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Grounding a transistor

RudeDogg1

RudeDogg1

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10 Years
Joined
Dec 27, 2012
Messages
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Location
Barnstaple, Devon
Well I've wired the knocker back up on bsd but it's still not showing up in the menu or game. Tested ohms and that was fine as was continuity from board to coil. So next stage is grounding the transistor but I can't remember if I'm doing it right have the black lead to ground, meter set to vdc and leads plugged in thusly

images.tapatalk_cdn.com_15_11_08_ef70b82c33d5b60033712c50cdc59ff0.jpg
 
You need to just attach a piece of wire to the ground strap in the backbox, and carefully and briefly touch the metal tab of a tip102/tip122 transistor (don't do it on the tip36c's!) if the coil fires, then the coil and the wiring too the coil from the driver board (including the connectors) are good. The problem would then lie upstream on the board, OR in software
 
on the coil, can you tell that one wire is thicker than the other yes?

touch your magic grounding wire onto the THIN wire on the coil and it should fire
 
Well then your quest is to find out where the break is (assuming it is wired to the correct pin on the solenoid output connector)

If its a displacement contact conector, then chances as the problem could be there
 
Rudi,

Am I right in thinking that the knocker doesn't show in the solenoid test, with a gap in the number sequence?. If so, what's probably happening is that the machine's set to use the knocker drive circuit for a coin meter instead; does it knock (perhaps repeatedly) when a coin is inserted?.

As a previous reply states, using the DIP switches (or the jumper pattern) to set Usa conditions usually stops this and brings in normal knocker use. I've heard that besides having all the jumpers intact, 'Usa' is also established by having two or more of them broken.

I used to get this with all new Williams games at the time. Since I regard a knocker as an essential part (unlike some 'ops', who seem to think it's a handy spare coil), I'd change the 'Pricing Adjustments' to 'Custom Pricing', and 'Custom Door', since I also changed the order of coin inputs. With Custom(s) set, a setting called 'Coin Meter Units' becomes visible towards the end of the pricing adjustments. Setting this to 'OFF' brings in the knocker - it should then also appear in the solenoid test.
 
I don't recall having to alter the jumper pattern to allow 'custom' settings, with choice of knocker/meter, etc. Go into the Pricing Adjustments (A.3?) and see if the main pricing scheme will let you select 'Custom' rather than U.K., France or whatever. I think the Meter Units function is more likely to come in with the door settings, though. i.e. a 'custom' door scheme sets the value of each coin input for the electronic running total(s), and the unit value for the meter, if used. In the uk it would be 0.10 for 10 pence units, while the yankees would have 0.25 for a total in quarters.
 
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