Monitor issue

[Yakama]

Firstly does anyone know what model this chassis is?

When it arrived it was dead, a few cracked solder joints sorted and now it starts up but the image is kinda washed out and shadowy, it’s also sometimes distorted somewhat. I will recap it and hopefully that sorts it but if anyone has any other ideas?

It was very clean and doesn’t look like it’s been touched before. I don’t even think it has been taken off the tube before

 

[Flyback2021]

Looks like a k7000 Wells Gardner

 

[Yakama]

Thanks

 

[NLjevader]

Firstly does anyone know what model this chassis is?

When it arrived it was dead, a few cracked solder joints sorted and now it starts up but the image is kinda washed out and shadowy, it’s also sometimes distorted somewhat. I will recap it and hopefully that sorts it but if anyone has any other ideas?

It was very clean and doesn’t look like it’s been touched before. I don’t even think it has been taken off the tube before

It looks like a Wells Gardner k7000 chassis for a 25" tube ( 25K7000 ) 😇

 

[Yakama]

Also should this auto degauss as it doesn’t seem to and I can’t find a button anywhere. There was one in the machine with the coin counter but it doesn’t seem to do anything when pressed

 

[tb2000]

Try turning down the blue cutoff pot or the blue gain pot on the neckboard. They don't have an K7000 chassis don't have a button for degauss (I don't remember ever seeing one anyway). If it's not auto degaussing you need to check that part of the chassis over.

 

[NLjevader]

It looks like a Wells Gardner k7000 chassis for a 25" tube ( 25K7000 ) 😇

Sorry for the double post, had to refreshed the page first

 

[Yakama]

Try turning down the blue cutoff pot or the blue gain pot on the neckboard. They don't have an K7000 chassis don't have a button for degauss (I don't remember ever seeing one anyway). If it's not auto degaussing you need to check that part of the chassis over.

Thanks ok will have a look at that then

 

[Yakama]

Adjusting those pots doesn’t seem to help

 

[tb2000]

Hmm, it might be a leaky transistor on the neckboard or on the chassis then in the blue circuit. Are either of the pots cracked? Also, just noticed the start of the sentence I typed above about the degauss doesn't quite make sense!

 

[Yakama]

I will check tonight. Thanks

 

[Yakama]

So after giving all the pots a good clean with ipa the monitor now looks much better. I’m waiting on caps to recap it then it needs a bit of setup. I can’t get it to look sharp with the focus adjustment yet but it’s such a massive machine im having to adjust round the back then check round the front and I’m finding it difficult to set that way. But overall it’s looking much better and is now at least playable.

Next is to sort the cracked wood, replace the worn out buttons and then look at getting a new control panel overlay made up

 

[Yakama]

Oh and the thermistor for the degauss has a big crack in it so think that’s why that isn’t working. A new one has been ordered so hopefully when that arrives I can fix that too

 

[tb2000]

Can you position a mirror so you can see the front of the screen whilst you're round the back of the cab? You may find the focus pot is going bad, that lopt appears to be an original as fitted at the factory. They often get hairline cracks in the case due to age, and sometimes you'll get one going right through the focus pot area which nearly always affects the way the pot works. If you can't get the focus set or it drifts once set you'll need a new lopt.