(Topic ID: 126620)

What're these and are they the reason for no lights?

By embryonjohn

8 years ago


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  • 11 posts
  • 6 Pinsiders participating
  • Latest reply 8 years ago by EMsInKC
  • Topic is favorited by 2 Pinsiders

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#1 8 years ago

I have a perfectly playing Kings & Queens except for one issue: the 4 lights under/illuminating the cascading kickout saucers won't come on after the all the rollovers are flipped. They're the pink ketchup packet jobbers in the photo. They lead right into the light sockets so I thought they may be the culprit. I have LEDs only under the inserts ~ could that be the reason they're not triggering the lights to turn on?

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#2 8 years ago

Those are 75ohm 'sand' resistors, and are there to allow #44 bulbs to be used on the 24V part of the circuit (instead of the usual 6V circuit for all the other lights). Only #44 bulbs can be used on those sockets that have the resistors wired into them (not #47s, not LEDs, etc.; only #44s). (At least not without changing out the resistors to redo the circuit to match an alternate bulb.)

But those resistors do sometimes fail. If you unsolder one end, then they can be checked with a meter.

You can get ceramic resistor equivalents to replace them if need be.

#3 8 years ago

Yea, put 44's back in!

#4 8 years ago
Quoted from DirtFlipper:

Those are 75ohm 'sand' resistors, and are there to allow #44 bulbs to be used on the 24V part of the circuit (instead of the usual 6V circuit for all the other lights). Only #44 bulbs can be used on those sockets that have the resistors wired into them (not #47s, not LEDs, etc.; only #44s). (At least not without changing out the resistors to redo the circuit to match an alternate bulb.)
But those resistors do sometimes fail. If you unsolder one end, then they can be checked with a meter.
You can get ceramic resistor equivalents to replace them if need be.

Dirt, correct me if I'm wrong here, but Gottlieb used those resistors in many games to run lamps off the 24v circuit. In particular, they used them to run the "Last Ball In Play" lamps in many 60s games. In those games, 455s pretty much have to be used because 44s will burn brighter than normal (the voltage isn't being knocked down quite enough) and will not have very long life, so you use the blinkers to solve the issue.

I can understand the LEDs, but I guess you're saying that because a 47 draws less amps than a 44 (they've both 6.3v lamps) that they won't illuminate? So why would a 47 not work, given that 44s used in a circuit with the sand resistors generally don't last as long because they burn brighter and hotter and burn out faster?

#5 8 years ago

35 ohm was used in series with flashers (Central Park last ball in play), 75 ohm was used in series with 44 bulbs. 150 ohms for 47s...

Its all about the resistance and voltage drop. And deriving 6 volt drop across the bulb to get it lit.

6volts across the bulb means 19 volts across the 75 ohm resister. Suggesting current of .25 amps. A 44 bulb "hot" is 24 ohms.

There you go, 4 years of EE in college not wasted.

Ken

#6 8 years ago

Furthering the math...a 47 is ~50 ohms (hot) thus getting 6v out of the 25.

Now if you put a 50 ohm 47 in series with a 75 ohm resistor, its going to get about 10 volts etc, they dont last long, burn out in a minute or two...

Put 44s back in or change your resistors to match the bulb/led you use. Ive got about 200 44s sitting in my stash if you need some.

#7 8 years ago

For the "Last Ball in Play" sockets, those have a 35ohm resistor instead of the 75ohm, and a 455 flasher bulb has to be used.

#44s are .25 amp and #47s are .15 amp. 47s will certainly light for awhile (and brightly!), but will burn out after a short time. The #44s are fine there (since that's what the sand resistor was sized for). It's not been my observation that the #44s are brighter/hotter/shorter life in that application. #47s most definitely will in those sockets.

A quick math check would be 25V-6.3V = 18.7V; 18.7V/0.25A = 74.8ohms (so there's the 75 ohms). (I used 25V instead of 24V, after checking a 1960's schematic; it's 25V on the schematic.)

If one wanted to use #47s instead, then would need 18.7V/0.15A = 124.7ohms, or call it 125ohm resistor. Could do that by replacing all those resistors.

Otherwise you're running 25V-(0.15A)*(75ohms) = 25V-11.25V = 13.75V through a 6.3V bulb using #47s. Yes, they're very bright (and short-lived).

455s are 6.5V and 0.5A, so 25V-6.5V = 18.5V/0.5A = 37ohms. They use 35ohm resistors on those (there's probably another couple ohms in series with it via a relay in the circuit).

The net is, use #44s with the 75ohm resistors, and #455 flashers with the 35ohm resistors. Or plan on changing resistors to match the load.

#8 8 years ago

Wow after reading your post DF I feel like the Coyote!!

#9 8 years ago

Guess who no has lights for his o-so-important pinball & coffee this morning? Me, thanks to you. You guys do amazing things on here. Thank you.

#10 8 years ago
Quoted from DirtFlipper:

For the "Last Ball in Play" sockets, those have a 35ohm resistor instead of the 75ohm, and a 455 flasher bulb has to be used.
#44s are .25 amp and #47s are .15 amp. 47s will certainly light for awhile (and brightly!), but will burn out after a short time. The #44s are fine there (since that's what the sand resistor was sized for). It's not been my observation that the #44s are brighter/hotter/shorter life in that application. #47s most definitely will in those sockets.
A quick math check would be 25V-6.3V = 18.7V; 18.7V/0.25A = 74.8ohms (so there's the 75 ohms). (I used 25V instead of 24V, after checking a 1960's schematic; it's 25V on the schematic.)
If one wanted to use #47s instead, then would need 18.7V/0.15A = 124.7ohms, or call it 125ohm resistor. Could do that by replacing all those resistors.
Otherwise you're running 25V-(0.15A)*(75ohms) = 25V-11.25V = 13.75V through a 6.3V bulb using #47s. Yes, they're very bright (and short-lived).
455s are 6.5V and 0.5A, so 25V-6.5V = 18.5V/0.5A = 37ohms. They use 35ohm resistors on those (there's probably another couple ohms in series with it via a relay in the circuit).
The net is, use #44s with the 75ohm resistors, and #455 flashers with the 35ohm resistors. Or plan on changing resistors to match the load.

Dirt & Pinhead - Great info that will come in handy.

#11 8 years ago

Thanks for all the education guys, much appreciated!!!

I knew that 44s are .25 and 47s are .15, but showing the math on how they get to the resistor rating was extremely helpful.

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