Hitachi 27" 27MM20B Dual-Scan CRT TV??

[Josh128]

Freaking nightmare. Truck is here, early, and it looks like a damned tropical storm outside, lightning flashing everywhere. Im waiting for people to clear out and weather to clear out so I can start unloading. Hasnt rained all week, been hot and humid as shit, of course the weather would wait until now to go south.

[mikejmoffitt]

The schematic has some hand-added parts that imply a second OSD RGB input is present, so it may be as simple as using that and leaving the OSD intact.

In other news, the tube used is a Hitachi A68KSA30X. I think this is the same one used in the American MS9-29SU, so I'm curious how this'll end up (in my experience it's more coarse than even a standard MS9-29 tube).

[nem]

Hope everything went well, Josh128.

In other news, the tube used is a Hitachi A68KSA30X. I think this is the same one used in the American MS9-29SU

Not just American, but European too. My UK built Virtua Fighter 3 had a KSA30X paired to a 29SU. I thought the image quality was excellent on it.

[Josh128]

Guys, I must be on the autism spectrum to have done this or something. Sincerely. Took me six hours to get all this stuff unloaded and moved. I was so drenched in sweat and dirt, it was ridiculous. 4x 16' trailer loads, filled a storage unit with ~40 or so of them, brought 12 home. All by myself. Never again. This was over the top. My body hurts today.

Havent tried anything yet, got home at 9PM last night. I did notice that the newest Hitachi I saw was made in 1999 and has "Ultravision Digital" stamped on the top while others have a blue "MMV" logo, made in 1998. They appear identical other than that. So these may well have been the precursor to the huge 36" Ultravision Digital HD CRT I used to own. The majority of them are in excellent shape, some have some cracks and scratches in the plastic, and about 5 or 6, unfortunately, were shipped face to face and thus have some wear/scratch marks on the glass that likely is not repairable. I saw this in the original photo and should have asked for some kind of padding to be slipped in there. 800 miles of vibration with touching glass is not good. That irks me so bad, but it really is just a few.

Most are Hitachi MMs, 4 or so are some Zenith models, and at least 1 is labeled Ultravision Digital. The Hitachis have a sleek, no nonsense industrial look to them, the Zeniths look more "consumerish", but they ALL have VGA ports on them. I also got a pallet load of 4 head VCRs and DVD players, I dont have any details on those yet, I didnt even unwrap that pallet.

Mike, I hear you about the tube. I wouldnt go so far as to say thats a negative thing yet though, before testing them. I say this because when I examined the phosphor stripes on the powered down sets, the courseness of them look in my estimation to be very similar to the Wei-ya /Makvision M-3129. And I dont know if its just because they were brand new or what, but side compression quirks aside, the M-3129s Ive tried produced a stunningly beautiful picture at all three scan rates, despite what looks to be a course dot pitch. In fact, I'd say they produced the most pleasing Dreamcast VGA picture Ive ever seen. If these things are anywhere near similar to that, its going to be a treat. I pray that they are, because I spent a LOT of money to get them shipped here. A lot. A lot of things are going to have to work out in my favor just to break even, but if the picture is no good from the get go, thats going to be impossible.

[jd213]

I appreciate you doing this, those look awesome. I'm not sure if I will be able to purchase one anytime soon, would definitely like to have one at my relatives' place in PA to use while I'm there, but I don't think I should order one just to have them put it in the basement for me until the next time I visit...

[fernan1234]

Really impressive that you took care of all that by yourself, congrats Josh. These sound like really sweet CRTs.

[nem]

and about 5 or 6, unfortunately, were shipped face to face and thus have some wear/scratch marks on the glass that likely is not repairable.

Scratches can be buffed out.

Very cool. If I was local I would grab a few sets.

Nice work!

[maxtherabbit]

I probably won't be back in MS/LA again until the winter but I'll get one then

[Josh128]

Word man, Im sure I'll still have plenty by that time. Ive got a lot of testing, cleaning, and modding to do. Hope to fire one or two up this afternoon and see whats up.

[donluca]

What a fucking legend, huge props man.

All by yourself? You're crazy, always have a friend by your side helping out!

When I got my Astro City 3 of my friends came instantly to my house to help me and get it from the street in my apartment (I live on the fourth floor and the elevator wasn't big enough).

If I were near you I'd definitely drop in and get one, hope those find good homes!

[bigbadboaz]

Nice, looking forward to first impressions. I hope you move just ONE inside to do all your initial testing on.

[Josh128]

Got a chance to spend a little time this afternoon, not a lot of time to post pics and stuff but learned the following:

1.) This is definitely a dual sync arcade-style monitor! Its beautiful. Tried a GC via a GBS-Control VGA out. The dot pitch in 31kHz mode looks very similar to the Wei-Ya M-3129-- course, but smooth if that makes sense.

2.) When you select "PC" input, you hear a "click" and you can instantly tell from the different look of the text that tells you to "connect a 640x480 source" that its in 31KHz mode.

3.) There is no processing/ no upscaling/ no downscaling/ no lag in either video, s-video, or PC modes.

4.) Tried 15kHz downscale with Gamecube via GBS-C VGA. You get an unsynced/rolling picture, confirming there will indeed be a need to RGB mod the set to get native 15KHz RGB.

5.) You get different menus in 15kHz and 31kHz modes. You get screen position, size, pincushion, contrast, and brightness in 31KHz mode, you get Sony-esque TV picture controls in 15kHz mode.

6.)The service menu is ULTRA easy to access. Simply hold the menu button on the TV down as you press the power button to power on. However, you need the remote to navigate and make changes.

7.)The service menu contains separate control entries for 15kHz "TV" mode and 31kHz "PC" mode. Service mode allows additional stretching than what you can do with the standard menu stretch options.

8.)Service menu has decent geometry controls, but is lacking a rotation control.

9.)I powered on 3 of the sets, every one powered on and at least in the menu text present, all appeared to be well converged and focused!

[Josh128]

Played around some more tonight with one of the monitors. Beautiful, spectacular picture guys. This particular set appears to have minimal use. Zero burn in, zero issues other than your normal CRT stuff. Great color, great blacks. It has that exact "Model 3" 25kHz monitor look IMO. I love it. What a crazy find. Crazier when you consider if I had been local (these came from a Florida school board), I would have gotten them FREE. Incredible.

Found an actual physical manual amongst some of the pallets of equipment. Seems this model shares the Hitachi "Ultrablack" tube tech that the big 36" curved tube HD CRT used. TVL is listed at 600 and dot pitch is listed at .81mm which is just slightly more than the Wei-ya M-3129. This makes sense because the image it produces is EXTREMELY similar, albeit with better geometry and convergence (likely due to the curved tube).



15kHz Genesis via GBS-C 480p

https://imgur.com/gallery/CXol5dD



31kHz Gamecube via GBS-C 480p

https://imgur.com/a/APMPcNY

[strayan]

Wow, the geometry on that thing is phenomenal.

[Josh128]

Wow, the geometry on that thing is phenomenal.

Its not perfect, but its definitely better than any of my Trinitron Wegas. Close but not quite as good as the WG K7000 in my Mace cab, which may have the best geo I've ever seen in a CRT. Curved tubes just have better geometry and convergence in general than flat tubes I guess. The convergence is also very, very good. Much better than my Trins or either of the Wei-Ya M-3129s Ive messed with.

[fernan1234]

Lovely slot mask.

[kitty666cats]

Very similar to the Sampo / NetTV! Which is a very good thing, heh

[Josh128]

Got to test some pure 15kHz mode via NESRGB S-Video output. Also, stitched the TS lag tests to post here.




15kHz S-Video images

https://imgur.com/gallery/IYOnxuH

[tongshadow]

Beautiful set, what a great find!
Hope to see pictures of its insides and of the board.

[Josh128]

Will attempt a 15kHz RGBs mod at some point, will get some nice shots then. Until then, if anyone is interested in one of these, DM me please.

[SuperSpongo]

What a nice haul!

Quick tip, if you want to test these for burn-in you might want to pick up a UV flashlight. That way you don't have to power on each set. Although somehow I don't think that they have seen much use lol

Pictures look great

[Josh128]

What a nice haul!

Quick tip, if you want to test these for burn-in you might want to pick up a UV flashlight. That way you don't have to power on each set. Although somehow I don't think that they have seen much use lol

Pictures look great

I bought one last year for finding scorpions on the forest floor, but now I cant find it. Didnt know they could be used to check burn in on a CRT, thats pretty neat.

[Syntax]

And a hair dryer can help blend them in apparently.

[SuperSpongo]

And a hair dryer can help blend them in apparently.

Seriously? I did a tube swap on a 20 inch PVM because it had "NO SYNC" burned it pretty visibly. I still have that tube because I couldn't bring myself to throw it out yet, it's like new apart from the stupid burn-in. But I don't think I'll ever do that again lol

[Josh128]

Guys, just got some shipping quotes. At least from here to San Francisco CA area, ~$265 for a single unit, ~$314 for two units on a pallet. I would imagine 3 units on a pallet would run $350ish. Thats straight pricing from the carrier, Im not adding anything to those prices. Insurance is optional, carrier quoted me +$25 for $300 of coverage.

I'm advertising on Ebay and FB currently. Currently Im asking $175 for a single monitor, $150ea for 2 monitors, and $125 for 3 monitors on a pallet. This is for terminal to terminal freight shipping, which means I have to deliver the pallet to a terminal approximately 1 hour from me (Ville Platte LA to Broussard LA) and the buyer will need to go and pick up the monitor at the freight terminal nearest him. To cover my gas and time for delivery, I will need to charge $30 (regardless of the number of monitors purchased). I think thats fair.

Also, I have about 5 monitors with minor scuffs and dings in the glass at the center of the front of the tube. I am offering those for $75 as a second or third unit/spare to anyone purchasing 1 or 2 cherry units.

Im trying to be very fair with this pricing. These are truly rare, hard to find sets with exceptionally low hours. I paid over $2000 to get these shipped to me and am also paying for monthly storage so Im just trying to recoup my costs + a little bit extra for all the aches and pains, lol. I will test each and every set prior to shipping and provide standard 240p suite convergence and geometry pictures from each individual unit to its buyer prior to collecting any money.

If anyone has any questions or suggestions, please let me know.

[bigbadboaz]

I can't partake of this unfortunately, but it's great of you to make these available to an audience that can truly benefit.

[donluca]

I'll try reaching out to some people and maybe make some Twitter posts to raise awareness.

Hopefully all this goodness finds a home.

[Josh128]

Pics:

Tube: https://i.imgur.com/UacNu9C.jpg

Jungle IC Daughterboard: https://i.imgur.com/HDIIzk3.jpg

Back of Daughterboard: https://i.imgur.com/1uhu3A9.jpg

Circuit Diagram of Daughterboard: https://i.imgur.com/NXMYpfj.jpg

One thing I dont understand is that the TA1268N on my board is a 56 pin IC, but this diagram shows 52 pins only. For some reason, I cant find Mikes nice, neat little OSD mod diagram that I just saw the other day? I dont remember where I saw it? *EDIT - Found it, it was in MarkOZLAD's signature.

[Syntax]

Happy to help with the rgb mod if you get stuck.
These things look cool.

[Josh128]

Syntax, honestly, I do need help, never done one before. Looking at the OSD Mux diagram you and MarkOZLAD created, it shows the factory series resistors between the OSD output and the jungle were left in place while the resistors going to ground have been (or need to be) removed, correct? Also, the blanking signal should be 3 or 5v DC and come from SCART pin 16 right? Where do I connect my sync pin according to the pinout shown? CV IN or TV/PC1?

Whats your opinion on using the diodes vs the calculated resistors? Which gives more reliable results? Im very interested in how you would approach an RGB mod here. I would love to be able to keep OSD/Menu functionality.