Newbie pinball help - Stern left flipper. ta-100 rectifier? driver? or ?

yellowstitch

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Newbie pinball help - Stern left flipper. ta-100 rectifier? driver? or ?

picked up a pin not too long ago. Now I am 100% new at pins, I have never even touched the inside of one until now so any help would be awesome. the left flipper does not work. Did a continuity test from left switch to driver and from driver to coil and was all good. what could the issue be? the rectifier board is all chopped up and ran to the back of the board. could that be it? I did connect the green left flipper wire to the right flipper coil and nothing happened. any ideas? right one works fine and as far as I can tell so does everything else. here are some pics thanks in advance

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klovp2.JPG



klovp3.JPG



klovp4.JPG



klovp5.JPG
 
Hard to tell if it's wired properly from the picture but I can tell you that it's most likely not going to be a rectifier board issue, given that the other flipper is working. Someone could have run a dedicated wire to that flipper from that board which has not come off making me a liar but I doubt it.

The first thing to do is check for positive voltage at the coil with the game on. Then ground at the coil with the cabinet switch closed and the game ready to play. If you don't have one of those the coil will never work. If both of those are present then it's probably not wired correctly but I'm guessing it's most likely a power problem.

The positive voltage will be coming right off the rectifier board. The ground will go from the rectifier board to the regulator/driver, through the flipper relay and out to the cabinet switch which will supply the ground to the flipper coil. That's a basic overview.
 
I picked this one up off of Yellowstitch at MGC last month. I didn't know this until I was combing Google for "Stern left flipper issue" and this post popped up. The power of the 'net!

Anyhow, finally got to it today. I replaced the rectifier board with one from Great Plains Electronics & repinned the connectors, repinned the connectors and swapped out the MPU with an Alltek that I had because the MPU had corrosion from the NiCad battery, rewired the flippers per schematic and switched out that Williams coil. Still had no luck geting the left flipper to fire.

I took the SDB out of a working Bally SS that I have and voila: working flipper, happy wife (she loves this game for some reason). So now that all of that's out of the way, where do you guys suggest I look on the Stern SDB for the flipper problem?
 
The relay on the far left in the middle. that activates the flippers. Maybe it's bad and only one of the flippers gets activated.
Also check the connector below and above it - the 2 wires on the top of the connector below, and the 2 wires at the bottom of the connector above it, go to the flippers..
 
Thanks! Upon further inspection, it seems like the traces leading to the relay at K1 at one time burnt up and there are jumpers out in. I'm gonna see if I can reflow the solder and fix it. Perhaps there's a short there since one of the flippers does work?
 
Fixed! I had to jumper the burnt trace from the relay to one of the pins on J1.
 
Fixed! I had to jumper the burnt trace from the relay to one of the pins on J1.

It may be working but is far from being fixed.
You have several rectifier board issues that must be corrected before you burn that board up.
Replace power resistors (they're toast).
Replace connector set (they're turning to toast).
First bridge rectifier not screwed tight to heatsink -- that bridge generates a lot of heat. Good, tight connection for him is important.

SDB been modified to eliminate floating grounds (see pinwiki)?

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...nevermind. Didn't notice the post about replacing the rectifier board until after I hit send.


Ed
 
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