EEVblog #1246 - Dumpster TV to Retro RGB Monitor Conversion

[EEVblog]

How to convert a dumpster Sony CRT TV into a retro computer RGB monitor. Going through the design considerations, schematics, datasheets and the "jungle chip" and how to feed in the RGB signal and switch it. Also a look at the the old school CGA video interface on an IBM PCjr and how to convert it to RGB.
Also a look inside a dumpster Samsung CRT TV

[wasyoungonce]

That's it...I'm going to put a dumster out the front of my house....! 

Score!

[johnlsenchak]

Question ,  what   are you doing  with that old  Samsung  CRT  television ?  Maybe do some high voltage  experiments  with  the  horizontal  output  tripler   

I miss the days of "photonicinduction" videos, that guy was a riot  with his high  voltage   equipments

Warning  bad  Language !

[McBryce]

Not sure how common they were in Australia, but in Europe most TVs of that age came with a SCART input which offered composite, S-Video and RGB. No modding required.

McBryce.

[Moshly]

Not sure how common they were in Australia, but in Europe most TVs of that age came with a SCART input which offered composite, S-Video and RGB. No modding required.

McBryce.

SCART is very uncommon in AU, normally only on high end gear.

[Just_Understand_It]

Photonicinduction: a modern Faraday? Maybe not. :-)

[Ben_Ingram]

Great video. Just in case anyone has to chose between rescuing a Sony or Samsung, go for the Sony.

I wrote to Samsung UK asking to purchase a service manual this the response from them:

" we do not provide the schematic diagram or service manual of our TVs"

That is for my own not so old LCD TV model UE40D552

In future I'm checking manual availability before spending cash on any new products.

Ben

[SeanB]

Reason they used an external OSD driver is because of no input sync. The MCU can use the horizontal and vertical free running oscillators of the jungle chip internally, with a hardware counter counting lines since a vertical sync pulse, to get a set of registers that can be programmed to have a constant position on the screen, nearly irrespective of any input signal, just using the natural free running of the 2 oscillators. Then use a bit clock generated internally to put out the signal to override the actual jungle chip output, and pull the drive to full brightness as desired to generate the OSD.

This then will be nearly constant in position, and the jungle chip itself does not provide this, as it relies on having a valid vertical and horizontal sync to do the internal OSD, and otherwise will have a lot of jitter. Doing it externally makes it simpler, allowing you to use region specific chipsets, though I will guess that, if you remove that power filter board, there will be a set of traces for the SCART socket there, and probably the components for the socket as well, and this will allow you to select the SCART by simply forcing the SCART select input high with 5V, switching to the SCART instead of the line input. Right position for the SCART socket, and that blanking plate is a separate piece of the moulding, for different models.

[@rt]

I hope you come by a real Trinitron some day Dave. I wouldn’t miss that video for the world.
It doesn’t matter if you turn it on or take it apart, it would be hilarity both ways.

There’s a big problem moving them. I’ve got no faith that one sent interstate would arrive undamaged.

I appreciate there’s educational content in the video and all, and the TVs are easy to get for other people (viewers), but Trinitron aficionados please lol.

[cheater]

If you're willing to make your own raster scan driver, what is actually limiting a CRT TV from supporting increasingly higher resolutions?
I have a large, high quality Sony CRT TV (32", 16:9, one of the last generations) and I wonder what resolution the tube could theoretically support. A raster scanner isn't an insurmountable amount of work.

Thanks.

[jonovid]

if the old  Samsung  CRT  television is not needed
give it a RGB monitor conversion too.  I am sure that retro video gaming has the same popularity in Sydney.
so you can sell any moded CRT  television at a retro video game monitor.

if this is a help- look for the M52797SP  this video switching chip or similar type video bus control chip is found in many crt television pcb's
it controls and or switchs the R,G,B, between TV tuner & auxiliary video inputs.
M52797SP is a 3x  4 position 3 pole video switching in a chip. control is by two pins  digital logic table or  I2C bus control
as this is a discontinued analog video ic from the 1990s , so the is datasheet re-posted here-
https://drive.google.com/file/d/1f7aa9mEgG48Gvd6UtEPcJgGVq4EpUwis/view?usp=sharing
this may just help in mapping the  R,G,B, between TV tuner & auxiliary video inputs.

[salfter]

It could be that the reason you're finding this TV so much different than the other similar models inside is that that Sony TV/VCR combo you've stumbled across is a multi-system device that supports both PAL and NTSC video.  The electronics will no doubt be different on account of needing to handle different variants of NTSC and PAL (and sometimes even SECAM).  Note that the model includes an extra letter (KV-14VM5G) that isn't in the list that shows up at 12:04 (all KV-14V5* or KV-14V6*).

I think my parents still have some multi-system gear kicking around from the last time Dad was stationed in Germany in the late '90s (and maybe even from when we were all over there in the '80s), so I did a double-take when I saw some multi-system equipment pop up in this video.  At least here in the US, you pretty much never saw these things sold in stores; ours all came from the BX or other on-base A/V shop on American military bases overseas.  They were especially useful in England, where AFN wasn't available and the four channels that made up British TV (broadcast in PAL) were all that was available.  Near American bases in Germany, you could pick up AFN, which broadcast a low-power NTSC signal that didn't carry more than a handful of miles.

How much use there would've been for a multi-system TV/VCR combo in Australia, I couldn't say.  Maybe the business that owned it used to get tapes sent from the US, Japan, or some other country that used NTSC back in the day.

[mubd1234]

Not sure how common they were in Australia, but in Europe most TVs of that age came with a SCART input which offered composite, S-Video and RGB. No modding required.

McBryce.

SCART is very uncommon in AU, normally only on high end gear.

I think most Sharp TVs came with SCART connectors. I remember my family's TV from my childhood only had one SCART connector, which I thought was inconvenient because we needed to use an RCA to SCART adaptor for my Xbox. Our analogue Foxtel box also had it, it was just a simple SCART to SCART connector for that one.

And funnily enough (a coincidence?) I actually found this almost identical Trinitron to the one Dave found, on a nature strip in West Ryde the other day.



I got it home and realised that it had a British plug fitted to it. No SCART connectors, just the RF on the back and the RCA mono input on the front. The only thing wrong with it is the tape eject mechanism appears to have failed (the bit where it spits the tape out). If I yank the power cord out as the tape reaches the slot, I can fish it out with my fingers.

[EEVblog]

I hope you come by a real Trinitron some day Dave. I wouldn’t miss that video for the world.

And what exactly is a "real" Trinitron?
Does this not use a trinitron tube?

[RobertPS]

I wrote to Samsung UK asking to purchase a service manual this the response from them:

" we do not provide the schematic diagram or service manual of our TVs"

That is for my own not so old LCD TV model UE40D552

In future I'm checking manual availability before spending cash on any new products.

Ben

Perhaps this is the one you need:  https://elektrotanya.com/samsung_chassis_u66a_ue32d55_ue37d55_ue40d55_ue46d55_ue32d57_rs_ue37d57_ue40d57_ue46d57_chassis_u57a_ue32d50_ue37d50_ue40d50_ue46d50_chassis_u57b_ue19d40_22d50_27d50.pdf/download.html

[Clear as mud]

And what exactly is a "real" Trinitron?

I think he is talking about one of the big ones.  I am not very familiar with Sony's naming schemes, but I know that we once had a 27-inch Sony Trinitron TV with a wood cabinet and stereo speakers.  That thing was heavy!

So, what does "Trinitron" really mean?  My wife says it's a technology thing, not a size thing.

[paul_g_787]

Unfortunately though the RGB on SCART only accepts interlace signals. In the UK 576i at 50Hz (although some TVs support 480i)

If there were a device to convert 576p to 576i then one could connect a VGA input from a PC to an old CRT. I would love to know how to do this so I can put a Kodi box in the bedroom

[German_EE]

It's nice that we are able to do this sort of stuff on modern TV sets. Some of the old TVs had a live chassis depending on how you connected the power plug, that would have made computer interfacing an interesting challenge.

If you see any sort of interfacing on the back such as SCART, YUV or even audio you're probably OK as all of these will require a ground connection to function.

[paul_g_787]

So, what does "Trinitron" really mean?  My wife says it's a technology thing, not a size thing.

As far as I understand "Trinitron" is Sony's name for their CRTs which have three individual electron guns (red, green and blue) and therefore draw all three colors in a frame simultaneously on the screen.
Whereas other makes of TV TVs had a single electron gun and drew one colour after the other.

[McBryce]

So, what does "Trinitron" really mean?  My wife says it's a technology thing, not a size thing.

As far as I understand "Trinitron" is Sony's name for their CRTs which have three individual electron guns (red, green and blue) and therefore draw all three colors in a frame simultaneously on the screen.
Whereas other makes of TV TVs had a single electron gun and drew one colour after the other.

Actually, all colour CRT's sent the three colours simultaneously and had 3 electron guns. The difference with Trinitron was the fact that the 3 colours were rectangular and next to each other (3 in a row), rather than 3 circular points in a triangle configuration that other CRT's had.

McBryce.