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Space Invaders Extra Ball Lamps Not Doing Much!

Solar Sailer

Solar Sailer

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so @asty and I have a conf call this morning to go through an issue with both extra ball lamps by the left and right drains on SI.
They dont work!
I've checked the continuity bsck to the connector on J2 and though separate circuits I get a tone on both connector pin 1 and 2 when I test the right lamp back to pin 1.

In test the dont flash. When I ground Q45 i get a slight flash on the right extra ball.
When I ground q31, nothing on the left extra ball.
both scrs have been replaced.

All other controlled and GI lamps are fine.

Any one had a similar experience on an early Bally?

Seems strange both the same feature lamps won't play!
 
Lamp Driver board issues or bad lamp holders.

Where did you get the SCRs from is first question?

Second question is have you tried manually grounding the lamp at the holder?

Third question have you got another lamp driver board to try?
 
I replaced the scr’s for @solar sailor. All came from GPE in the states. Board was tested in another machine before being sent back to Paul.
 
check your dip switches on the mpu are fully on or off and not stuck in between for any setting,then the old favourite switch test to check no stuck switches are causing weird issues
 
Ok, so here are my additional thoughts:

Using the schematic for the lamp driver you can determine a commonality here. Both lamp are related to the sixteen decoders number 15 output which is the last output in the line. Each output is associated with 4 lamps usually because there are 4 decoders being strobed in sequence.

So, checking the other lamps on output 15 here we get 1 that is Not Used and 1 that is the drop target special. So check the drop target special lamp in lamp test to see if it is working or not?

If the board has been repaired and tested in another game already (where decoder output 15 was being used) then that leaves the wiring/connector pins at lamp board J4 pins 14-17 and or a cpu related issue.
 
stevebm1 said:
check your dip switches on the mpu are fully on or off and not stuck in between for any setting,then the old favourite switch test to check no stuck switches are causing weird issues
Click to expand...

I lost the sound yesterday. Now its back.
Going to look at the board now. Its a MUPHA board. Not much on the Web about them.

I took a supply from another lamp to see if it would light but no and also the lamp I took it the supply from did not work either.

I feel I'm so close!
 
Put a meter on the cathode and gate legs of the SCR in question what voltage do you get?
 
stevebm1 said:
check your dip switches on the mpu are fully on or off and not stuck in between for any setting,then the old favourite switch test to check no stuck switches are causing weird issues
Click to expand...
I cant clear switch 36 - right slingshot for some reason.
 
Now you have cleared the errors. I would start by manually grounding the lamp at the holder If no change then put a meter on the cathode and gate legs of the SCR in question. Do you get 0.5v or thereabouts?
 
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Markjduk said:
Now you have cleared the errors. I would start by manually grounding the lamp at the holder and then put a meter on the cathode and gate legs of the SCR in question. Do you get 0.5v or thereabouts?
Click to expand...
Hi Mark

Thanks for this. That's my next job.

Regards
Paul
 
ok so @astyy came round and ate my last supply of Greggs sausage rolls in return for pinball favours with his MM.

I noted at the weekend I was getting continuity across pins 1 and 2 in J2 but not at the connector.
Closer inspection of the Pindorabox might be the route cause so dropped them a note to confirm.

If you focus in you can see bridges between pins 1 to 4.

The displays are back from Pinballs Displays with an apology.
The white displays are more power hungry and the IC's Gianfri put in struggled so replaced them.
 

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The chaps at Pindora have asked for J2 back for repair or replace.
Looks to be the root cause.
I'll update the shop log in due course.
Just Flippers to go now!
 
myPinballs said:
Ok, so here are my additional thoughts:

Using the schematic for the lamp driver you can determine a commonality here. Both lamp are related to the sixteen decoders number 15 output which is the last output in the line. Each output is associated with 4 lamps usually because there are 4 decoders being strobed in sequence.

So, checking the other lamps on output 15 here we get 1 that is Not Used and 1 that is the drop target special. So check the drop target special lamp in lamp test to see if it is working or not?

If the board has been repaired and tested in another game already (where decoder output 15 was being used) then that leaves the wiring/connector pins at lamp board J4 pins 14-17 and or a cpu related issue.
Click to expand...
Hi Jim

Drop target special when lit works a treat.
 

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Solar Sailer said:
Hi Jim

Drop target special when lit works a treat.
Click to expand...

This was a thought in response to other posts saying the driver board was tested working in another game, but it turns out scrs were blown on it and also the was no mention earlier of this pindora add-on thing. Always remove any add-on boards first when you get a weird fault!!
 
myPinballs said:
This was a thought in response to other posts saying the driver board was tested working in another game, but it turns out scrs were blown on it and also the was no mention earlier of this pindora add-on thing. Always remove any add-on boards first when you get a weird fault!!
Click to expand...

What I have learnt this week is to install item by item and test and not all at once!
 
When I replaced blown scr’s I new nothing of this pindora add on. When I sent it back (like I said in an earlier post) it had been tested in another machine and was fully working.
 
Yep. And I put the pindora on straight away thinking it had passed some sort of QC.

Lesson learnt!

But the pindora shorted your good work on q45.

I've put Comets in SI so need the anti flicker add on.
 
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