My dad has quite advanced dementia, when I visited him today he mentioned wanting to 'look at the white screen/monitor again', it took me a while to understand what he meant. Essentially he wanted to check the white balance and the RGB (he interjected with CMY also) of the TVs they had in the care home. He mentioned taking the chassis off and finding the 'three screws' which are the potentiometers you are demonstrating here. It might have helped I'm a photographer who spends a lot of time in a colour darkroom, as he's extremely hard to understand, but that's where his head's at - looking to tune in to harmony. Needless to say his Oscilloscopes and tools are staying with me. I have one of those screw drivers on my desk (Dad's actually), they're Stanley Precision Screwdrivers or at least the box I have. Other one's for this job were basic molded tube with a copper flat head I think.
I did a pretty deep dive on this and made 2 videos of my own on how to calibrate color and set white balance. The first step is to calibrate brightness, color and tint with a blue screen and smpte color bars. This gives you a baseline. Then you set white balance. There are tutorials online detailing how to objectively set white balance with a probe and the service manual gives instructions on how to do it with an oscilloscope. After consulting a service manual and talking with two technicians I came up with a technique to correct white balance by eye. It's kinda complicated to be describing in a youtube comment section but you basically do what Steve did in this video--pull up a white screen and use a reference monitor. Important things to point out is that you set subbright first followed by the cuts (gcut, bcut) which are done with the brightness and picture turned down. Then you turn the picture and brightness up and adjust the gains (or drives depending on how they are labeled.) Many CRTs only have adjustments for the blue and green guns i.e. gcut, bcut. If you want to adjust the red gun on these crts you adjust the green and blue guns in tandem i.e. In order to turn the red gun down 5 you would turn the gcut UP 5 and the bcut UP 5. Remember, the cut adjustments are done at low picture and brightness levels. There is a bit more to it but that is the jist of it. No amount of white balancing is going to fix the 8 inch monitor in this video. It's probably too far gone. I would recommend doing a rejuve on the green gun, or all the guns...or you could attach the power cord to the back of a boat and use it for an anchor.
Nice Steve. 2 units in one video. Awesome!! Reminds me when the CES shows use multiple units together to make a big screen to show an image of what they were advertising at their booths. That would be cool to see that with all those sets together like that Steve. 8^) Anthony..
Food for thought: if the monitor can display white, then the phosphors of the tube are ok. I would put up SMPTE bars and compare that to the 20L5. Adjust the red and blue first, then the green. It's strange that the "green" screen looks white.... It doesn't sound like a voltage/amp issue so potentiometers won't fix it.
@@RetroTechUSA what was the probie? Did you find out? I have the same problem my colege tutor is a electronic engineering tutor he said need a new tube.
Thanks for another great video. I have a 14M2UMD unit that only displays red. I’ve been trying to troubleshoot it since June but can never get anything to work. However, I have found when I hit underscan I can see the three RGB lines works perfect. In addition component line B and anything composite do not work. I purchased a working input board off eBay thinking it would work but results were the same.
Great video Steve, hey on the smaller monitor are the potentiometers in the front enough to adjust the color if it's not as affected as this one? Or are you mostly likely always going to need to do some internal adjustments on these older monitors?
Hey Steve thanks for the guide, I picked up a second 8044Q and this was definitely helpful, sadly I seem to only be able to get it to have a green tint or amber tint to the image.
These videos are a very handy resource. Thanks a lot. A PVM-20M2MDU that I recently picked up does not display blue, regardless of input* , cable, source, cranking the blue gain in the service menu, or doing a factory reset. Any ideas? Some Googling tells me that the electron gun has probably failed, in which case it's screwed. * Composite and S-video inputs. I don't have a component source to test with (right now), or a BNC cable for the RGB inputs (yet).
What would you do if your grays/blacks were a brown tint, specifically the Black Level 7.5 IRE is brown while the Black Level 0 IRE looks black? Black and white TV shows look brown, but some cartoons with blacks drawn and some video games have blacks that display correctly.
In my consumer Trinitron TV there are red drive and red cut off controls in the service menu, but I notice that older ones only offer blue and green controls. Any idea why this is? This video reminded me of it because the physical controls on the board only control blue and green until you did the screen matrix one. And is it better to balance color in the middle of the range (like 0 through 63)? I notice average data is low (like 21,14,14 for RGB drive) but the factory settings are higher at about 31/21/21).
I have a 8041Q, and all of my greys are kind of brown. No adjustment of the front pots makes any difference, and when I go to try to turn the internal ones on the B board they look a little like they got burned? And turning them doesn't seem to make any changes for red, and green, but blue does. (Red and green are the ones that show some discoloration on the plastic bit. When I first powered it up the entire screen with no image had a kind of greenish hue, but turning down the screen adjustment on the flyback made this go away. Any ideas on what to look for? Also do you know what I can replace those pots with on the B board? I am good at soldering but do not know what to replace them with :( The pots are: RV115, 122, 118, 120, 121, 205, 118, 119. Lastly what pot would I adjust for the top linearity? The top circles on the linearity screen are oval, but the bottom ones are fine.
The Green colors show up fine on my screen. And the Green dial and the one called RV121 when I turn them will sometimes show a tiny baby spark under the plastic trim knob part, and then the screen goes black for a second, and then comes back to normal. But turning the knobs does nothing. :( I think they need to be replaced but cannot find the parts to do so :(
Any info on how to handle flashing red/green tint issues? I have a 8044q that constantly cycles between normal color and full red bias, sometimes green. Like the pots are all the way on/off
Just a quick question, from what I understand if I have RGB cables from a retro console via Scart, etc. the colors cannot be adjusted (still talking about to 20L5) correct? I ask because I wanted to see if I could have a little more saturation but apparently, that's advised against anyway on top of not actually being able to adjust the gain/phase. Let me know your thoughts if you have time - thanks
Hey there, I have a BVM-D14H5U, and the colours are all over the place. The picture is clear, but nothing in the image is the colour that it's supposed to be. Would the process for calibrating for this model be any different from the video?
im just getting in to PVMs i just got a Sony PVM-14M4U off eBay it was being sold as is cuss it had a green tint to it and i was thinking i could just calibrate it and all would good well that did not fix it i have been trying to get it to look good and i just can't get the color to look right even with the green all the way down it still looks to green and all so blue seems a bit week so im not sure if its caps or the tube cussing this.
I picked up a PVM and the it has colored areas - i.e. a region where everything is biased to red. Would that possibly be a degauss issue or something likely worse? thanks
Hi Steve, I hope all is well with you. I hope you can advise me on how to get BVM parts. I have a BVM A20 F1M. One of the rubber knobs is split(broken) during transport. Could you advise when can I get a new one? Please advise
Hi bud, Semi related question. Have you ever factory reset a monitor? I've seen conflicting reports that the reset sends it back to completely default settings, and others than it just sends it back to it's post calibration state. I've reset a monitor that was completely messed up geometry wise, and it helped a lot, but I'm concerned all the colour settings would be off (although they look okay to me). I've compared it to the service manual and the reset settings are different from the listed "standard" settings in the manual, which makes me thing the monitor actually resets to however it was calibrated and then saved in the ROM. Would you be able to shed any light on this?
depends on model... on 20m2/14m2/20m4/14m4 for example if you activate the 'factory reset' flag at the end of the service menu by setting it to '1' and writing, you'll write the current setting as factory setting if you haven't done that yet by accident, you have to hold the write HV delay button in on the service manual until 'factory reset' appears on the screen and then press HV delay one more time or degauss (I forget which) to get it to go back to the last settings that were set as 'factory reset' unfortunately if you've fucked up (and it seems someone has) like I have, you have to just enter them all in manually
when could you do an advanced guide on color calibrating the 20L5? and is there any place we could reach out to you besides here? it would be great if you had a twitter and we could tweet specific questions to you
I have a 27” Trinitron with a flat screen that doesn’t get to a pure black like it should and has a glow around bright text or anything bright on a black or dark backdrop, and if the bright image moves to a different part of the dark backdrop there’s a trail behind it that’s comparable to motion blur of an original gameboy except it isn’t motion blur, and there’s a dead zone on the left edge of the screen that light gun games can’t pick up. I’ve had these exact issues with every CRT I’ve owned. Is it my outlet causing it, and if so how can this be fixed?
@@RetroTechUSA The strange thing is that I had someone repair it at their house who knows what they’re doing and they didn’t have that problem over there. Also I got an adaptor for HD Retrovision component cables that solved dead zone issues with light gun games
It's weird that there is a dead zone. But the screen not getting black could simply be the brightness knob set to high. You may be able to adjust in the service menu but usually you have to take the cover off the TV to access the brightness knob. As far as a 'ghosting' trail goes, that seems to be normal on black backgrounds with CRTs in my experience.