[Solved] Asteroids Deluxe G05-805 Monitor Madness

scintillating noises
Maybe it's just different in person than in your video but that just sounds like yoke chatter to me. I popped open my AD cabaret and the yoke on my monitor sounds about the same. Vector yokes aren't like raster yokes that just make one continuous whine. The noise a vector yoke makes will vary a lot depending on the image being produced.
 
I think the amplifier is drowning out the sound from the yoke. I'm going to pull the deflection board and uncap C603 and C703 like andrewb was suggesting, and take a close look at the the HV cage to make sure I didn't make any soldering errors when I recapped that.
 
Ok. That's much better. The purple stuff that I saw is a reflection of your overhead lights or of some LED strips or something that is slowly color cycling. That's why anytime you're trying to show a video of the CRT neck, you need to record it with the lights in the room lights turned off.

Anyway....that looks and sounds normal.

The orange glow is from the filament heating up (just like an incandescent lightbulb). It's normal and correct.
The sound is "vector chatter", caused by the deflection system. It's also normal and correct.


Respectfully disagree. Something is wrong here. That sizzling sound is more than just chatter. He also had chatter before, as he's had XY deflection the whole time, the root cause from the beginning has been a Z issue. So if he's hearing a new sound, it isn't chatter.

Also, to my eye that neck glow is MUCH brighter than it should be. It's nowhere near that bright on my AD. It almost seems like a tube issue, however I suspect and hope that's not the case, and it's just something else that got messed up when he did the cap kit, since it wasn't sizzling before that.

@SpellboundLogic, remove C603 and 703. If they are backwards, that's going to cause problems. (And if they were installed backwards, they're going to be damaged, as you can't install electrolytic caps backwards.) Those caps aren't needed anyway, as they were removed on later versions of the board. So just remove them.

I think you have multiple issues going on here. I still think there's something wrong with your deflection board, which is affecting the Z signal. (Potentially the spot killer circuit, or the Z circuit itself.) Plus if those two caps are backwards, that's going to be a separate issue.

However from your video, your HV is also too low. You can tell that from the fact that the picture is very bloomed/zoomed in, which you could see for a second when you turned up the brightness.

You capped the HV cage. However the thing that actually causes more problems on these is the HV diode contacts being dirty. I have a long post about this here. This is the most likely cause of your low HV.

Fixing that is something that all cages need. At a minimum this requires disassembling the diode/boots/springs, and cleaning the boots out with acetone and Qtips, to get all the dried grease out. Then you should solder the springs to the diode. This is tricky to do because the springs are steel, and requires good solder, a good iron, and everything to be clean bare metal. But it's the best way to fix it permanently and prevent the problem from coming back. There are some tips in my post above.

Note that your HV diode may also be bad, which can happen if these are run too long with dirty contacts. 95% of the time they are still ok, but you won't be able to know until you clean the contacts and test the cage again.

At this point, you may just want to send the deflection and HV in. I can refurb them both for you if you want.
 
Respectfully disagree. Something is wrong here. That sizzling sound is more than just chatter. He also had chatter before, as he's had XY deflection the whole time, the root cause from the beginning has been a Z issue. So if he's hearing a new sound, it isn't chatter.

Also, to my eye that neck glow is MUCH brighter than it should be. It's nowhere near that bright on my AD. It almost seems like a tube issue, however I suspect and hope that's not the case, and it's just something else that got messed up when he did the cap kit, since it wasn't sizzling before that.

I don't know. Could be. But to me it just sounds like deflection is cutting in and out. I've had that same thing happen before. It's hard for me to gauge how loud the sound is, because there are too many uncontrolled variables in the recording process. But most "gross" sounds will appear to be louder if they are intermittent.

That neck glow looks a lot like my old Asteroids monitor. Different monitor I know, but it's VERY simliar looking. The voltage and current checked out, it was just extra bright. Same tube too: 19VARP4. The tube was in very good condition (measured with a tester) and it ran nicely for years before I sold the machine. I don't remember for sure what my several AD monitors have looked like. It was a mix of -802's, 19V2000's, and a 15V2000. I think the 15V2000 is a little brighter than the 19" models.

Easy enough to check the heater voltage. Measure the AC voltage at the pins. IIRC, if you measure it at the CRT pins it should be around 5.6 VAC depending on what your mains voltage is.

I do agree there is a problem on the deflection board. At the very least something in the Z- section and/or spot killer. But maybe is there something causing the deflection itself to be intermittent? That could then cause the spot killer to activate? Just thinking out loud here.

And yes, that HV is suspect too. Gotta service the diode for sure. The diode itself is most likely fine. Just the connections to it are bad. Fix that first since it's an easy fix and it will eliminate a host of secondary problems. Andrewb describes that repair process well.
 
I want to conclude this by saying that there was nothing wrong with the EHV cage or the deflection board. This was caused by two loose pins on the molex connector that plugs into the monitor assembly from the PCB.

I am as gobsmacked as anyone, after replacing caps, transistors, and thoroughly cleaning the HV diode, boots, and cups. Thanks to everyone who helped me to troubleshoot. Sometimes it's the simple things.
 
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