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Wanted One of these things

Spandangler

Spandangler

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10 Years
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Jul 21, 2011
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Hey gang
I'm trying to reinstate the original switch wiring on my taxi jet bumpers.
Im assuming the capacitor failed and they didn't have a spare so the following bodge has ensued!

image.jpg


Notice the left bumper has the brown/green wire removed and a black wire soldered in its place. This is then soldered to the bottom lug of the pop bumper spoon switch. There is a separate black wire which is then soldered to the top lug of the spoon switch and goes to the cabinet earth braid!! :eek:

The result of this is, the pop switch fires the coil during game play but it won't fire in test mode.

I've managed to find the original wires hidden in the loom but I've noticed the actual switch is missing the small capacitor, so I'm reluctant to reinstate the wiring until it's there as I'm unsure of the consequence!

So does anyone have a couple of these I could buy? Pinballmania are out.

image.jpg


It's the small banded kind I'm after, not the blue one. I'll remove that as well when I get a new one.

I'm not sure of its value (not monitory) but hopefully one of you clever folks will.

Thanks in advance

Gaz
 
Errr, the stripey thing is a resistor isn't it? Not a capacitor?

The capacitor is the blue thing in the background.

Hard to tell the colours from that photo but it looks like the stripes from the top are brown, black, brown and then gold. You can decipher that using this chart to figure out what resistor you need:

cdn.instructables.com_FGG_TBC9_H4VQNQFG_FGGTBC9H4VQNQFG.LARGE.gif
 
Proves how much I know. Whatever it is I need one. Pretty sure that blue thing shouldn't be there either. It's not on the other switch
 
Thanks for that chart @Wiredworm I'll look closer tonight.

And Dave. I don't know. Whatever they stripey thing is in the picture, I need, as there is nothing at all on the other switch
 
Is that resistor soldered onto the end of the blue/brown cable that is meant to go onto the coil?

If you've got a multimeter then you can verify if it's ok or not just by setting your meter to resistance (ohms) and then placing a probe either side of it. Obviously you'll have to tweak the scale until you get a reading and then decode the rating based on the colour bandings.

Be useful to have some better pictures showing how it's all linked together.

I'm wondering why they'd do that - now I have to say that i'm also very new to all this - I wonder if the coil isn't the right rating for the job and the resistor is to counter-act that?

Anyone?
 
The pic is of the leaf switch which the pop bumper spoon is attached to.
The coil is makeshift as the other locked on and burnt out when the transistor blew, I have a replacement.
 
Is the resistor on the brown/black cable though?

Because a scan through the manual tells me that brown/black should actually go to the Top Ball Gate and it doesn't have anything to do with the pops?

2015-04-22_1507.png



Unless i'm going nuts?

@PudseyPinball?
 
Not sure I'm not at home. Anyway that switch is fine it's just an example of the part I need :)
 
Hi,

It looks like the bumper has indeed been bodged up, to operate as a simple solenoid, rather than being driven from the Cpu board. Not ideal, since the contacts aren't really up to it.

Taxi was one of the last Williams games to have what they called 'special' solenoids; the last 6 solenoids (#17 thru 22 on System 11) can each be operated more-or-less directly by some switching logic, rather than having the program work out that a bumper (or slingshot) switch has closed, and then respond.

Each of the bumper switches on Taxi is actually two seperate switches - the upper part, with the spoon blade, is the 'special' switch. The other part, which is closed with the bumper energised, is a normal 'matrix' switch, and simply registers a score, triggers a sound effect, maybe alternates other features, etc, etc. This would be why you're probably not seeing a 'Test Report' concerning the bumper switch. Though in fact, in the close-up picture, I think the longer blade of the 'scoring' switch should be above the fibre linkage, and adjusted so that it 'follows' the linkage as the bumper operates, i.e. the linkage holds the contacts apart with the bumper at rest.

The special switch operates the coil drive circuit by connecting the switch wire coming from the driver circuit on the Cpu board to ground. Each such switch should have the resistor and blue capacitor fitted. They serve to prolong the driver pulse from the circuit, and ensure a good kick from the solenoid. Brown-Black-Brown is 100 ohms (1, 0 for value and 1 zero added), it looks like 1/4 (0.25)W power rating.
 
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There's no bodge!! My black knight has excactly the same thing on all 3 bumpers,have you got a schematic gaz
 
But the black wire shown in the first picture isn't how it should be is it?

The manual (and chart above) suggests it should be a 'Blu/Grn' wire going to the coil on the left pop bumper?
 
No mate, the bodge is on the coil wiring to by pass the switch matrix.
Yes I have schematics. I can happily reinstate everything once I get those resistors and capacitors.
 
If it's anything like firepower it is ment to be there it's a special switch set up that williams used on some pops. I may have one of them resistors but they only cost pence to buy
 
Thanks Rudi. I appreciate they are pence. But if someone has a stack of them, id rather pay for a first class stamp and a couple of quid rather than order on line and pay £5 postage and trawl the Internet for something I have no idea what I'm looking for!!
 
Thanks guys. I'll have a look at the colours tomorrow. When I get that, if somebody would be kind enough to spell out in toddler terms what the values of the resistor and capacitor are and where I can get them, I'd be much obliged.
 
The manuals for games that age don't show the wiring for special solenoids and switches, but those for older games, such as Firepower or Black Knight, show the resistor as 100 ohm, 0.25 W and the capacitor as 22 microfarad (uF), though the voltage isn't stated. Check on the one you've got for the voltage rating (I can't quite see it in the picture) and take it as a minimum. It's an 'Axial (lead at each end) Electrolytic (polarity sensitive) capacitor.

In fact, even the small 'handbook' for the older games has a drawing showing example wiring for special solenoids & their switches.

When you dig out the proper lead for the bumper coil (the solenoid chart says it's Blue-brown), be wary of the results with it re-attached to the coil. The drive transistor (Q75) could well be short-circuit, and the original cause of the coil being bodged.
 
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Fantastic thanks very much Jay. The driver transistor was toast as the coil locked on and burnt out so that's been replaced anyway
 
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