Midway Winner IV schematic / IC identification

10-4, Ill take a pic of the image when its warmed up.. I can definitely scan those...
Ill post em tomorrow..
 
It looks like you're on your way with troubleshooting. I would like to reiterate what others have already said. The TV is definitely repairable. As long as the tube isn't necked, I am certain that every other component on this chassis can still be sourced or substituted. It might take a little time and TLC, but it can be done. I don't see a ton of screen burn, so the tube likely has a lot of life left in it. It's amazing to see a fully intact consumer Motorola set like this (including the pressboard backing!) and the entire cabinet is in excellent condition for its age. I think your dad will be very proud of you for fixing this!
 
So Here are the images of it powered on.. This image looks better than when I first powered it on... I wonder if this I replaced the 2 caps on the main pcb, because thats all I did since the image wasnt great.
The image can be seen fully but still a little dim... The pics are of it in complete darkness and the other with lights on.
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That's a great image!
I think you need only need to adjust it a little.

It looks too bright...but cameras lie.
Especially on these pure black or white Bronze Age games.
They just don't handle high contrast very well.

You can search on here for posts by me about adjusting a B&W monitor.

Here's one link with the simplest instructions:

The background should be black and everything else is white.
Remember...a dimmer white is better.
It will allow you to get proper focus and most importantly, it will prolong the life of the CRT.

If you have more questions, ask here.
 
So Here are the images of it powered on.. This image looks better than when I first powered it on... I wonder if this I replaced the 2 caps on the main pcb, because thats all I did since the image wasnt great.
The image can be seen fully but still a little dim... The pics are of it in complete darkness and the other with lights on.
View attachment 760229View attachment 760230
Honestly, this is not terrible. It looks like you have full deflection, which is great, but you have a slight geometry issue across the top. I am not familiar with this chassis, but if you haven't replaced all electrolytic caps, I would do so and then reassess the geometry. Many times, that slant or curl can be caused by parts being out of specification in the horizontal or vertical circuits.

As far is the dimness goes, the above linked post is a great place to start. Remember, brightness and contrast are two different things, and they should be adjusted in a certain order. If that doesn't help, time to check CRT health. Having a CRT tester is great to get a baseline reading of gun emissions. I would not blindly rejuvenate it, but if your gun emissions are in the bad/red zone even after a warmup period, a gentler clean/balance (name depends on the tester) can really help. The key is to only do this when absolutely necessary. If you decide to do it, only go through the process once. Any additional cycles will only result in incremental improvements and will shorten life of the cathode.
 
AWESOME! Advice... I thought I was on the right track.. I dont do this stuff everyday.. My Day Job puts money on the table and future restorations.
just to state this was my first BW restoration ever :) I will do some adjustments and Re-post the outcome,
Then I will need some new Pots for the Dials they are all shot... Not sure if some circuit cleaner will help..
Thanks
 
You need some DeoxIT cleaner. For most switches and control applications the normal D5S type works great.
The pots are always worth cleaning....just to see. Deoxit aint cheap. But it's cheaper than new pots. Even crappy ones.

Are the pots "nice" ones? The EJ types from Allen Bradley? Or are they just random pots with minimal markings?
If they are A-B Type EJ they are almost always worth keeping. Clean them and marvel at the luxury!

Post a picture of the pots and include any markings that you see.
 
10-4,, Ive got some Deoxit for sure.. I havent heard that name ALLEN BRADLEY since my college dayz programming a SLC100 trainer LOL :)
 
I think someone requested a copy of the TV set schematics... Hope this helps.. It helped me do the re-cap on the deflection board.
I tried doing some adjustments to the brightness and contrast and did not get much change at all.. It also looks like there is some double offset images as well.
Looks like the signal processing side needs to be gone thru and update a few caps. I may need to check those adjustment pots too.
 

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Here are a couple pics of the pots.. Ignore the AMI Rowe CD Bubbler in back ground :)
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Those pots are unknown to me. But that hole and those folding tabs indicate that:
1) They are not sealed and can be cleaned without opening them
2) They can be disassembled for serious cleaning.

Try to shoot some deoxit into those backside openings and slowly work the pot end to end about 20 times.
 
I think someone requested a copy of the TV set schematics... Hope this helps.. It helped me do the re-cap on the deflection board.
I tried doing some adjustments to the brightness and contrast and did not get much change at all.. It also looks like there is some double offset images as well.
Looks like the signal processing side needs to be gone thru and update a few caps. I may need to check those adjustment pots too.

Schematics are great!!

If the controls aren't having an effect they may be disabled. Notice in the schematic that the contrast and brightness controls include switch-selected pots.

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Without having the set in front of me I can't be certain, but I'm guessing that "manual" means the front user controls are enabled and "pre-set" means there is an internal pot that is adjusted by a technician and the external controls are disabled.

To test this theory try frobbing the 2 contrast pots R130 (pre-set) and R124 (manual) to see which one has a greater effect on the contrast setting.
 

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Hmm, I did not see that but I will definitely give a shot.. Ill re-post with results
 
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