F-14 Tomcat GI torture

Hi folks, first post here.

I received an F-14 in less than ideal condition.

As such, I've been slowly going about obvious repairs and some upgrades.

Recently I began having problems with the slings and pop bumper, and this forum has been great to drive home where to look.

Having gotten the pop and slings to work, I quickly took notice that I no longer had working upper GI and pop lamps working. Yes, the F1 violet white fuse was blown. I can reliably reproduce that at this point.

I've been trying to eliminate large sections of the playfield and am starting to get discouraged.
I've desoldered violet/violet white for the pop bumper, the switch for what I believe is the spinner at the bottom right of the playfield (with it standing up and the guts facing me), the staples playfield traces for lamps in the same vicinity, and also disconnected a plug that terminates into new colors for the upper PF. Yes, the IDC connector on the power board had some black char. I've temporarily hacked that with some PC molex connectors.

I can reliably disconnect 3PJ and 3P8 and not blow a fuse, so I believe this means that my issue is in the playfield, somewhere.

At this point none of the PF GI is working, however the lower half briefly did after adding the molex connectors in the mix.

I'm targeting violet and violet white, and thought I'd reach out to some smarter gents before I disconnect anything else.

Any help is greatly appreciated.

#2 5 years ago

DAV

wayout440

Pinside member

I assume you already pulled all the bulbs, correct?

At that point I would cut the GI approximately in half under the playfield and use an ohmmeter to find out which half of the circuit to look for a possible socket problem. Possibly dividing it further if need be. (Divide and conquer troubleshooting method)

#3 5 years ago

ELD

darcangeloel

Pinside member

Richmond, VA

7y 66,800 915 4

Quoted from wayout440:
I assume you already pulled all the bulbs, correct?
At that point I would cut the GI approximately in half under the playfield and use an ohmmeter to find out which half of the circuit to look for a possible socket problem. Possibly dividing it further if need be. (Divide and conquer troubleshooting method)

This is a really good idea and something I do all the time. Not long ago on my pinbot shop job I somehow dripped solder into a molex and was causing two rows to short together (They would trigger at the same time no matter what switch was pressed). I unplugged all the pf items that had molex connectors and the issue went away. I then inspected each of them and saw where I had accidentally connected the two hahaha. Using the method way out described will save you a bunch of time.

#4 5 years ago

???

kinggoo

Inactive member

This was hard to track down with the traces and changing wire colors. It ended up being a solder ball short - bridging leads on this guy.

Screenshot_20181112-213236_Chrome (resized).jpg

#5 5 years ago

DAV

wayout440

Pinside member

Good find!

#6 5 years ago

???

kinggoo

Inactive member

Quoted from wayout440:
Good find!

Thanks!

I'll check directly underneath where I drop solder next time. Or not drop solder. One of the two.

Onto trying to figure out the beacons and Yagov kicker again.

#7 5 years ago

DAV

wayout440

Pinside member

OP
Quoted from kinggoo:
Thanks!
I'll check directly underneath where I drop solder next time. Or not drop solder. One of the two.
Onto trying to figure out the beacons and Yagov kicker again.

What problems are you having with those?

#8 5 years ago

???

kinggoo

Inactive member

Quoted from wayout440:
What problems are you having with those?

Yagov kicker hasn't worked* since I got it. *worked for one game when I was trying to follow vio-wht wires and reseated the connector at the bottom left side of the playfield where it runs into a group of diodes and changes colors. I assume some retermination is in order.

Beacons/light only work when I touch wires between coil and ground on the relay. Rebuilt the snubber relay board with a new relay - same result. Relay clicks, and no love. Fuse is good.

#9 5 years ago

DAV

wayout440

Pinside member

OP
Quoted from kinggoo:
Yagov kicker hasn't worked* since I got it. *worked for one game when I was trying to follow vio-wht wires and reseated the connector at the bottom left side of the playfield where it runs into a group of diodes and changes colors. I assume some retermination is in order.

So, the problem is you have no DC power measurable at the Yagov coil, correct?

OP
Quoted from kinggoo:
Beacons/light only work when I touch wires between coil and ground on the relay. Rebuilt the snubber relay board with a new relay - same result. Relay clicks, and no love. Fuse is good.

Does it work or not when you jump white/blue to white/blue at these points to the relay?

untitled (resized).jpg

#10 5 years ago

???

kinggoo

Inactive member

Quoted from wayout440:
So, the problem is you have no DC power measurable at the Yagov coil, correct?

Does it work or not when you jump white/blue to white/blue at these points to the relay?[quoted image]

Re: Yagov - I will test this.
Re: Beacons - It works when I jump white/blue to white/blue.

#11 5 years ago

DAV

wayout440

Pinside member

OP
Quoted from kinggoo:
Re: Yagov - I will test this.
Re: Beacons - It works when I jump white/blue to white/blue.

OK, then that leaves the relay itself, or the triggering of the relay. Earlier you said the relay clicked, which should turn on the beacons unless the relay is failed.

Ground the tab with the brown wire at the relay. The relay should click and the beacons run. If it does not - relay is bad or miswired. If it does, ground MPU board pin 1P12-9 (brn/gry) and see if it runs.

#12 5 years ago

???

kinggoo

Inactive member

Quoted from wayout440:
OK, then that leaves the relay itself, or the triggering of the relay. Earlier you said the relay clicked, which should turn on the beacons unless the relay is failed.
Ground the tab with the brown wire at the relay. The relay should click and the beacons run. If it does not - relay is bad or miswired. If it does, ground MPU board pin 1P12-9 (brn/gry) and see if it runs.

Relay clicks for both tests. That is all.
1J12-9 FWIW.

#13 5 years ago

???

kinggoo

Inactive member

OP
Quoted from kinggoo:
Relay clicks for both tests. That is all.
1J12-9 FWIW.

Update: I had replaced the relay, and the trace leading to coil from the relay basically lifted up with very little disturbance. Upon looking at it tonight, I had soldered in a wire to bypass the trace, and it was loose from the coil pad. I only looked closer after measuring ACV from coil pad on the relay to fuse clip and not seeing anything during coil test 16. I know I had ACV here pre-relay replacement, which made this all the more confusing. I have beacons!

Now if I can fix Yagov without tearing the diverters and ramps apart I'd be sitting pretty.

Post last edited 5 years ago: “Updated coil test integer”

#14 5 years ago

DAV

wayout440

Pinside member

OP
Quoted from kinggoo:
Update: I had replaced the relay, and the trace leading to coil from the relay basically lifted up with very little disturbance. Upon looking at it tonight, I had soldered in a wire to bypass the trace, and it was loose from the coil pad. I only looked closer after measuring ACV from coil pad on the relay to fuse clip and not seeing anything. I know I had ACV here pre-relay replacement, which made this all the more confusing. I have beacons!
Now if I can fix Yagov without tearing the diverters and ramps apart I'd be sitting pretty.

Good job! Before you take anything apart for the line of death kickback, get your voltmeter on CPU pin 1P12-5. The solenoids at rest should have something near the solenoid DC voltage all the way through the circuit. Obviously the power side should have it, but the coil is basically a giant spool of wire with low resistance. So when no current is flowing, the same voltage is also present on the trigger side and all the way back to the CPU firing transistor. If you have voltage on this pin 1P12-5, that verifies all the wiring is good. You can briefly ground the connector pin with a jumper on top to see if it fires. This will tell you if you *might* have to take apart the playfield or not. You can also ground Q8'S metal tab, but just keep in mind that also tests the portion of the CPUI board from the transistor out to the connector on the board.

#15 5 years ago

???

kinggoo

Inactive member

Quoted from wayout440:
Good job! Before you take anything apart for the line of death kickback, get your voltmeter on CPU pin 1P12-5. The solenoids at rest should have something near the solenoid DC voltage all the way through the circuit. Obviously the power side should have it, but the coil is basically a giant spool of wire with low resistance. So when no current is flowing, the same voltage is also present on the trigger side and all the way back to the CPU firing transistor. If you have voltage on this pin 1P12-5, that verifies all the wiring is good. You can briefly ground the connector pin with a jumper on top to see if it fires. This will tell you if you *might* have to take apart the playfield or not. You can also ground Q8'S metal tab, but just keep in mind that also tests the portion of the CPUI board from the transistor out to the connector on the board.

Getting ready for deer season, so I only had a chance to test grounding 1J12-5 to ground. I hear a relay click and that's it. Sounds familiar. I will get back to this in about a week, but is there any current day manufacturer of these boards? I'd prefer to not hack them with wires or reinvent the wheel and such, but I do have extra relays.

3 weeks later

#16 5 years ago

???

kinggoo

Inactive member