Samsung 510N/710N - are these 15khz compatible?

[appiah4]

My online research seems to indicate they work fine with an Amiga (found one video of [ Show youtube player ] and I believe that's also 15Khz), but I was wondering if anyone uses one of these monitors and can vouch for internet hearsay.. I'm on the verge of buying one second hand to have a 4:3 flatscreen around to use one day (I can't rely on my 1084S forever ).

[Amiga1992]

I don't think so, the GBS 8200 I thought was an upscaler or something, so it probably is outputting 31Khz to that VGA monitor.

That does not mean this monitor doesn't sync to 15Khz, but with the GBS in between you cannot tell.

From the tech page of the GBS:
Supports VGA output 640*480,800*600,1024*768,1360*768
CGA/EGA signal auto scan(15K,24K,31K)
YUV(YPbPr) signal auto scan(480i,576i,720i,1080i,480p,576p,720p,1080p)

I don't really understand. Seems to suggest output at CGA/EGA could be 15Khz, but nothing clear is said about VGA.
Someone with a GBS will probably be able to shed some light, and someone with this monitor could confirm or deny if it works at 15Khz.

this dude at Amibay is maintaining a list of compatible monitors, you should take a look and make a buiying decision based off it:
http://www.amibay.com/showthread.php...al-23pin-conns

[appiah4]

Originally Posted by Akira

I don't think so, the GBS 8200 I thought was an upscaler or something, so it probably is outputting 31Khz to that VGA monitor.

That does not mean this monitor doesn't sync to 15Khz, but with the GBS in between you cannot tell.

From the tech page of the GBS:
Supports VGA output 640*480,800*600,1024*768,1360*768
CGA/EGA signal auto scan(15K,24K,31K)
YUV(YPbPr) signal auto scan(480i,576i,720i,1080i,480p,576p,720p,1080p)

I don't really understand. Seems to suggest output at CGA/EGA could be 15Khz, but nothing clear is said about VGA.
Someone with a GBS will probably be able to shed some light, and someone with this monitor could confirm or deny if it works at 15Khz.

this dude at Amibay is maintaining a list of compatible monitors, you should take a look and make a buiying decision based off it:
http://www.amibay.com/showthread.php...al-23pin-conns

Interesting. The evidence I have to say they are 15Khz capable are:

They are listed as 15KHz capable here: http://www.retropix.com.br/lista-de-...aceitam-15khz/
They are listed as 15KHz capable here: http://15khz.wikidot.com/
They display 240p and 480i here (though 15KHz is unconfirmed in the video?): [ Show youtube player ]
This site seems to confirm it for 510N: https://translate.google.com/transla...-text=&act=url
This site also confirms 15KHz for Apple II but similar to AMX says a mod for CSync is necessary: http://www.apple2faq.com/knowledgeba...ible-monitors/
As does this site and goes on to explain this has to do with MSX outputting CSync instead of HSync and VSync: https://translate.googleusercontent....WW8R4ydA4D5rpQ

Since the Amiga can output HSync and VSync seperate from CSync and since the DB23-DB15 uses HSync and VSync I don't think the GBS will be necessery at all for the Amiga, I think it's used in the video for seperating CSync into HSync and VSync. So I don't know. Maybe I should just buy one for dirt cheap and test, but I don't have the DB23-DB15 converter, I'll order it from amigakit I guess.. after all we do what we must, because we can.

[RedskullDC]

Hi Appiah4, et al.

I can confirm the 710N will sync down to 15kHz.

Use it here on my 600 through the Silver commodore 23pin->VGA adapter.

Cheers,
Red

[appiah4]

Originally Posted by RedskullDC

Hi Appiah4, et al.

I can confirm the 710N will sync down to 15kHz.

Use it here on my 600 through the Silver commodore 23pin->VGA adapter.

Cheers,
Red

Thank you

[idrougge]

I bought a 710N and it didn't work.

[appiah4]

Originally Posted by idrougge

I bought a 710N and it didn't work.

It seems that some serviced 710N models actually have 740N control cards in them; did you by chance check the innards of the monitor?

[demolition]

Also be aware that passive RGB-VGA adapters (like this one) may not work with all monitors. The silver Commodore ones have buffers for the sync signals.

[appiah4]

Originally Posted by demolition

Also be aware that passive RGB-VGA adapters (like this one) may not work with all monitors. The silver Commodore ones have buffers for the sync signals.

Getting one of the original VGA adapters and a second hand cheap LCD together cost half of what a cheapo scan doubler would so maybe it's not really such a wise move on my part eh.. Thanks

Dell U24 models seem to have 15khz support. I wonder if my P24 would support 15khz as well.. Manual says no, but the U24 manual also says no. I would try if I had the adapter, but alas..

[demolition]

Well, for the electronics-savvy, it is not hard to build an adapter cable yourself with the buffers. I took a normal VGA cable, put a DB25 connector on one end (cut to DB23 size) and a 7404 hex inverter chip inside the shell to function as a buffer for the sync signals. Works great. Since I used two inverters for each sync signal as buffers it even allows me to switch the polarity of both H and V sync in case some monitors might prefer one way or another.

[appiah4]

Originally Posted by demolition

Well, for the electronics-savvy, it is not hard to build an adapter cable yourself with the buffers. I took a normal VGA cable, put a DB25 connector on one end (cut to DB23 size) and a 7404 hex inverter chip inside the shell to function as a buffer for the sync signals. Works great. Since I used two inverters for each sync signal as buffers it even allows me to switch the polarity of both H and V sync in case some monitors might prefer one way or another.

Do you by chance have a photo of the inside of the DB25 that you put the chip in? I have every component necessary for this hackjob aside from a soldering iron, I could go ahead and try it if I had an example to go by I think..

EDIT: I'm getting a strage Deja Vu here, have we actually had this same conversation before..

[demolition]

Don't have a photo already, however it is probably hard to see what's going on in a photo. It is a pretty simple circuit however. You need the inverter IC with a 100nF decoupling cap across the supply pins, connect Hsync from Amiga RGB to one inverter input, VSync to another input. Connect the outputs of these two inverters to the inputs of two other inverters and connect the outputs of those to the VGA sync pins. The inputs of any remaining inverters should be connected to Gnd.

If you want to control the polarity you can have a switch that selects between taking the output from after the first or the 2nd inverter.

You could also use two NAND gates and control the polarity by applying either Gnd or Vcc to the other input of each gate.

[appiah4]

I could try this on a breadboard I think..

I also came across this: http://amigabr.blogspot.com.tr/2012/...-para-vga.html

Does this look correct? The diagram seems to be missing a connection to pin 8 on the inverter (it is there on the board) and he used a 74HC14 instead of a 7404 (and the originals seem to have a 74HCT08) but I guess they should be interchangable in this case?

[demolition]

Looks like it should work. The schematic is missing the connection to pin 8 yes, but the dot is there for the connection.

Using 7414 instead of 7404 is perhaps even better since it will be more noise-immune than a plain inverter.

[appiah4]

Originally Posted by demolition

Looks like it should work. The schematic is missing the connection to pin 8 yes, but the dot is there for the connection.

Using 7414 instead of 7404 is perhaps even better since it will be more noise-immune than a plain inverter.

Funny thing is, his diagram shows 74HCT14 and he used a 74HC14. They have quite different voltage highs, apparently HCT being MUCH higher (4.5V vs 2.0V). Commodore's chip HCT08 has a high of 1.6V so the chip he actually used is a lot closer. Would the HCT14 even have worked?

Anyway, I ordered the parts, including an HCT08 (like commodore's) and an HC14 (like this guy's - it's half the price so I'm thinking he just cheaped out :P) and will check which performs better

[idrougge]

Originally Posted by appiah4

It seems that some serviced 710N models actually have 740N control cards in them; did you by chance check the innards of the monitor?

No, I threw it in the trash.

[idrougge]

Originally Posted by appiah4

Getting one of the original VGA adapters and a second hand cheap LCD together cost half of what a cheapo scan doubler would so maybe it's not really such a wise move on my part eh.. Thanks

You don't have to get an original. People on Amibay sell new ones, and I make them on order as well.

[demolition]

I found some documents from Commodore which contains the schematics for different types of RGB to VGA adapters (also a genlock compatible one) as well as an explanation about why they are designed the way they are and I thought this could be interesting for someone..

[damiraga]

Based on this document, does this mean the -03 version of the sync dongle only works with the NTSC Amigas?

Originally Posted by demolition

I found some documents from Commodore which contains the schematics for different types of RGB to VGA adapters (also a genlock compatible one) as well as an explanation about why they are designed the way they are and I thought this could be interesting for someone..

[demolition]

Originally Posted by damiraga

Based on this document, does this mean the -03 version of the sync dongle only works with the NTSC Amigas?

I don't see why it should be NTSC only?