Tech: Bally display problems

[Guest]

Archived from groups: rec.games.pinball (More info?)

Many thanks to those helping me to get my Vector working.

I have a display problem with the 6 digit vector scan display.
Originally, the 10 and 100 positions worked intermittently (not all
segments lit, strangely only problems with numbers 1,4,7).

I have reflowed the solder at the pins and the display, changed all the
100k resistors and even changed the level shifters at Q2, Q3 and the
digit drivers at Q8, Q9. No luck, the problems persist.

Since the changes, the 10,000 position now does not display full numbers
(it wasn't problematic previously).

I swapped the display with the credit display and everything worked, so
I think this problem is confined to the display board.

Any suggestions where I should look next?

Jim

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Yep, and only on 2 of the 6 digits. All the others light fine.

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

it could be the glass. i keep a spare around, and piggy back it
to the existing board for just a moment as a test. works great,
tells you whether it's the glass or not, and only takes about
30 seconds to do it.

Drone wrote:
> Many thanks to those helping me to get my Vector working.
>
> I have a display problem with the 6 digit vector scan display.
> Originally, the 10 and 100 positions worked intermittently (not all
> segments lit, strangely only problems with numbers 1,4,7).
>
> I have reflowed the solder at the pins and the display, changed all the
> 100k resistors and even changed the level shifters at Q2, Q3 and the
> digit drivers at Q8, Q9. No luck, the problems persist.
>
> Since the changes, the 10,000 position now does not display full numbers
> (it wasn't problematic previously).
>
> I swapped the display with the credit display and everything worked, so
> I think this problem is confined to the display board.
>
> Any suggestions where I should look next?
>
> Jim

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Not sure about the glass. I've seen all the digits display "8" either
during the test, or at some point. Could the glass still be suspect
here?

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

you mean if you put the game in display test, the display works
fine? then clean the MPU connector male header pins at the
upper left corner of the board with some fine sandpaper. if
this fixes the problem you will need to repin the connector
housing and replace the MPU board header pins.

Drone wrote:
> Not sure about the glass. I've seen all the digits display "8" either
> during the test, or at some point. Could the glass still be suspect
> here?

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Sorry for the confusion. I know that the all segments of the display
work (I don't see a "7" but I do see an "8"). I also know that if I
swap displays, the problem stays with this one. I have used the credit
display in the vector scan location and no problems. So I'm assuming
it's something on the board.

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

The ic chip can do weird stuff like that. When it's in test there are
no segments lit when seven comes around?.... But all light fine when
the 8's come up?

zTim