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I had a 20M4U shipped to me, I know it's not the greatest idea but I've had a 20M2MDU shipped to me and it turned out fine so I decided to roll the dice again. It arrived today with no visible damage outside but I turned it on and was greeted by this (that's not the photo, it really is bright blue in addition to the visible raster lines, and also kind of flicks between different shades of blue):

MTTYUL6.jpg


I performed a factory reset and tried degaussing (via the degauss button) which had no change. To my eye internally it seems fine:

KSYLz2c.jpg

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m7WPbYf.jpg

3VVZsmC.jpg

NX1rt76.jpg

w9KLHyN.jpg

3WsrEts.jpg


I was shown pictures of it working correctly before buying so I'm pretty sure this happened in shipping. I've checked that all cable connections are seated correctly. Does anyone know where I should go from here to troubleshoot this?
 
How was it shipped/packed/carrier?

Try to check for cracked solder joints?
 
How was it shipped/packed/carrier?

Try to check for cracked solder joints?
It was shipped via FedEx, double boxed with lots of padding and clearly marked all over the box "fragile" and "glass". I am currently inspecting the boards but everything looks fine so far. I am more wondering what this kind of problem is a symptom of so I know where to focus my attention.
 
The raster lines like that are generally caused by the flyback being turned up too high. you'll want to adjust down the "screen"/"gain" pot on the flyback.

if this was working properly before it was shipped then it's possible you got a cracked/cold solder joint somewhere, potentially around the flyback or part of the B+ circuitry that drives it.

you'll want to pull the boards and inspect for solder joints that look like this:
2010-05-09_174104_Issue_1.jpg

or like this:
2010-02-11_174149_solder_joints.jpg
 
The raster lines like that are generally caused by the flyback being turned up too high. you'll want to adjust down the "screen"/"gain" pot on the flyback.

if this was working properly before it was shipped then it's possible you got a cracked/cold solder joint somewhere, potentially around the flyback or part of the B+ circuitry that drives it.

you'll want to pull the boards and inspect for solder joints that look like this:
2010-05-09_174104_Issue_1.jpg

or like this:
2010-02-11_174149_solder_joints.jpg
Yeah, I have tried the screen pot (knew to check from my experience with arcade monitors) and even near it's lowest setting it stays looking the same way. I am also familiar with cracked solder joints but haven't spotted any yet :(
 
Your honestly lucky it still even turns on, I've personally seen shipping kill a PVM-20M4U and a BVM-20L5.
NEVER SHIP THESE MONITORS (I don't care how well you pack it)!.. That's the only advice I've got for you, sorry its a little too late to save this one. :/
 
Yeah, I have had other CRTs damaged in shipping as well (though not PVMs). I think I am just going to return it.
 
Your honestly lucky it still even turns on
I shipped a D24 FedEx and it arrived suuuuuuuuuuuuuper bent and busted looking. The whole case was beat to hell, even a 2" puncture on one side, but the damn thing still worked! The guy got more than his money back on the insurance claim and got to keep the BVM, so it all worked out sorta.

I agree that UPS/FedEx should definitely be avoided.

Shipping through some white glove freight service should be fine though, even if it cost a bit more at least you know it's being taken care of.
 
I had my BVM shipped from NY up to here in California years ago... but it was double boxed in two boxes like 3x the size of the monitor and foam suspending it in the center.

e:nm but It definitely looks like some kind of screen voltage issue, but at least the OSD looks alright so your tube is fine. I would try to figure out what would cause that adjustment to not work.
 
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The screen voltage adjustment is normally a potentiometer between gnd and the maximum screen voltage. I once had an issue that the gnd connection was broken. Due to that, I also had flyback lines and a way to bright image. The screen voltage is 2 high to measure normally, but you might be able to measure the potentiometer. It can be cracked internally as well. Looks like this monitor has a separate focus control potentiometer on the neckboard. Most of the chassis I have seen have the focus and screen potentiometers in serie with each other.
 
Could be the screen adjustment got bumped on the neck.
Or, that the pin snapped of/shorted in transit.
You need to check this video properly and get a plastic adjustment tool to adjust the screen voltage if it's on the neck board.

in the video, the screen adjustment is not near focus so you really really need a plastic tool that fits in the hole.
There's 10.000-20.000 Kilovolts involved and you do not want to kill yourself really.
 
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