I am trying to work out why my Sure Shot bonus scoring is not working properly. Bonus is to be 1,000 points for each lit ball in the rack when the ball is drained. Sometimes the scoring is accurate, but more times than not the scoring is either one or two thousand points too much or too little.
Here are the current observations. When the ball enters the outhole, it activates the Q relay (bonus score control relay). This relay is held in for every 120 degree turn of the score motor (its connection is broken near the end of this cycle by the switch at 2B on the motor). I can confirm seeing the Q relay pulling in and staying pulled in for this cycle. In every 120 degree turn of the score motor, the bonus unit will traverse 5 of the 15 bonus unit contacts. So this means that the Q relay should be pulled in a total of 3 times for the bonus scoring. Upon completion of this, the reset bonus unit coil will activate, thus resetting the bonus unit position back to the beginning. What I see is this happening most of the time, but every now and then the bonus score unit will traverse only the first 2 lots of the 5 contact points (ie. get to about the 10th bonus unit contact point), and then will reset.
Another thing I noticed is the starting position of the bonus unit "spring contact" is not resting on the first bonus unit contact; it is positioned before the contact, resting against the bakelite. Is this correct, or should the spring contact be resting against the first bonus unit contact? The first image is of the bonus unit at its reset/starting position.
The second image shows the position of what I will call the "skate blade" of the spring contact relative to one of the fifteen bonus unit contacts. For this bonus unit, the blade is not centred over the contact, but comes to rest basically as seen in the image. Should the blade be roughly centred over the bonus unit contact? Is this easy to adjust?
The third image shows the final position of the spring contact relative to the bonus unit contacts. Here it is at the 15th bonus unit contact, and this is the position just before the reset bonus unit coil activates. Is this the correct position for the spring contact to finish at (ie. at the 15th bonus unit contact), or does it need to move past the 15th contact? Currently it goes no further.
The spring contact is moved through the 15 bonus unit contacts via the add bonus unit coil. The add bonus unit coil is activated by a combination of a switch on the Q relay and a switch at motor 1A. When the add bonus unit coil's plunger is pulled in, a normally open switch (the on add bonus unit switch) is closed. This in turn activates the Z relay (bonus score relay), which in turn activates the L relay (1,000 point relay), which then gives the 1,000 point scoring.
I noticed that if I manually push in the Z relay as fast as I can, back and forth, the 1,000 point scoring has no issues. For example, if I push in the Z relay 10 times over the course of a very short period of time (a few seconds), the scoring is accurate every time. So the Z relay's operation has no issue. Working back then, I noticed if I manually push in the add bonus unit coil's plunger rapidly, the scoring is not always accurate. I then had a closer look at the on add bonus unit switch. It is observed that the contacts in the switch blades are in physical contact with each other a good percentage while the add bonus unit coil's plunger is being pulled in. The fourth image shows the on add bonus unit switch (here with the switch open), and to the left of the switch, the lever arm that is connected to the add bonus unit coil's plunger. This is at the rest position. When the plunger is pulled in, the lever arm makes contact with the switch and closes the blades. I am thinking though that, because the blades are physically in contact for a large position of the cycle of the plunger, could there be the possibility that electrical contact is not continuous in the switch blades (while they are physically together)? This could lead to a double (or multiple) activation of the Z relay for a single plunge of the add bonus unit coil. Should the add bonus unit switch be adjusted such that it is closed near the end of the plunger pull in, this minimising the duration that the switch blades are together (and maybe then minimising the chances of a double or multiple Z relay activation)?
Sorry for the long-winded post, just trying to provide adequate information. Any assistance greatly appreciated.