PE 1492 Dead Video Board - No Pic

[Gunk]

Have a PE w/1492 video board and no pic.  CRT has hard burn in.  After some research I reached out to Chris-socal for an assist.  We thought it would beneficial to create a thread to share.  I explained the issue via PM but cannot recover what I sent.  In essence, it was just about a dead 1492 board and possibly CRT.  I have a capacitor kit I'm planning to install.  Chris-socal responses are as follows.  We'll use this thread form this point forward to continue the conversation:

"There aren't that many caps on a 1492. There are 4 that are absolutely critical and will hold the board in shut down if they are out of tolerance. 286,233,230,191.  The board will typically start if any of the other caps are out of tolerance, the image might be messed up but they don't stop it from booting.
There is also a 10uf 16v surface mount cap on the PRA-H board (214) that needs to be tested. If you have unresolved image issues it is suspect. If they test bad we remove the surface mount cap and replace it with a regular radial cap. Looks funny but works great."

"Highly doubtful it's the tube. If the tube has worn out you would still hear it energize when the flyback kicks in. If the board is being held in shut down you will get nothing from the tube. This is what I think is happening.  Based on your symptoms I'm going to guess one of those caps is holding it in shut down. XRC5184 has one job, monitor all the power consumption, if anything is out of tolerance it holds the board in shut down. You will often hear it chirping either fast or slow, it's not loud, just like a little chirp noise coming from the power unit next to the flyback."

"If you do decide to install your own cap kit be sure to discharge the anode cup. You can find instructions on youtube. Personally I clip a wire to a screwdriver. Clip the other end of the wire to the chassis then slip the screwdriver under the cup while holding only the plastic handle of the screwdriver of course. In your case nothing will likely happen but you have to be sure it's discharged. Ceronix flybacks self discharge but I have seen a few that didn't discharge quickly and I would have gotten zapped."

"It isn't abnormal for the flyback to turn brown or develop cracks on that square face panel, they often leak HV in that are so use needle nose pliers. Chances are the lower knob has red loctite on it anyway so don't mess with it. I still say the board is in shut down from Caps. Out of all the boards I look at more than half are just cap kits and/or a bad solder connection somewhere."

[Chris-socal]

Im adding the photo you sent me, there has been a lot of trace repair. As you mentioned 291 and 207 look suspicious/missing. All of those traces need to be toned out with a meter to verify continuity.
If there are this many trace issues around Vertical section I suspect there are issues around the PRA-B color boards and the transistors around them. The only way you can spot them is to look closely through a magnifier.
I suspect this board is a later production run, they had more trace issues.
Also, look a the yoke connectors 2 and 3. Someone reflowed solder, which is fine, but were they look awfully close, make sure they are not touching.


Chris

[Gunk]

IT's ALIVE!!!  Thanks Chris-socal, cap kit did the trick.  Definitely have a couple of traces to repair and need to sort out how that's done.   Vertical sizing (VSize) doesn't work but suspect that's one of the traces.  Thanks!

[Chris-socal]

Congratulations.

Yes, those traces around PRA-H can cause that and also that 10uf capacitor on PRA-H. You also need to check all the traces on the connector that goes to the report board on the top of the tube. Those solder joints go bad too. I would probably re-flow 75 or more solder joints if I had that board on my bench. Some of those  repairs are done as I would do, use a leg from one of the capacitors as a jumper....but only use a component leg if you are not jumping over another trace. If you need to jump over another solder joint or trace you need to use an insulated wire.

Good luck and keep us posted.

Chris

[Gunk]

Thanks Chris, will do.  I like to tinker but if/when I fail, the board is coming your way.   

[Gunk]

Thanks to Chris-socal for his sage guidance.   I'm pleased to report after replacing all the capacitors, I found three bad traces and jumped them with insulated wires.  I also resoldered the points that I thought might impact VSize.  The video portion of the machine now works great.  Now on to the buttons, coin device, etc. Thanks again!

[jay]

Great news - Please start a new thread for the rest. We can keep this one around as a good guide to 1492 trouble shooting and repair.

[Gunk]

Will do Jay , thanks

[Chris-socal]

Yes, my title would be:

Traces, Capacitors, Traces, Capacitors, dry solder joints….and traces. And capacitors.


Then I would say: And get a magnifying light, even if you are 20 and have great eyes. Fellow member Justin finally succumbed to my hounding and put his board under a microscope. He found broken traces.