(Topic ID: 197625)

[email protected] No 4 Corners Scoring!


4 years ago

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  • 14 posts
  • 2 Pinsiders participating
  • Latest reply 4 years ago by JKnPA
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#1 4 years ago

I just noticed my 4 Corners does not score. The relay is energized and the Lamp is Lit.
The 4 Corners only scores in Green, that is the normal operation on this Bingo.
Not all of the Green scoring is correct. I am taking data on what scores and doesn't.
Not sure that will tell me anything.
The Search unit does not stop to register a Score. I cleaned the contacts on the 'Corners relay'.
How do I isolate this problem?
* Thanks,

#2 4 years ago

Ok.......... this is the data I collected just for the GREEN scoring!
All 3 in a Line, and 4 in a Line ..... score correctly!
5 in a line ......... 9-10 ( right diagonal numbers) ; the scoring counter runs away into the upper stops!
5 in a Line......... 2-14 ( center numbers) ; same as above.
5 in a Line......... 15-12 ( left diagonal numbers) ; no scoring!
4 Corners setup............ relay energized and lite ON ( 4Corners scores Green 5 in a Line).
* I get a signal at #14-2 , input to Green score Disc at location B-18 and an output signal at #45, the input
to C.U. cam 13A,; but the cam doesn't stop long enough to register a Score.

Added over 5 years ago: ** Cam #13........ should have said ' cam does not turn".
Search unit...... does not stop to record a score.

#3 4 years ago

JK - check your replay counter units - especially the green. If the game can't clearly sense which position it's starting from, it can't count appropriately. Ensure none of the feeder wires are off of the solder points on the spider, and ensure all the feet from the spider are making good contact with the bakelite plate.

Clean the plate and ensure no carbon or dirt traces are left where the wipers move across. Lastly, with the spider off, ensure that the finger underneath (the common feeder) is undamaged (it's probably fine).

#4 4 years ago

The Search Index coil is not getting energized, so the search disc never stops to record a Score.
The Green does score in most cases, but not all as stated above.
I need 50V. on wire #80 on the Search unit to power on the Search coil at location 13A of the schematic.
How does that happen ? The Search Relay switches at the top do not get energized until the Search coil is
energized thru 'search index switch 17A at location 33K.

#5 4 years ago

The drag arms, as they sweep, transmit the 50V through the pressure wipers (the little arms that sit in the grooves to the right of the search disc). These energize the search relays. When 3 or more are closed the search index will power.

That's the basic theory. Check the silver arms that ride in the channels to ensure there is one in each slot.

If green is the only color in which this happens, I still think that it could be your replay counter for green - because if the replay counter is in an unknown state, the search index will not power or remain powered too long - basically, the behavior you are experiencing.

If on the other hand, the search relays are not firing, then your search disc is dirty, wiper arm damage exists or there is an arm off on the little grooves.

#6 4 years ago

Oh, one other important point - if the green scores disc is not working properly, then you'll have issues too.

#7 4 years ago

I cleaned the rivet contacts on the Search Disc, and the 'wiper arms' appear to be Ok.
Doesn't everything go thru Relay #3 to get a Score ? But relay#3 doesn't close until the Search index coil is
energized....... Yes or No ?
Also the Replay Cams index coil is not energized until the Search index switch 17B closes, so the Green Replay
Counter would not be an issue then...... Yes or No ?
What am I missing here...... I don't see it!

#8 4 years ago
Quoted from JKnPA:

But relay#3 doesn't close until the Search index coil is
energized....... Yes or No ?

No, - the relay #3 closes which powers the search index.

Quoted from JKnPA:

What am I missing here...... I don't see it!

Basically, the game has to check to see if you've already scored, assuming that it sees a winner. If you've cleaned the search disc and the arms (words fail me - there's a better name for those) - then you've got something wrong with the initial check.

The game still should have voltage on the appropriate rivets (you can check this in your manual and test them if you wish to see when balls are in the right holes), but if the score disc has, for example, a NO switch that isn't closing all the way or vice-versa on first step, then you will not score in that color.

Alternatively, if the game has a broken feeder wire to the spider units on the green score disc or the green replay counter disc, you will not earn replays correctly.

If there's dirt on either of those discs, then you may not earn replays correctly. Similarly if there's continuity problems.

I guess the question is - is it only in green? Reading back through, I realize I made an assumption. Does it ever score properly? Does it always score properly in other colors? That's where I was helping to troubleshoot.

If you're getting intermittent or improper scoring in all colors, you've already troubleshot 2/3 of the circuit. Your search relays (esp. #3) need to be reviewed - check for broken resistors and inspect gap of switches. Your search index relay has a small stack of switches that require VERY fine adjustment to work properly. -If- nothing is scoring properly, please observe the search index for minute pulses as the search disc turns. If it never happens at all, then your problem is likely in the search relays. If it does happen, then your problem is in the cleaning or adjustment of that switch stack.

Hope that's not too much info. Trying to start small and get bigger.

#9 4 years ago

Thank you for the detailed Post.
No, - the relay #3 closes which powers the search index.
When I am T/S the problem, I can't tell if the relays close first , or the Search Index coil energizes first.
How does Relay #3 close before the Search Index coil is energized?
Doesn't Search Relay switch 17A (N.O.) have to close to energize Relay #3 ?
What is this *3 safety relay switch in that circuit ? Is that how it is initially energized ?

#10 4 years ago

I'll have to delve back into the schematics to answer that question (my memory doesn't work so well sometimes), although it may be worth noting that in physical reality, those two events may happen simultaneously (when things are working).

The relay should power the search index and not the other way around. Check your manual for the search relay #3 and I think you'll find the safety switch - it probably shuts off circuitry leading elsewhere when the relay stays engaged. I'll dig into the schematics when I have a spare moment and let you know.

I should also say that relay #3 is required to power the search index, but there must be two additional relays closed as well. Again, memory, that fickle beast, may be getting the best of me. (again). But that is how I remember it working, anyway.

#11 4 years ago

I wouldn't expect anyone to remember any Bingo circuitry to memory. I have trouble remembering where I
put my glasses 15 min. ago........
Ok....... I found that *3 Safety relay. It is mounted on the center of the back door. My ID tag was torn in half,
so I really never noticed what it was. It's a N.C. switch in a parallel circuit with the #3 Search Relay.
I assume it powers the #3 Search relay when power is applied to wiper A on the Search Disc, thus
energizing the relay before the Search Disc stops for a Hit.
Also....... YELLOW scoring does NOT happen with 5 in a Line........ just noticed that, because I was only looking at
the GREEN data has stated above in Post #2.
RED scoring....... I think that works for 3,4,5 in a Line.
Now...........I'm thinking my problems are WORN RIVETS on the search Disc. Too many issues here to be limited
to one problem ! Just guessing though!

#12 4 years ago

correct, the most important thing to remember - if it scores properly in just ONE color, then you're probably chasing your tail with common areas. Examine your score and replay counter discs. Worn rivets on the search disc can happen, of course, just less likely than dirt or other trouble on those other areas.

#13 4 years ago

Ok............ Thank you.
I will keep you informed.
Tomorrow is another day...........

#14 4 years ago

Ok........ I fixed the problem. I was doing some relay testing that took me several days to take data.
1. I didn't realize at first that the #12 number did not score in any other configuration like Yellow or Green.
If I did, I may have found the solution sooner!
2. When testing the search relays...... Yellow scores were not energizing the relays for 5 in a Line.
That was my main focus of T/S.
*** Why my Fix to the 4 Corners fixed that problem........I don't know!
Solution......... I decided to work on the #12 Scoring issue first; I thought that would be the easier task!
I checked continuity from the Search Unit disc ( rivet for #12) to the Magic squares Unit.
I could not find continuity. When trying to look at the wires on the #12 lite socket, I found a
broken wire to the terminal adjacent to the slip ring assy. by the lite socket. Its part of the
"E" magic square Unit that contains 12,14,3,8.
That wire goes under the assy. to one of the slip rings.......me thinks.
Therefore no connection to the #12 circuit. The lite would lite, but never score!
* I resoldered the wire on.......... 4 Corners Works, and so does the Yellow scoring that failed earlier!

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