remember, the jrok board doesn't need much power. I grabbed a 1 amp wall wart out of a junk box, and run my board with it.

Yup, the 5v 500mA cell phone chargers are also a great source of power.
As long as it's regulated 5v DC and 500mA or better it should be good.

- James
 
Thats interesting... this may be a stupid question but would you just splice the cord and attach to board? Is there a negative wire that needs to go somewhere? Just curious thanks
 
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