feature lamp always on

[slither]

So I have this lamp that appears to be stuck on,at about 1/2 brightness. It is on the right rollover,near the flipper. The switch here activates the multi ball when lit. That part is working ok, it only activates after the target sequence to activate has been met. At that point the lamp gets quite a bit brighter, and returns to the say 1/2 brightness after switch is activated. I have checked under pf for possible shorts, etc, lamp socket is pretty isolated, nothing close by. Tested the driver transistor for the lamp, its ok..connector seems ok. Cannot see any shorts, bared wire in the wire leading from lamp to connector. Any ideas?...

 

[luch]

what game ?

 

[atariaction]

use jumpers to attach a new socket and lamp to the wires. if lamp is good that way then bad socket or solder connection.

 

[slither]

Its on a Spring Break, I have done a lot of work on this game, barely played, playfield was extremely dirty, plastics as well, new rubbers all around, good cleaning, waxing. had an alternate translite made, the original just killed this game. Added led s , moved flash lamps , very colorful. I actually love this game, it got a bad rap, everyone who plays it enjoys it. Great sounds, music (kind of ripped off the beach boys in spots ), ramp shots, multi ball etc. I am glad I took a chance on it.
Thanks Mike I will try that today !!

 

[sylvain]

In my experience, this issue is caused by a bad lamp darlington driver transistor on the Driver board (if there is only one lamp doing this). Even if it tested 'good'.
If multiple lamps stay partly dim, then it could be a poor ground issue between MPU-Driver.

Good luck!
-Sylvain.

 

[slither]

yes I tried jumpering and the other socket did the same. Its only the one bulb, I have another transistor and will replace today. Thanks Sylvain... This is the last of many light issues that haunted this machine, hardly any lights were on when I got it.

 

[atariaction]

When I first started reading your post my initial thought was the lamp transistor but then read that you tested it. I would especially suspect it now that the socket has been ruled out. Good luck!

 

[atariaction]

If you don't have one on hand you can check the schematics for one that is not used and use that one.

 

[slither]

yep, I got some when I purchased the pin, from digi key, one day delivery from the USA, only 8$ Canadian , by fed ex...how awesome is that !!! lol. Thanks !!

 

[slither]

When I first started reading your post my initial thought was the lamp transistor but then read that you tested it. I would especially suspect it now that the socket has been ruled out. Good luck!

yes, me too, but it tests fine, I believe the range is .4-.6..

 

[atariaction]

That is correct range. Does not hurt to try and rule out the transistor. Cheap enough