G05-801 ghosting really badly

[David Jenkins]

I have an asteroids cab with really bad ghosting on the screen is this normal? I'd expect it to have some but this seems ridiculous. It's worse than what comes up in the picture. The monitor has been recapped and the brightness and contrast knobs don't help with the ghosting unless the image is too dark to see. Is the tube just being funny cause it's old is this a common thing is it the HV or the 4 small knobs on the deflection board? I really don't know at this point. First photo is when it's on I'm attract mode and the second is what I looks like right after I shut it off

 

[Arcade2007]

Not exactly an apples-to-apples comparison, but I recently got a Cinematronics / 19VARP4 setup running on a Space Wars board - and noticed a similar effect. The Cinematronics display does not have a dedicated Brightness control, but I did install a 5K-Ohm potentiometer in place of R10 (as recommended in this FAQ / guide) so that the delta between High-Intensity and Low-Intensity vectors can be adjusted.

Despite the installation of the potentiometer, I still see a lot of ghosting on the Space Wars asteroid and cannot adjust it out without adversely affecting other display characteristics.

I also notice a similar behavior on my Armor Attack - again with a 19VARP4 tube. The ghosting is somewhat muted due to the overlay.

I am curious to know - does your Asteroids have the 19VARP4 tube? If so, I am wondering if this is just an intrinsic behavior of the P4 Phosphor - even though it is classified as "medium persistence".

Edit: In full disclosure, I did replace the 7406 buffer on the monitor chassis - as it had failed and the intensity was pegged. Following replacement of the 7406, everything seems to be working nominally in the intensity control circuit.

 

[David Jenkins]

I am curious to know - does your Asteroids have the 19VARP4 tube? If so, I am wondering if this is just an intrinsic behavior of the P4 Phosphor - even though it is classified as "medium persistence".

Mine is a 19VARP4 as well. May just have something to do with the age of the phosphor or just how it was designed if so though that sucks. I don't have another vector tube to compare with and I haven't worked on a vector before so I wasn't sure if it's just a characteristic of the tube or not

 

[rlsharp1]

802/V2000 hybrid monitor

look at this thread of mine. not sure if this will help. I had some similar problems. Not so much a ghosting problem but overly bright and when shutting off. Has to be a problem in the Z circuit somewhere.

Hopefully andrewb can give you some guidance