Hey guys,

I'm relatively new to system 11 as this is my first one so sorry if these are dumb questions! I'm having a couple of issues with my F-14 Tomcat that I can't seem to figure out, I was hoping to get some ideas here.

1. I get occasional resets where the LEDs dim and the game will reset and come back to life. I've tested 12v on the main board on the "12v Unreg" point and actually get anywhere from 7-10 v off of it, so I'm assuming something is wrong with the psu board. I've ordered a cap kit because of this and hopefully it'll fix it, but cannot find the high voltage kit that Great Plains sells and has had out of stock for months. Any ideas on where to find that?

2. A couple of my switches are being very lazy (though I'm not sure if there's a better term for it). Basically the right center switch the ball drops into (pictured below) after being launched will sometimes just sit for 5-10 seconds before actually doing anything. Could this be power related, or something else? The switch works and I have tested it. I tried replacing the CPU epromms for the hell of it just to see if it was something weird with the cpu.

3. The other switch doing this is the gutter switch, the ball will just sit in the gutter sometimes for 5-10 seconds before moving onto the next ball. I have also verified this switch works.

4. The final thing I've noticed is that one of the ceramic resistors has fallen off of one of the lamp driver boards. Do I even need to fix this if I've switched to LEDs?

Thanks for any help!

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1. It's just these two switches.

2. The attached photo is the board that had the resistor fall off. It was a 10w 330ohm ceramic resistor (the same one on the bottom of the board in the pic). The actual location of this board on the playfield is the right side of the playfield, about midway up, but I can get more info if need be after I get home tonight. I wasn't aware I needed to remove all of these when I moved over to LEDs, so I can take care of that this weekend. It sounds like after my Googling that the one I need to remove from all the boards is actually the one that fell off.

3. I don't think it's a tilt reset as all the lights dim when it resets, but I can play with it some more tonight and test it out. Basically I'll be playing and the audio will stop and the lights will dim, then a second later it'll go back through the startup and go back to normal operation.
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Ah thanks guys. I'll test out all the switches and see if I can track down a bad diode. I found another post that references src6 as a failure point that can cause resets, so I'll look into that as well. Looks like I need this guy to do that fix: https://www.digikey.com/product-detail/en/4610X-101-102LF/4610X-1-102LF-ND/1089168

As for my 12v levels, that does seem very low, right? Is there a better area to probe for values instead of the 12vunreg point on the main board?

Well shit...totally missed that! Recap it is haha. I'll still test the diodes tonight. Hopefully it isn't an issue with the transformer as that'll become a far more expensive fix....

I went ahead and removed the warming resistors (well, removed the ground from all 7 boards), the lighting on the game is much different now haha, I hadn't realize some of the flashers were not supposed to be on when they were on.

I've tested a few diodes in regards to the lazy switches and haven't found any bad ones but i went ahead and replaced the diode on that specific switch and have not seen the issue yet, though it could be a coincidence so I'll keep trying it.

I've also started noticing an inconsistent issue where the first ball will have no audio, it's quite strange... I'm not sure what's going on there. Hopefully it's just a power thing and the cap kit will fix it. If not, maybe time for new sound epromms?

So I feel like an idiot...the gutter lazy switch wasn't actually lazy. The spring pulling the kicker back actually was disconnected so the balls couldn't reliably hit the switch. I couldn't figure out where exactly it connects to, so I sort of rigged it. It works now, but does anyone have a picture of the gutter kicker assembly so I can see where the spring goes? I couldn't find anything when googling.

Yes it is! Interesting, I didn't know about that.

So I recapped the PSU and then started seeing constant blowing of fuse F5. I broke out the manual to take a look and saw it's supposed to be a 7A fuse. The previous owner had put a 1/4a on that spot. So once I switched to a 7a it ran as expected. I haven't seen a random reset since doing this + the recap. So everything now appears to be working as intended!

Sorry to bump this...but I guess the recap didn't actually fix it and must have just been coincidental. I continued troubleshooting and just replaced the 2N6057 transistor and yet the resets keep happening. I managed to get a video of it happening, it happens right around 25 seconds:

The game reboots abruptly. Is there anything else I should be testing? At this point I may just order a rottendog psu.

So I went ahead and replaced both of the diodes on the left flipper, I haven't seen a reset yet, so that's something. One thing I failed to mention in the last comment is that my +12v is still very low after replacing the transistor and doing a cap kit. It comes in at ~9.5v coming out of the connector on the power supply, this is what I think is causing my resets but I'm not sure what else on the PSU should be replaced to attempt a fix.

5v is holding very steady at 5.1v and did not dip below while I was monitoring it.

For me the switch issue ended up being due to a bad diode on the switch, after replacing it I haven't had it happen since.

I've gone ahead and ordered a replacement bridge rectifier (GBPC3504L), fingers crossed...

Well I got the replacement bridge rectifier tonight and uninstalled it. +12v still reads ~9.5 everywhere I test. I played for a bit and didn't have the random reboot happen, but even so shouldn't the 12v be higher? Even the manual states +12 being under 10.5v will cause issues. I'm not sure what else to try as at this point I've replaced every major part on the PSU.

Not to sound like an idiot but where are TP3 and TP4? A few threads I've come across mention them yet I don't see them labled anywhere on my board nor mentioned in the manual.

Alright so:

Tp3: 9.11
Tp4: -14

Hm I can't seem to get a reading. It jumps all over the place, it might be because my multimeter is auto ranging without any sort of manual setting. Or I'm an idiot and testing it wrong. I can pick up a better one tomorrow to see if it's just my meter not adjusting properly.

Both test points were doing it, I'm going to assume it's due to it not properly autoranging. I'll pick up a better one tomorrow and report back.

I also went ahead and ordered one of the Rotten Dog power supplies. If I still can't get this fixed soon then that'll at least tell me if it is the power supply causing the resets. At the very least it'll be able to serve as a backup once this one is fixed.

Well this is strange, the new multimeter will briefly take an AC reading before dropping down to ~.2

TP3 = 12.2
TP4= -14.4

DC it also is getting a slightly higher reading on the 12v line at ~10.1. It also seems to be resetting more since replacing the bridge rectifier. I can't even get a full game in without a reset.

Yeah, after seeing this AC fluctuation happen I'm wondering if it's the case. I'm going to replace all the solder on the connectors today and see how that goes. I'll order totally new headers as well and replace those if this fixes the issue, but for now I want to see if that's the problem so I'll at least reflow them.

On the plus side I've finally bought a True RMS DMM

Thanks for the help so far. It's interesting that it has gotten worse after I replaced the BR as well. Either way I'll reflow all the headers today and see what happens. The Rotten Dog PSU should be here Monday so that'll tell me for sure if it's a psu issue, then once I fix the stock psu I can have the Rotten Dog psu serve as a backup.

Are there any parts on the CPU board that could be causing the reset, aside from a poor connection? If so, I can just proactively replace those as well.

Well that's interesting, I replaced all the solder on the pin headers and now the voltage is sitting at 10.55 on +12 and -12.22 on -12. So that's better. So far no resets but I'll keep playing.

Sorry, this is DC voltage on TP3, AC voltage is unchanged. But now the CPU board 12v line is getting 10.5 as well, which is a huge change from the 9.1ish it was getting before.

AC isn't any different with the new meter after reflowing the pin headers. There is an initial spike for less than a second, then the meter settles around .2 and -.3v respectively.

It does seem like a lot of the problem was due to a crappy connection, though I'm not sure if it's possible to get the +12v line closer to 12 rather than 10.5.