TAF Lock-On Problems

wxforecaster

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Sigh. My TAF has been one of my most stable machines in the 11 years I've had it -- until today. In preparation for our Super Bowl party next week, I decided to do some pinball maintenance -- clean the glass, check through the test for any bad switches, bulbs, etc...

After replacing a couple pf burnt 44s in Addams, I decided to play a couple games. On the second game I registered a Thing multiball, except when the ball landed in the saucer nothing happened. Namely because the eject was already in the "kickout" position.

I turned off the game and it immediately retracted. Turned on the game and it immediately fired. However, I also heard a loud hum coming from the center of the playfield, and after about 15 seconds of searching and noticing that old familiar burnig smell, noticed the left magnet was now also locked on.

Am I just having a REALLY bad day? This seems far more than coincidence that the thing eject outhole and the left magnet would both lock on, but I suppose just the act of firing on a machine of this age can zap some TIP102s or TIP36Cs.

As far as I can tell there are no links at all between the outhole and magnet, but I just can't believe that two transistors would blow almost simultaneously.

Outhole/Sol 5 - Vio-Grn - J130-6 - Q64
Left Magnet Brn-Gry - J127-9 - Q44

Figured I'd get a second pair of eyes on this before I begin taking the boards off.

Evan
 
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Crap happens.

Fix said crap.

The magnet transistors are mounted under the playfield nearby, and a real common fail item on TAF, hence a lot of burned playfields out there.

Pinballlife.com sells a simple easy to install fuse kit for the magnets, I'd strongly suggest adding it.

LTG :)
 
I just had a similar magnet lock problem. (came out of nowhere) A chance you need to fix the tip36c underneath the playfield and the TIP102 on the driver board. I just posted to RGP about 2 weeks ago.

Good luck.
 
Well, one of the TIP36c's beneath the playfield was indeed bad (and interestingly enough not original).

Unfortunately, I'm all out (sigh) and waiting for a friend to return home so I can bum a few back from him. Then onto the 102s.

Two hours later and the basement still has that nice burn smell to it.
 
Splattergatz,

I'll shoot you a PM. Mark didn't have any left either (looks like I'll have to place an order), but I need a few 36c's to get these games up and running before Super Bowl Sunday.

Evan
 
Alright, replaced TIP36c (stolen from extra fliptronics board) at Q3. Magnet fixed.
Decided to pull off the main driver board to address the thing eject hole lock on.

While I was there I decided to test all the driver/pre-drivers. Sure enough, the only one that tested bad is Q24's right leg (0.17V) which is the Thing eject hole.

Unfortunately, it was during this process I noticed that my G.I. connector was burned to a crisp on two of the pins. I've already done a couple of these and not looking forward to the crimping with my arthritis :( Oh well, it must be done.

Evan
 
Alright...

Q3 on the magnet board under the playfield fixed that
Q24 fixed the thing eject hole.
Repaired the burned connector at J115.

Even before this began, I noticed that half of the bulbs in the backbox didn't illuminate. This non-working set (the house) and the other working set (the people) both go to an 11 pin connector at J120, with only 2 pairs of wires for each set.

Here's the odd thing. If I measure the AC voltage at the pins I get ~7V for pins 3/9 and ~7V for pins 4/10 ... perfect.

As soon as I apply the connector (which runs DIRECTLY to the lamps in the back box), I get ~5.4V for the working people with lamps illuminated, and 0V for the non-working house. I am stumped at basic electricity here. I get continuity from the connector to the terminus of both wires (white/orange and orange), and I seem to have continuity across each bulb socket.

I'm certainly not the smartest person in the world, but what the heck. Is this like "Clark Griswaldian" where if one bulb is bad the whole string goes out?
 
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