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FluxChiller

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Hey guys, so I have a MS9 that i had recapped a few months ago and finally got around to powering it up tonight.

I think all the wires are correct but this is the issue i get

https://photos.app.goo.gl/k4Yojj3kufXZ54ccA

If i disconnect the red/blue wire that goes up to the copper bands - I then get no hiss and thin veritcal line - other wise plugged in - i get whats in the video.

Any thoughts?
 
red/grey wire that goes up to the copper bands
The copper band thing is the yoke, and those are yoke wires. One set is for horizontal, the other is vertical (I couldn't tell you which is which, the other set is the brown/yellow, or brown/white with the same style connector).

Anyway, my money is on your HOT has gone out.
 
Thanks man, I had the board recapped and this was the first test run up since i go it back- apparently it bench tested just fine before he sent it out (CRT labs). Could the HOT have just failed by random/timing? Could it be an issue with the part that attaches those wires from the chassis to the yoke? The connection there looks not that great.

Attached are more pictures - not even sure which one is the HOT.
 

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It's not abnormal for the HOT to go after a recap.

I don't see anything obviously wrong with the yoke.

Which MS9 is that, and I could probably look up the part location and part number for you.
 
Nice - will check back in when I have an update. Most likely going to hire a local guy to come do a house call. Anything you would recommend to screen/pick a guy?
 
Anything you would recommend to screen/pick a guy?
Ask around and see who else knows them, or has had them do work.

KLOV would be a good place for that. Chances are high /someone/ on there has dealt with whoever you're looking at.
 
that's pretty odd, first thing to do is read the horizontal yoke winding with a meter set to ohms- it should read around 1 ohm ( red and blue yoke wires)
ms9 will shut down within a few seconds if there are any issues in either deflection circuit

if the HOT is short then there has to be a cause, this went for service and was tested so it can't go faulty electronically during shipping- either your deflection yoke is corroded internally or the chassis was damaged during shipping

Was the monitor working before you sent the chassis for service?

your video was too brief with a screen shot to see what was actually happening
 
yeah its odd - lots of uknowns at this point. Here is the history of it so far:

So I purchased this monitor about a year ago as a "maybe" works type thing. I have a main WG monitor, but its not as close to spec/original as this one - so Id prefer to use this one. When I purchased it, it worked - although the lower horizontal 1/4 of the screen was dimmer than the upper 3/4. Both me and the seller figured it was a cap issue. Sent the chassis off to CRT labs - who recapped and verified it worked on his test bench. Got it back, very well packed and shipped - so no reason to suspect damage - but it has sat for the last 6 months waiting to go into my astro city (being restored).

So Saturday night, a group of us from this forum had a get together and decided lets at least test it, plugged it all up with no PCB or anything - just to see what it would do.

Hooked it up to a freshly recapped capped power supply and fire it up:

1. no picture at all, get static building on tube, and very high pitched whine coming from the yoke.
2. Monitor cuts off after about 4-5 seconds


Test 2:

We unhooked which I assume is the 2 horizontal plugs from the chassis that go up to the yoke:

1. We get a nice bright white line (2-3cm wide) running vertical down the center of the tube, no yoke whine, and its stable like this until we power off.

Test 3:

We unhook those "working" 2 plugs and then hook back up just the (assumed) 2 horizontal wires and power up.

1. Same results from initial power up.

Thats as far as I have gotten.

(we also switched out 2 different power supplies just to rule out that - with same results.)


Assuming I'm not doing damage to the tube by these tests - I can take a better longer video tonight and post.
 
horizontal yoke wires are red and blue
vertical probably brown and white on your yoke

this sounds like an issue in the vertical circuit but your next video will prove it
 
New Video - this was filmed in 4k, but it will take some time to process so low quality until that happens. Headphones at least for me sound better to hear the sound its making.

 
Last edited:
OK so big update *doh* had someone say "have you checked the brightness is turned up on the flyback?"

....

so here we are :) however it seems I have some dark edges... not sure whats up here

yWI4426.jpg
 
Use a paper towel tube over your ear and the transistor to isolate the sound, see if the ringing sound is coming from the transistor I uploaded a picture of.

Or if you can isolate the sound and find it's another transistor, let us know which.
 
Use a paper towel tube over your ear and the transistor to isolate the sound, see if the ringing sound is coming from the transistor I uploaded a picture of.

Or if you can isolate the sound and find it's another transistor, let us know which.
Well, whats interesting is once I turned up the brightness - any "worrying" hissing or whatnot from the first video has gone away. Now i just seem to have a really bright center with darker sides etc. Is the sound you are mentioning related potentially to darker sides? TBH im not sure what is considered normal at this stage.
 
If the ringing just went away, I have no idea...
 
Thanks for you help! Ill grab something to plug into it and see how it looks from there. Question - is it normal behavior for the tube/chasis to kick to off if I turn the brightness all the way up on the flyback?
 
Gotcha, yeah that's correct - the picture above where I got the picture has no PCB/anything attached to it - just powered on. Everything in the chain is first time - first time powering on the chassis after recap, power supply after recap :) and the tube after seeing in once where it had issues almost a year ago. So I have no baseline or experience for whats working right or not.
 
First thing I would suggest is dialing down the screen pot on the tube until it’s black. It looks like you have it cranked all the way up.

Secondly I would test and calibrate the monitor using a test pattern from a PCB and following the emphatic or AO guide.
 
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