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The ones I got were off aliexpress, I think those other sellers just buy from there and resell at a markup.
got it, it seems the recent batch isn't working correctly unless there's a trick to installing that John at PNL doesn't know.... two bad ones in a row.
 
I ordered a 3 from TB focus, they took many months to ship so I also paid out the ass for two from a guy on ebay.

I think I'm going to invest in a HV probe and measure what type of voltage is coming out of these guys.

EDIT: also worth mentioning the last couple of times I fired this thing up it has had slight issues with focus and a reduced screen size. It takes 2-5 minutes to get to the point where everything ends up looking quite nice though!
 
It appears that the MS-2930, MS-2931, and MS-2933 use the flyback solely for producing HV, focus, and screen voltages. The rest of the chassis appears to feature independent power supplies. With that in mind, shouldn't adapting to other flybacks be easier than with an old-style chassis that uses flyback windings for much more than those purposes?
 
I’m at around 25 kV on both of my monitors that I’ve installed these in now... was around 20 kV on this ms2930 until cranking the hv pot all the way clockwise.

the 2931 was a little under 25 kV but after jacking that up (counter clockwise on the ms2931) I’m about at 26kV
Edit: worth noting that the 2930 image was blurry on startup but I did not get a reading until it was in focus. The initial 20k reading was after the monitor had come into focua

Edit2: two days later the 2930 seems worse off now. Monitor has neck glow but image appears only for a few seconds on start up then expands into the void. If b+ is stable and the HV on the anode is also stable then could it perhaps be a failing HOT?
 
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Can anyone with easy access to a chassis tell me whether either of these are suitable replacements for the HOT in an MS2930?
https://www.ebay.com/itm/Nanao-MS29...067289&hash=item4b74805517:g:ZPIAAOSwEdteTC-p
https://www.arcadeshop.com/i/1337/2sd1880-horizontal-output-transistor.htm

I want to order this part but am in the middle of a move and probably won't have the opportunity to pull my chassis and check for a bit.
Also am having a hard time finding a parts list for this monitor

Edit: I have since "readjusted" the monitor following this guide https://wiki.arcadeotaku.com/w/How_to_Correctly_Set_Up_Monitor_Colours_and_Brightness
It looks very nice after warmup (~15 minutes) and still crappy on startup(out of focus, small picture, slightly too bright). Just gonna live with it for now until I get the time to mess with it a bit more. I am considering a more thorough cleaning of the "goop" I cleaned under the flyback when I did that swap but there is still a fair amount surrounding some other components. The goo never got to the pots though.
 
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Figured out my issues with this chassis finally.

long story short is
I needed to replace the 2sA1624 and 2sc4218 transistors on the neckboard.
Some of these had failed when the monitor initially crapped out and I did not replace them with properly cross referenced parts the first time which I think resulted in the "warming up". As soon I replaced them with some known good parts from a functional chassis everything started acting normal.
 
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