Jokerz!
Williams, 1988This one is stumping me.
We recently moved and since I have set up our Jokerz, none of the feature lights work. I am assuming something has become dislodged. I have spent a good deal of time removing and reseating connectors and checking fuses but I am lost for direction. Any help would be greatly appreciated. Thanks in advance.
First get a DMM and check for incoming +18VDC feature lamp power at 1J4. Since you lost them all this is most likely the problem. Check the big capacitor in the backbox that is to filter the lamp power. Make sure none of those wires have broken off, as well as the bridge rectifier wires. If you have DC lamp power at 1J4 then we can investigate further.
Quoted from budfrog80:Thanks for your help. I don't believe that I am getting power to IJ4 as you suggested. At the risk of sounding like a total newbie, I used an autoranging DMM on DC with the black lead on the ground and the red on the pins of IJ4. Is this correct? Thank you for any help you can provide.
Lamp ground is the black wires of 1J5. Try again. If you still don't get it, go back and check at the capacitor. Also make sure your fuse is good, didn;t pop out or break during the move. At the fuse is AC before the bridge rectifier so you will measure that differently.
wirew (resized).pngw9 (resized).pngI really appreciate your help and patience.
Ok. I haven't been able to get a DC voltage at IJ4/IJ5. I also have not been able to get an AC voltage at the capacitor. May be doing it incorrect because I can get an AC voltage before the fuse of 14.55 V. I have been reading about bridge rectifiers for the last day or so. When I place the black lead of my DMM on the positive lead and touch the red leads to the adjacent lead, I get a reading of 3.69 MOhms and nothing to the one directly above it. When I touch the red lead to the negative lead and test the adjacent leads on the rectifier I get readings of 40kOhms and 35.96 kOhms. Do I have a bad bridge rectifier?
Thank you so much. I am really trying hard to learn about my games as things need to be fixed.
Quoted from budfrog80:I really appreciate your help and patience.
Ok. I haven't been able to get a DC voltage at IJ4/IJ5. I also have not been able to get an AC voltage at the capacitor.
You are welcome. You just said AC voltage at caps, how about DC? I'm assuming this is probably no, but please verify. I'm leaning toward this bridge is probably failed based on what you said already.
It would be best to disconnect all four terminals to test the bridge. This way you will not get any interferrence from other devices.
On each set of terminals take a reading in both directions, for a total of 8 readings ( 2 reading on each diode ). The diodes will read infinite in one direction & zero (near zero) in the other direction if they are good.
SsTwJ (resized).pngjsFcp (resized).jpgdiode check (resized).pngCouple of options:
Preheat with heat gun on low carefully, then high temp soldering iron with a large tip. Can help to add solder.
Another is to use two irons,
Another option would be just to clip the connectors off and rebuild with new connectors. This is the option I would use in most cases, because it can be a pain to get the female spades on the new bridge with solder in them.
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Westlake, OH