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Time machine chime unit

lukewells

lukewells

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Does anyone have a Data East Time Machine (or is familiar with the chime unit in them?

Basically my chime unit does nothing at all.

I have power on the power lugs of the coils, and I can ground the other side of the coil and get a nice spark, but the coil does not fire.

The diodes are installed the right way round and are not shorted

All 3 coils are aprox 14ohm

THe plungers move freely by hand


The plungers are a hollow metal tube with a plastic tip, which I thought was odd, but it could just be to reduce the mass so it is not too loud? Or has something sabotaged it so that it doesn't chime?

Any ideas? I've never seen a coil that won't fire before when it has a valid power source and a valid ground path. It's got to be the plunger?
 
lukewells said:
Does anyone have a Data East Time Machine (or is familiar with the chime unit in them?

Basically my chime unit does nothing at all.

I have power on the power lugs of the coils, and I can ground the other side of the coil and get a nice spark, but the coil does not fire.

Any ideas? I've never seen a coil that won't fire before when it has a valid power source and a valid ground path. It's got to be the plunger?
Click to expand...

I once saw an problem like that, with the jet bumpers on an Earthshaker. There seemed to be power present at the front end of each coil, but grounding the tail ends did nothing. That one turned out to be a open-circuit power link (zero-Ohm resistor) on the 'Aux Power' pcb. As you say, each coil should energise if it's o.k, has a good power source and a ground path.
 
pinballmania said:
Have you checked adjustment 47?
Click to expand...

Hi Andy,

I have not, but assumed that setting was for in-game and would not stop the coils from firing in coil test, or when I manually ground the coil?

I'll check later in case I have missed something stupid and it actually disables the coil power somehow, but fairly sure it's not wired anything clever like that
 
Jay Walker said:
I once saw an problem like that, with the jet bumpers on an Earthshaker. There seemed to be power present at the front end of each coil, but grounding the tail ends did nothing. That one turned out to be a open-circuit power link (zero-Ohm resistor) on the 'Aux Power' pcb. As you say, each coil should energise if it's o.k, has a good power source and a ground path.
Click to expand...

I'm getting a nice spark when grounding the coil, so was assuming an appropriate amount of current was passing through

HOWEVER, you've just got me thinking .....

On Data East Popcorn Popper Boards, there are a bunch of power resistors that coils on the A/B solenoid circuits sometimes use. I'd better check that out incase a previous owner has messed with it, potentially limiting the current too much for the coil to fire. (As the chime coils are going to be low current, it is possible that series resistors will be in play in this case)



I was once diagnosing a system 11A board where the feature lights were not working at all. I was probing through the circuit and everything looked like it was working, there was good power and also valid activity on the row and column drives, but no light output.

I noticed some fresh looking solder marks around the power resistors in the lamp circuit, but assumed the owner had just tried re-flowing some cracked solder joints. After not being able to find anything wrong, I took a closer look at the power resistors and all had become clear! The resistors were too high a value and thus were limiting the current sufficiently to stop the lamp strings from being able to light at all.

When I spoke to the owner, the original resistors apparently looked burnt, so he decided to change them for new ones that he had got from Maplin, not knowing that they had to be a specific value :rofl: So he sent it to me for repair when the entire light circuit stopped working, but was too embarrassed to tell me that he broke it changing the resistors :rolleyes:
 
Adjustment 47 is on "SUPER" which is the default after initialisation.

In coil test you hear that faint hum noise that you do when you test a magnet in a game with magnets.

My conclusion thus far is that there is something wrong with the plungers.

Does anyone have a Time machine and can photo their chime plungers?
 
JWG9999 kindly provided pictures of his chime unit, and my plungers match.

The last thing to try is to isolate a coil and try to fire it directly from a bench PSU
 
lukewells said:
JWG9999 kindly provided pictures of his chime unit, and my plungers match.

The last thing to try is to isolate a coil and try to fire it directly from a bench PSU
Click to expand...

The hum you describe in test mode says to me that the coils are trying to fire but the plungers aren't responding for whatever reason, liekwise when you short the lug.

Have you check the voltages on the lugs and are they in keeping with the other coils in the game?
 
Moonraker said:
The hum you describe in test mode says to me that the coils are trying to fire but the plungers aren't responding for whatever reason, liekwise when you short the lug.

Have you check the voltages on the lugs and are they in keeping with the other coils in the game?
Click to expand...

There are not many things that get me completely stuck, but this is one of them.

From an electronic point of view, I cannot see any reason why they do not work.

I have valid power on the power lug and I can apply a direct ground to the other lug (which generates a spark, indicating at least a reasonably high current passed through)

The coil resistances are valid so no shorts (all 3 I think were exactly 14ohm, which sounds reasonable for a lower power device)

The directions of the coils and plungers are consistent with those of JWG9999's machine

The power must be valid as the "klacker" coil is directly next to the chime unit and is connected in parallel directly to the same power source, and that fires absolutely fine.

Thus at this point in time, I can only think to be suspicious of the mechanical parts themselves (such as the plungers - even though they look identical to JWG9999's)
 
I would try raising the plungers off the down position slightly. Experiment with a small piece of wood or similar. I've found that some plungers don't have enough length in the coil to get moving. As little as 1/16th" or so lift into the coil helped to overcome the issue.
 
lukewells said:
There are not many things that get me completely stuck, but this is one of them.

From an electronic point of view, I cannot see any reason why they do not work.

I have valid power on the power lug and I can apply a direct ground to the other lug (which generates a spark, indicating at least a reasonably high current passed through)

The coil resistances are valid so no shorts (all 3 I think were exactly 14ohm, which sounds reasonable for a lower power device)

The directions of the coils and plungers are consistent with those of JWG9999's machine

The power must be valid as the "klacker" coil is directly next to the chime unit and is connected in parallel directly to the same power source, and that fires absolutely fine.

Thus at this point in time, I can only think to be suspicious of the mechanical parts themselves (such as the plungers - even though they look identical to JWG9999's)
Click to expand...


Have coil reference charts,that quote what resistance each coil should be,may not help here,but always good for reference
lmk if ya want a copy

poi
 
Weird question but here goes

with adj 47 to off,you do hear the chime sounds done thru the speakers?ie thru sound board,in case that adj aint working?
 
pinballmania said:
I would try raising the plungers off the down position slightly. Experiment with a small piece of wood or similar. I've found that some plungers don't have enough length in the coil to get moving. As little as 1/16th" or so lift into the coil helped to overcome the issue.
Click to expand...

JACKPOT - ching-ching-ching-chinga-ling-ching-ching klack klack klack JACKPOT - ching-ching-ching-chinga-ling-ching-ching klack klack klack


Thanks Andy:thumbs:, there is me investigating non-existent electrical issues, and you had the simple answer there!

Now I feel like a moron! :rofl:
 
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