Anyone Good with PVMs?

[madhatter667]

So, despite having a decent TV for gaming, I couldn't pass this up. PVM monitors don't pop up often in my area, let alone free. Of course, free comes with a caveat: It needs repair.

I believe that what I am looking at is partial vertical collapse. Moving the monitor around changed what I saw on screen (or it has a higher tube warm up time than I am used to). I am guessing that this is bad connections on the vertical control board? I also understand that it could be a bad IC for the vertical controls? It isn't complete vertical collapse though. Hoping that the monitor is salvageable, as it is very interesting, and the number of controls provided over the display is rather interesting. Model PVM-1341. Only a 13" but even just testing a SNES game on it, through a clone console (easily on hand to plug in and test). Colors are a little off due to futzing with the controls here and there.

Wondering if there is a way to hook the ST to it. But that is a post repair concern. Here are some pics of what I am looking at. You can see the collapse line near the top of the screen. Blurriness is from my camera.

[Keatah]

If you suspect there are bad connections on the vertical board, then start inspecting there. Mojoatomic seems to know old-school electronics pretty good..

Edited February 19, 2017 by Keatah

[7800fan]

Obvious disclaimer, avoid touching the thick wire that goes to the side of the CRT. Even when it's not plugged in, it will still give you a nasty shock. There are guides on how to safely discharge but I usually use a screwdriver, 1 megaohm resistor, a wire with alligator clip, and have it short from the metal clip under the suction cup to any exposed metal spot. The resistor prevents rapid discharge that could cause spark or damage something.

 

Then re-seat every wires you see. The yoke usually have 4 wires, check that those are securely in place. If it's not connected via plug but soldered in, get a magnifying glass and check for cracked solder. Whatever you do, do not move the yoke itself, you will mess up alignment and it's a royal pain in the ass to get the yoke aligned correctly. (have done it before, replaced burnt out yoke, spent a couple hours tweaking the new yoke while the CRT was powered on and running a video grid pattern*, then had to adjust the converge rings to fine-tune the alignment) Trust me, adjusting yoke is not worth it today unless you got a really nice large PWM display worth keeping.

 

Uncomfortable with this? Maybe you can find a local help?

 

*back in the day, it was an expensive piece of equipment that did square grids, dot grids, cross, box, and color bars to help with alignment. Today a desktop or laptop with images in full screen + cheap VGA to composite converter is all I need.

[madhatter667]

There are a few places locally, and I am currently reaching out to them as a possible solution (if the repair isn't super expensive, I'd pay someone experienced to fix it). I'm a little leery of the high voltages involved, but wouldn't be as afraid once properly discharged... as parts are parts, and they all go in a certain way. Do you have a pic of how you rig the screwdriver? I've seen some videos, and some of those guys seem gutsy. Lol.

Colors are great, vertical hold is really cool (ability to run PAL without converting craziness). While it's only a 13", I could easily see a larger one becoming a main vintage display. Very nice otherwise. I also did a LOT of NES gaming back in the day on a 13" CRT when I was a kid. It was rad to have it set up in my bedroom vs. the SNES in the family room. Lol. It's at least a playable size screen. I will be keeping my eyes out for a larger RGB monitor display, as a buddy has recently told me about a few other models that are also quite good... and I am finding myself thinking like one of "those guys." Lol. I'm pretty happy with my collection/systems. Yes, there are ones that I would add. I see no harm in getting the max out of stuff that I otherwise really enjoy though.

 

I also generally like the opportunity to learn. However, there is a bit of a curve to this one.