Jack In The Box
Gottlieb, 1973
Jumping Jack
Gottlieb, 1973You're currently viewing posts by Pinsider davidr415.
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Fairly frequently the ball gets hung up rapidly bouncing from the pop bumper to either the nearby side or lower rubber. Rapidly back and forth like a machine gun. I have to tilt out of it to stop it. I’ve tried playfield angles from 3 1/2 to 6 1/2 deg and it still happens? New rubbers. Pop bumpers have been converted to DC operated solenoids.
I haven't tried oversized rubber rings yet, but I did reduce the problem by "de-tuning" the solenoid (at least that is what I think I did). i adjusted the the EOS switch where the leaves separate earlier in the stroke. So far it seems to be helping. Time will tell if it is completely solved. I have noted that the AC coils are still in the pin despite it being conveted to DC. I have some DC, higher resistance coils i can try as a last resort.
Quoted from edednedy:Wouldn't it be easier to reduce the power by removing the rectifiers and converting back to AC?
Perhaps… I may come around to this solution eventually. The person that did the DC conversion used a single rectifier to drive all 4 flippers and the 2 pop bumpers. I’ll have to figure out the circuit now and as it used to be. I like the dc flippers and plan to leave them like that… so.. it may be a better solution to return to AC, but not necessarily easier ( for me).
Quoted from BorgDog:curious as to what DC voltage you are seeing on the flippers and pops?
I also at most see a couple seconds of pop to wall bouncing back and forth, but I am stock. Gameplay also changed a lot for the better when I lowered it down in slope. everyone seems to want to crank everything up to make it harder, but I'm still not down to the 3.5 degrees the manual says to put it at, probably 4.5-5. I might have to try the 3.5 (leg levelers all the way in) sometime, but may actually make it too easy to shoot back to the top holes.
30 v dc off of rectifier ( not high tapped). I’ve tried angles from 3.5 to current 6. I get the machine gunning at all angles. Steeper seems better.
Quoted from BorgDog:yeah, 30VDC is kinda high, when gottlieb went DC in system1 it was only 25VDC and they used coils with higher ohms as well. I think they did some later em's with DC flippers and maybe pops but don't know the specs on those.
I'd probably put it back to AC and high tap if you wanted a little boost.
I’d try that if I could figure out how. All the dc wiring was done in one color of wire and efficiently bundled so not obvious where wires go or come from. I’ll dig deeper!
Quoted from BubbaK:I'd love to see how its wired. I wanted to do the same thing to a few games using 1 rectifier. I have an EM Cleopatra with the DC pops and flippers and its a lot more reactive. For the flippers, they use A-17875 and the pops are A-1496. May try those coils?
Edit*** Not sure if they will fit, on the back of the manual it lists new items appearing in this game and has new coil mounting bracket and stops for the flipper and pop bumper coils. I think the coil stops are different for DC coils?
When I get a few minutes, I'll map out the wiring and share it.
I have some Williams AE-23-800-03 which seem equivalent to the A-5194 (recommended for DC conversion according to one article I read) so I may stick one in just to see what happens.
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Quoted from BubbaK:I'd love to see how its wired. I wanted to do the same thing to a few games using 1 rectifier. I have an EM Cleopatra with the DC pops and flippers and its a lot more reactive. For the flippers, they use A-17875 and the pops are A-1496. May try those coils?
Edit*** Not sure if they will fit, on the back of the manual it lists new items appearing in this game and has new coil mounting bracket and stops for the flipper and pop bumper coils. I think the coil stops are different for DC coils?
Here is the circuit that is used..
I tried several things... tried converting back to AC.. too slow. I didn't like the way it played. I tried de-tuning the pops by moving the EOS switch closer to the playfield, thus reducing the duration of the DC pulse to the pop solenoid. This helped reduce the strength of the pops, but I still got machinegunning occasionally. Ultimately, I installed slightly bigger rubbers adjacent to the pops and this seems to have done the trick.
I didn't have any higher resistance coils to try.. this may have worked.
dc circuit (resized).jpgQuoted from fixintoplay:Just noticed this posting and read the responses. I was plagued with the same issue a few years ago with my son's Hollywood: ball machine-gunning between one pop bumper and its opposing rebound rubber. The solution for me was simple. I moved the top playfield post holding that rubber ring a fraction of an inch outward -- just enough to change its radial geometry and bounce dynamics. It worked. Of course I had to drill another post hole, but it's barely noticeable. Maybe it was just machine, but I thought I'd mention this.
Seems like a good way to go. How far did you move it? A fraction of an inch could mean many things
Quoted from fixintoplay:I can't recall exactly, and I don't have access to the machine right now. Guessing 1/8" to try to keep the old and new holes covered beneath the post base. But before you drill a new hole, try these tricks first (I didn't think of them at the time):
a. experiment with the ring tension by using a larger diameter ring;
a. remove one fat plastic post and just use the thin metal post as a test. It will change the angle of the ring which should be enough to make a difference. If it works, cut/modify the plastic post into 2 pieces to keep the ring from moving up/down.
Larger rings is what fixed the problem for me. I like trying a metal post in place of one plastic pillar… lessons tension and changes angle. Great ideas!
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Kingsland, TX