CRT Fetish Thread

ChuChu Flamingo

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It is well known these kv-27fs100 need the yoke adjusted to fix bottom and top bowing, usually upwards. Pretty common that these sag and get loose as almost all of them have this problem. some have it real bad.

If you look on reddit you can see people who have fixed it.

MKL I tried that white balance adjustment for the jvc d series 201 according to that service manual. It doesn't really work for that model. I still get color bleed on red highs even if I turn down r gain to -25.



1.)Another phenomenon I hate seeing is some tvs i've picked up has what I call the jitters. At 240p it has this weird ~ interference and isn't rock steady no matter the source. Depending on how bad it is unnoticeable to real bad. Generic answer I've read is deflection recap.


2.)MKL what causes this issue below? I've seen people have success recapping the deflection area like Dochartaigh mentioned. Contrast makes it worse but I've seen ones where it doesn't even matter.

qVTbKFY.jpg
 
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MKL

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2.)MKL what causes this issue below? I've seen people have success recapping the deflection area like Dochartaigh mentioned. Contrast makes it worse but I've seen ones where it doesn't even matter.

qVTbKFY.jpg

That issue is briefly mentioned here (column 2, lines 1-11):

https://patentimages.storage.googleapis.com/4c/2d/55/5ea1aaec55200e/US4935675.pdf

The document is reviewing an obsolete design that was used in TVs older than 1980 (the only arcade monitor I know of with such a circuit is the Hantarex MTC90) but the point remains that an unstable current in the horizontal yoke is what causes this issue. In a more modern horizontal output design it can be caused primarily by two things: 1) an incorrect or unstable b+. Typically there are two decoupling caps for this voltage, one after the rectifying diode near the PSU output and the other close to the primary side of the flyback transformer. If these electrolytic caps go bad they will affect the b+ a great deal. But the B+ must also be set at the correct level so it needs to be measured and adjusted if necessary. Further issues in the PSU need to be tackled if the b+ is still not good. 2) The retrace (or resonant) and S-shaping capacitors where the yoke current is stored during the blanking and scanning periods. It makes much more sense to replace these than lots of electrolytics in totally unrelated areas even if they test good out of circuit as you don't know how they will work with peak voltages of 800-1200V after decades of use. These are the 3-4 big blue or red polypropylene caps easy to spot near the flyback and the HOT.
 

Timorous Scott

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I have a pvm 2950 qm and I could not get it to sync without a sync strike. I ended up buying the strike and a vga to 5bnc cable to use with it. I remember having to play via component before said leads arrived. Good but nowhere near as good as the Rgb goodness it deserves

I know this is an old post but I know people here have the 2950. Do you need the sync strike for the 2950Q as well? What did people here end up buying?
 

Timorous Scott

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I know this is an old post but I know people here have the 2950. Do you need the sync strike for the 2950Q as well? What did people here end up buying?

replying to myself in case someone in the future needs it, didn't need a sync strike for a sega mega drive at least
 

ChuChu Flamingo

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Replaced all the Electrolytic capacitors on a Commodore 1702 a few days ago.I think in total it was around 37 capacitors. Only pulled one tiny pad corner off (1/4) on one leg cause my desolder gun got stuck. Pulled out my multimeter and checked continuity to the traces/pins of the ic to make sure everything was connected and it was luckily.

Only capacitors I didn't replace were C905 on the power board (which would require removing the power board from the metal cage) and C536 on the neckboard (has glue on it with a factory resistor). I'll replace them later. Nothing much was wrong with this monitor before cap kit but decided to do it since it is 36 years old.

bLSCgcY.jpg

dEqcrm8.jpg


What do the neckboard capacitors do anyhow? Just curious what symptoms high esr/out of spec capacitors do on these neckboards.

I've read online but can't confirm first hand that replacing them on other crts have fixed color problems (like in Nanao MS9 colors being dull, pretty funny Kernow thread on arcadeotaku about it) or focus.

On a side note I want to destroy whoever thought it was a good idea to bend the solder legs all the way down and solder it. It makes removal so damn annoying.
 
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NEgO MANIAC

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Anyone familiar with Hitachi CT-2160 PVM monitors? I googled the model, but nothing. Maybe these where licensed by Sony? I came across a few, but the sound on them are going in and out. I'm guessing a cap kit?. Also these did not come with the individual RGB BNC connectors. I'd like to know if I can add it.
 

Pinball

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I'm now the proud owner of a Sony BVM-20F1E - my grail CRT monitor. This supplements a Sony PVM-14L2MD which is atop an Olympus medical endoscopy trolley (minus the endoscope!). Nothing like wheeling around some emergency classic gaming :-)

They really do display a superb picture. I got some CSYNC RGB cables from retrogamingcables.co.uk to do them justice.
 

Neodogg

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Found this little B&W 9" monitor hidden at work from the old CCT system...has a bit of burn in but still works...

3rX2GbX.jpg
 

Neo Alec

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I finished RGB modding my Toshiba 32A33 and I made a video. Special thanks to Bratwurst from the forum for all the help!

 

Cousin_Itt

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good video Alec. Pretty straight forward, cited your sources, and you didn't sound like a pompous know it all.
 

massimiliano

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Great video, thanks for sharing...and yes, your voice is relaxing and very divulgative.

One thing, I may be wrong, you say often component referred to the TV native input, but I guess you mean composite?

Also, I also have a moved to the left picture (always had with all TVs in Europe) woudl you mind sharing your thoughts about fixing it, far from using the service menu? (my 10" TV her ein the US has not such thing..I believe...it's a Sony, the usual codes do not work)
 
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Neo Alec

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Great video, thanks for sharing...and yes, your voice is relaxing and very divulgative.

One thing, I may be wrong, you say often component referred to the TV native input, but I guess you mean composite?

Also, I also have a moved to the left picture (always had with all TVs in Europe) woudl you mind sharing your thoughts about fixing it, far from using the service menu? (my 10" TV her ein the US has not such thing..I believe...it's a Sony, the usual codes do not work)
Thanks for your compliments. The TV supports composite, S-video and component (YPbPr) without modification.

Bratwurst was planning to try a couple of things to correct the horizontal position when he has time. I was going to let a professional mess with the yoke and start sticking pots on the jungle before I attempt it. Voultar has some good info on the subject here:
https://shmups.system11.org/viewtopic.php?t=56155

You can often drive and manipulate the H-Phase by a pin on the Jungle I/C. Allowing you far more control than what the service menu provides.

Image

When I add RGB to a consumer set, I look for a pin on the Jungle I/C that can totally control the H-Phase, It's typically driven by a low voltage current.

It's better to do it this way, because you can use the 5V rail coming from a console to drive this pin. Take a 10K trim pot (will give enough play) with 5V and output it to the pin, sweep it across until you get it lined up nicely.

Now, when a console is powered, the 5v will dialed in with the 10K trim pot so that the the horizontal position will automatically be calibrated for RGB.

(This is providing that your RGB cables have a 5v output)

You can also use a switch, of course. A 6PDT is enough to switch your OSD and RGB lines, as well as 5v from the TV to control this.


Just look at the datasheet for your Jungle I/C.
 
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massimiliano

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Thanks for your compliments. The TV supports composite, S-video and component (YPbPr) without modification.

Bratwurst was planning to try a couple of things to correct the horizontal position when he has time. I was going to let a professional mess with the yoke and start sticking pots on the jungle before I attempt it. Voultar has some good info on the subject here:
https://shmups.system11.org/viewtopic.php?t=56155

I see, thanks, I get now that the plastic caps of the Component connectors went off. Thanks for sharing the bit about H-phase using the jungle chip...it's indeed a jack of all trades for these kind of mods! I'll check if my TV has it..
 

DanAdamKOF

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Bought a 14L5 recently. Found the seller by chance and he only wanted $100. Works great!
6f0121d56e1c01c2e00b773ec246cbde.jpg
39513142cb97f3fbf15cbb701d4093b4.jpg
2eef58c705092e886baa46f9693d71b7.jpg
 

ChopstickSamurai

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That looks lovely. I’m sure glad I got into PVM’s before they shot up in price. What these go for now is just crazy.
 

Whippy

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I took a random photo of my console TV today in between a woodworking project and auto issues. I will continue to try to keep it from looking like my grandmother owns it.

 

joe8

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Bought a 14L5 recently. Found the seller by chance and he only wanted $100. Works great!
6f0121d56e1c01c2e00b773ec246cbde.jpg
How big is the PVM on the left? Looks like it's either 27", or 29".
100 is good for a 14" (and it's HR & Multiformat).
 

RAZO

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I have that monitor FW-900. Paired with a xrgb2 it's like crack for your eyes.
 
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