Robotron rug screen

JRANDSU

New member
Joined
Jan 29, 2010
Messages
21
Reaction score
0
Location
California
Hello everyone,
I just bought this today. The story is... The guy said he last played this game 6 months ago and it worked fine. Today we fire it up and it just shows the rug/carpet? screen. I searched the forums and tried some of the basics to get it to run. I tried plugging and unplugging connectors. Pushing the "resets". I started to take out the rom chips, but I started mangling them so I stopped. I did notice that one of the plugs for the or from the power supply was burned, and the PO jumped the wire to the back of the circuit board. It looks fine, except that it has a wire nut on it. So I was wondering where do I start? I am not very knowledgeable with electronics, but have done some. Plain and simple english would help me out a bunch if you have some ideas.
Oh yeah I am getting code 132, and all of the led's are lit.
Any Ideas?
Thanks
JR
 
Here are some photos...
 

Attachments

  • DSCN0420.jpg
    DSCN0420.jpg
    93.7 KB · Views: 32
  • DSCN0421.jpg
    DSCN0421.jpg
    95.6 KB · Views: 28
  • DSCN0422.jpg
    DSCN0422.jpg
    97.8 KB · Views: 26
The power supply needs a rebuild from the looks of it. The 132 error code indicates a defective RAM, which could also be a false read due to a defective power supply.

Test all of the voltages coming off of the power supply, and if they are all good replace the RAM in bank 3 position 2.
 
Thanks,
Where do you get power supplies rebuilt? What voltages am I looking for on the power supply and where?
And here is a dumb question, is the power supply the pc board on the side or the transformer thing on the base?
 
Last edited:
Thanks,
Where do you get power supplies rebuilt? What voltages am I looking for on the power supply and where?
And here is a dumb question, is the power supply the pc board on the side or the transformer thing on the base?

Dokert fixes them..

Both YellowDog and I fix them. It is the pc board with the 3 LED's on it and the big ass heat sink with the two transistors on it.

The connector that has the orange wire in pin number 1 is where you want to take your voltage readings.
pin 1 -5vdc
pin 2 key
pin 3 +12vdc
pin 4 -12vdc
pin 5 +12vdc
pin 6 +12vdc
pin 7 ground
pin 8 ground
pin 9 ground
pin 10 ground
pin 11 no connection
pin 12 +5vdc
pin 13 +5vdc
pin 14 +5vdc
pin 15 +5vdc
 
Ok everything is good except pins 5 and 6. They are both at 9.9v. What next?
 
Either BR1 or IC1 is bad, it is a toss up 50/50.

Pull the board out and flip it over, You are going to test bridge rectifier BR1. Set your meter for diode function and put the red lead on the minus lead for BR1, put the black lead on each of the AC leads and you should read .400-.600

Next put the black lead on the plus lead for BR1 and the red lead to each of the AC leads and you should again read .400-.600

BR1 looks like this

AC-------(+)
------------
------------
------------
(-)-------AC
 
Uh...
I think this is where I send it in.
I am done for tonight, Thanks.
 
Last edited:
Either BR1 or IC1 is bad, it is a toss up 50/50.

Pull the board out and flip it over, You are going to test bridge rectifier BR1. Set your meter for diode function and put the red lead on the minus lead for BR1, put the black lead on each of the AC leads and you should read .400-.600

Next put the black lead on the plus lead for BR1 and the red lead to each of the AC leads and you should again read .400-.600

BR1 looks like this

AC-------(+)
------------
------------
------------
(-)-------AC

It shouldn't be IC1, pins 5 & 6 are the unregulated +12VDC directly off of BR1. So either BR1 is bad or the big 18,000 uF cap is leaking and lowering the voltage. It sounds like a complete rebuild is in order. As long as the supply voltage coming off of the + pin of BR1 is > 5.5VDC the 2n6057 will be able to supply the +5VDC to the output. If he is getting 9V out the unregulated pins, it will be enough to supply the +5V regulated. And he said +5V was good.

ken
 
I am sure that you are right Ken, I didn't even bother pulling up the scat to look. It seemed pretty obvious to me that a rebuld was the correct answer.

I suspect that BR1 has a bad diode in it.
 
Pin #1 was 5.08v
Pin #3 was 11.88
Pin #4 was -12.5

I don't know if this sheds any more light on it.
 
Robotron is working great. Thanks to Yellowdog for repairs and replacing Rom chip? Thanks to Dokert for the power supply. My kids think the game is great!
 
Glad to hear it. That makes my day when I hear about a classic coming back from the dead.

Enjoy!

ken
 
Back
Top Bottom