Motorola xm701-10 monitor

dyno

Well-known member
Joined
Apr 11, 2009
Messages
1,644
Reaction score
81
Location
Lower Mainland, Britsh Columbia
My game is working but all I am getting on the screen is raster lines and no graphics, I have never worked on one of these monitors before.Any idea where to start?
 
Start with a cap kit if you haven't done one. That's a 30 year old monitor and the caps should be replaced. The kit is only about $5 from Bob Roberts and it's a simple monitor to do a cap kit on since the pcb just pops right off the monitor frame.
 
The game is Avalanche by Atari and I know the game is working because you can coin it up and hear the game playing in the background. I will try a cap kit and see what happens.
 
Just looked at the monitor chassis and notice that the 5v regulator is missing so I am hoping that is the problem. In the parts list for the monitor it says that it is an A8U what would be a replacement part I could use?

Did a cross reference with NTE and it said a replacement would be a NTE130 which I think is that same as a 2n3055 whichc I have a few new ones, my borther gave me a bunch of parts from when he took electronics in school and there are two 2n3055 in the parts he gave me.:)
 
Last edited:
Put on a new 5v regulator but no luck, still nothing on screen but raster lines. Should the 5v regulator be generating some heat since it has a heatsink attached to it, I am not getting any heat of the one I installed.
 
I don't have the schematics in front of me, but as I recall, the xm501/701 have a 5volt power supply for external use. In other words, it's not used on the monitor, it's for use powering a game pcb or something similar. There is actually a 5v output in the connector, but most games do not use it.

My money is still on a capkit. That should be your very FIRST thing to do before wasting anymore time.
 
Somewhere around here is a thread with pics I made about a 23" B&W monitor that had just raster lines only when connected to a known working Space Invaders. After the cap kit it worked fine...
 
I'll try to track that thread down, thanks. Here are some pics I took of the chassis and the picture when powered up. It looks like 3 caps have been replaced because they look newer than everything else on the chassis. I can hear the game in the background so I am assume it is a monitor issue.
 

Attachments

  • avalanchemonitor 001.jpg
    avalanchemonitor 001.jpg
    93 KB · Views: 41
  • avalanchemonitor 002.jpg
    avalanchemonitor 002.jpg
    96.4 KB · Views: 32
I just had a similar problem with my XM700 and I replaced transistors Q1, Q2, Q3 and Q4, as well a capkit and this was the result - Barry
 

Attachments

  • IMG_1141.jpg
    IMG_1141.jpg
    22.9 KB · Views: 35
I got them from mouser.

Q1 is - NTE123ap - http://www.mouser.com/ProductDetail/NTE/NTE123AP/?qs=sGAEpiMZZMsagl7BRmp5TQ24yCmicdJkk9dtnKebcpw=

Q2 is NTE159 - http://www.mouser.com/ProductDetail/NTE/NTE159/?qs=sGAEpiMZZMsagl7BRmp5TQ24yCmicdJkBtw7QptEVMM=

Q3 is NTE154 - http://www.mouser.com/ProductDetail/NTE/NTE154/?qs=sGAEpiMZZMsagl7BRmp5TQ24yCmicdJkHYbUmSvxG00=

Q4 is NTE123AP - http://www.mouser.com/ProductDetail/NTE/NTE123AP/?qs=sGAEpiMZZMsagl7BRmp5TQ24yCmicdJkk9dtnKebcpw=

These are the cross referenced motorola to NTE numbers. - Barry

I also replaced most of the caps on the board. I got the XM701 cap kit from bob roberts and since I have an XM700 some of the caps aren't the same so I had to get them from mouser as well.
 
Last edited:
It's Alive! I replaced the three 50uf 50v caps and the 470uf 16v cap and the game works! Thanks for all your help. Now I know this is the monitor section but since we are here sometmes when I turn the game on there is a loud noise coming from the speaker and there is garbage on the screen, but if I turn it off and back on the game works fine or if I connect and disconnect the board from the edge connector the game works okay. When I do the self test for the game is shows that the RAM and ROM are okay but below that it has shown number 77,89, 7C and 7B and I have no idea what that means. Does that sound like a board problem or a bad connection somewhere?
 

Attachments

  • avalanchemonitor 005.jpg
    avalanchemonitor 005.jpg
    90.8 KB · Views: 22
  • avalanchemonitor 007.jpg
    avalanchemonitor 007.jpg
    90.5 KB · Views: 25
Looks like it figured out what the numbers under the RAM and ROM during self test, the numbers are the positon on the paddle when you turn it. Also figured out what was going on with the loud noise and garbage on th screen, it seems after you turn the game off you have to leave it off between 5- 10 seconds before you turn it back on. I guess I was turning it on to quickly after turning it off so am thinking maybe the board needs time to discharge, just a guess. Anyways all seems well now.
 
It's Alive! I replaced the three 50uf 50v caps and the 470uf 16v cap and the game works! Thanks for all your help. Now I know this is the monitor section but since we are here sometmes when I turn the game on there is a loud noise coming from the speaker and there is garbage on the screen, but if I turn it off and back on the game works fine or if I connect and disconnect the board from the edge connector the game works okay. When I do the self test for the game is shows that the RAM and ROM are okay but below that it has shown number 77,89, 7C and 7B and I have no idea what that means. Does that sound like a board problem or a bad connection somewhere?

Sweet. I'm glad it was just caps. I don't know for sure what fixed mine but I wanted to replace known suspect components at one shot. - Barry
 
I jumped the gun on the board making noise and garbage on the screen, I am still having the problem even if the game is turned of for along time. Not sure if it's the board or a bad connection somewhere. It passes its self-test so could it still be the board? When I first got the board the voltage coming in was low so I put a new voltage regulator in it, which caused the voltage to be 7v+ Iam wondering if it damaged soemthing on the board.
 
Back
Top Bottom