What's new
Pinball info

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Vector display problem

domlouis

Registered
Joined
May 28, 2014
Messages
1,666
Location
Derby
Hello
I have started to think that fixing pins is more rewarding that playing them. I must be getting mad.
So last week i fixed a flipper that kept on flipping frantically by replacing the coil (advice from this very forum). That was my first coil replacement and it went swimmingly ok. Probably helped by the fact that at last I have understood how I am meant to solder.
Anyway that's not the purpose of this thread, my next (and last at the moment) problem is the displays on my vector. None of them are on. I know they are ok because I had them tested and they were working fine. And also occasionally numbers appear on some of them. Otherwise all displays on the back box are blank. It looks like a central problem as opposed to a problem at each display. But the question is: where do I start? I don't even know which board in the back box drives the displays... Any help welcome. Keep it simple. Learner here.
Thank you
Dom
 
Could be something simple like turning the pot up on the sol driver board , us a electrical screw driver as there is over 100volts in that area and keep one hand in your pocket .
 
Try reseating connector J1 on the MPU and J3 on the Sol Driver board. The former contains the majority of the wires that daisy chain all the displays.
 
Check if there's an orange glow visible at the lower edge of the display envelopes, showing that the 185v power rail is present, or v. carefully measure for it at the test points of the displays

The high voltage, logic voltage and digit/segment wiring is mostly common to all the displays, except for each ports' own "Latch Enable", which locks the display segment data into the small chip of the display pcb, allowing each display to show a different number on each otherwise common digit at the same time.

In processor terms, the display pcb's are each loaded with the required number for the same digit, before that digit line is operated, lighting the digit in all five (or six, in this case) simultaneously. E.g. the "1's" digit would usually have '0' in the Player score displays, but the ball-in-play for the Status display, changing to a 0 when a Match number appears
 
Try reseating connector J1 on the MPU and J3 on the Sol Driver board. The former contains the majority of the wires that daisy chain all the displays.
I have tried reseating all the connectors already once. I will try again. I did notice that some could do with brushing a bit as they are quite dirty. Anyway that made no difference...

Check if there's an orange glow visible at the lower edge of the display envelopes, showing that the 185v power rail is present, or v. carefully measure for it at the test points of the displays

The high voltage, logic voltage and digit/segment wiring is mostly common to all the displays, except for each ports' own "Latch Enable", which locks the display segment data into the small chip of the display pcb, allowing each display to show a different number on each otherwise common digit at the same time.

In processor terms, the display pcb's are each loaded with the required number for the same digit, before that digit line is operated, lighting the digit in all five (or six, in this case) simultaneously. E.g. the "1's" digit would usually have '0' in the Player score displays, but the ball-in-play for the Status display, changing to a 0 when a Match number appears
I'll have a look but i don't remember seeing an orange glow visible. I think i would have spotted it. So that would show that the 185V power rail is NOT present? And i should go and try to find out why not?
 
On the power supply board TP2 what is the reading ? Think it's J4 pin 6 190v
Also on that board F2 fuse ok ?
On sol board what is Tp4 and TP2 reading ?
 
I'll have a look on Friday night and let you know Carl. Thanks for the tip.
Sorry I have not tried the screw driver option yet. It felt a bit outside of my comfort zone.
 
Yes, a faint glow at the lower edge of the glass envelope shows that the display high voltage is present. It may be masked by the plastic support frame from a normal viewing angle, but visible when looking down at the display from up close

I'd be cautious of altering the trimmer 'pot', VR1 of the solenoid driver board, without measuring the output voltage while doing so. Turning the hv up too far can damage the envelopes
 
On my original post Dom mention that numbers appear on the display sometimes, if the pot was turned to low ,this could give the symptoms what has been described !
Hence why I suggested to turn it up (set to low ) :)
 
Connectors still suspect for me, you mentioned they're tarnished but wires can be loose in the IDC slots or cold solder joints below too. I'd work through the TPs to work out where the necessary voltages are being lost.
 
Carl
Values measured tonight
Sol board
TP2 132VDC
TP4 230VDC
Power supply board
TP2 227VDC
Measured at pin 6 on J4 also 227VDC
Fuse F2 ok.
Makes any sense?
When I look at the schematic I can see TP2 on power supply board should be 230VDC. But pin 6 on J4 should be at 190VDC?
Is that part of the problem?
 

Attachments

  • 15489691589103399724419060111052.jpg
    15489691589103399724419060111052.jpg
    99.7 KB · Views: 11
Also I mentioned that the odd numbers appear. Here is an example.
 

Attachments

  • 20190131_211440.jpg
    20190131_211440.jpg
    73.9 KB · Views: 17
And I can see no Orange glow but I am not sure that I am looking In the right place because even on the one display that shows occasional number, I cannot see the glow. Where am I to look?
 
Tp2 is too low at 132v. Nominally it’s 190v but can be wound down to 160v or so and still work. But 132v is not enough. Try adjusting it up with the rotary potentiometer. If it won’t adjust then the high power section probably needs rebuilding.
 
I have just measured TP2 on all the display board and they are all at 132-134 VDC. So I think that ties in with what Andy but said.
 
Any special advice on adjustment of the potentiometer? I presume this is it BTW. That blue thing that says adjust.
 

Attachments

  • 15489704733465935158626124133969.jpg
    15489704733465935158626124133969.jpg
    50.8 KB · Views: 12
So in Andy's words: the high power section needs rebuilding. In that the section on the sol board or on the power supply board.
And then: who can do this kind of work?
 
Interestingly even with 140VDC I can see more display than before. I can now see my score so this little adjustment has made a massive difference. Still can't see credits but that doesn't matter.
 
I think I have answered my last question. It is the high power section on the sol driver board where 230v gets regulated to 190VDC. I have found the area of the schematic that deals with that.
How do I go about trying to determine which component (resistance etc) need replacing?
 
Cannot get to my manual at the mo so send Andy a email the legend will sort you out :thumbs:
Check his site , I think he does a kit ?
 
I got lucky ;)

Q22 ,Q23 and Q21 will completely rebuild that section , but Q21 is obsolete but there is a substitute transistor for it ! Everything is on Andy's site !!
 
bux84 is the one that replaces the obselete Q21,ive rebuilt quite a few of these,it's simple enough to do once you have all the components in place to perform the repair
 
You should also check the resistors once you’ve taken the transistors out and replace any that are incorrect. Also replace the big capacitor C26 160uF
 
If i understand it correctly, this is the area that needs rebuilding (see attached drawing extract).
Andy, I can't find a kit list for these parts on your website, probably because i am looking in the wrong place.
Regardless, could you put a complete kit list together, including the transistors, capacitors, resistors, potentiometer, etc? I don't know if i'll end up replacing them all but i might as well get all the relevant parts together just in case?
And then i'll place the order through the website.
Thanks.
Dom
 

Attachments

  • Sol board schematics.png
    Sol board schematics.png
    71.1 KB · Views: 15
Out of interest, does anyone know the voltage range that can be reached using the potentiometer? When I rotate it, I moved about a third of its available movement and the voltage only changed by 7-10 volts. Didn't feel right somehow.
 
Back
Top Bottom