Monitors...

[prismra]

Ok, I'm back with more newbie questions.

I've done some research and from what I could find, you can use a SVGA monitor with an RGB-VGA adapter and set up an A1200 to use a driver that makes it run at 31 khz.  BUT, I also read that some old games and demos (the MAIN reason I want the machine) will assume a 15 khz standard TV/Commodore monitor so I'll be screwed basically since no new monitor uses a 15 khz horizontal frequency.

Soooo, do I need to get a Commodore 1084 off eBay to make this happen?

[motorollin]

prismra wrote:
I've done some research and from what I could find, you can use a SVGA monitor with an RGB-VGA adapter and set up an A1200 to use a driver that makes it run at 31 khz.

No, that's not correct. The output runs at 15KHz because that is how the hardware works. You can't change that with software. If your monitor supports 15KHz then you can display Amiga screenmodes on it, but if it doesn't then you need a scandoubler (hardware) to double the scan rate to 31KHz.

prismra wrote:
BUT, I also read that some old games and demos (the MAIN reason I want the machine) will assume a 15 khz standard TV/Commodore monitor so I'll be screwed basically since no new monitor uses a 15 khz horizontal frequency.

Some multisync monitors sync down to 15KHz so will display the Amiga's screens. If you use a scandoubler then you don't need to worry about this, you can use any VGA monitor.

--
moto

[prismra]

Ahaaa! :idea:

Ok! I think I get it now.  So I can use ANY VGA/SVGA monitor with an RGB-VGA adapter as long as I use the scan doubler to, well, double the horizontal scan rate.

Ok, so I can then use any vga monitor that takes a 30 khz horizontal scanrate.  Sweet!

So where can I get one of these magical scandoublers and can I stick one inside a A1200 (non-tower [is there a term for that?])

[motorollin]

prismra wrote:
Ahaaa! :idea:

Ok! I think I get it now.  So I can use ANY VGA/SVGA monitor with an RGB-VGA adapter as long as I use the scan doubler to, well, double the horizontal scan rate.

Actually, you don't need the RGB->VGA adapter, as ScanDoublers designed for Amigas connect directly to the Amiga RGB port. Alternatively, you can do what I have done and use an Amiga->SCART cable, and one of these.

You only need the RGB->VGA adapter if you are connecting directly to a VGA monitor that supports 15KHz.

Ok, so I can then use any vga monitor that takes a 30 khz horizontal scanrate.  Sweet!

Yup :-)

So where can I get one of these magical scandoublers and can I stick one inside a A1200 (non-tower [is there a term for that?])

You can get internal scandoublers that connect directly to the A1200 motherboard. They come with a blackplate to connect to a tower, but in your desktop A1200 you could just trail the cable out the back. Alternatively, you can get an external one which connects to the RGB port. You can find scandoublers on eBay but they are extremely expensive!

Alternatively, do what I have done with the Amiga->SCART cable and then any consumer SCART->VGA box.

--
moto

[prismra]

Is there a real disadvantage to finding an old commodore amiga monitor?  It seems to be the cheaper alternative!

Like if I decide to use OS 3.9 will I be screwed on higher color depths on the desktop?

[motorollin]

No, of course using an Amiga monitor (or even a TV with a Scart cable) is a real alternative. I just thought you wanted to use a VGA monitor  ;-)

The advantage of course is that VGA monitors are readily available and cheap. Commodore monitors are neither.

Also, if you get a scandoubler and a VGA monitor, then you have the option of using higher resolutions for your Workbench, and you can use the same monitor if you decide to upgrade to a graphics card at a later date.

--
moto

--EDIT
A scandoubler won't let you use any more colours than with the standard Amiga output to a TV. You need a graphics card to get more colours on screen.

[Jose]

"...No, that's not correct. The output runs at 15KHz because that is how the hardware works. "

Hi. No that is actually incorrect, AGA can output 31Khz and even more as long as the drivers tell it to do so, most usable screens with vertical refreshes higher than 15khz are 31Khz though. The problem is that some games/applications (specially older ones and demos)use the AGA hardware directly and make it run at 15Khz so in that case there is no way to force it to run at 31Khz. Actually there are some programs that try to do that and work at times but many/most times they're not successfull. So for what you want a scandoubler might still be the better option. That or a nice bigscreen 100TV ;-)

[lurkist]

Your first statement was pretty close, you can use a RGB-VGA adaptor to use your system on a VGA, using a DblPAL or DblNTSC screenmode, but as you say old games / programs will not usually let you select a Dbl mode and will thus be invisible.
Old Amiga monitors (the Philips 8833II for instance) will show everything but flicker in hi res modes.
Scandoublers - hard to find and expensive, but display everything rock solid.  Aparrently some are better colour-wise than others (see separate threads.)

[prismra]

Ok awesome.  Thanks again, man.

I think I'm going to find a commodore monitor on eBay.  They seem to be fairly cheap.  I have an old VGA monitor but it seems the cables/boxes/scandoublers etc will cost way more than to find an old commodore monitor.

What is a recommended one?  I read the 1084 is  a good one.

[motorollin]

Jose wrote:
AGA can output 31Khz and even more as long as the drivers tell it to do so,

Wow, I didn't know that  :-)

--
moto

[leirbag28]

@motorollin

Yes, AGA and all Amigas can disply 31khz with software and Workbench......just simply Drag the Multiscan Monitor and DblPAL and DblNTSC monitor icons from your Workbench:Storage drawer............and drop it into the Workbench:Devs/DosDRIVERS drawer, reboot.....and select Multiscan Productivity mode (31khz VGA0 or DblNTSV/PAL  (27 - 29khz?  but still VGA)

its that easy.

The best solution?? get the 1942 Commodore monitor.it display VGA and regular RGB...basically all AGA screen modes.

[prismra]

So, uhh, what's the difference between composite and RGB?

The composite is the RCA jack on the back (yellow?)

and the RGB is the DB-style connector?

Is there a large difference in quality?  Does it take a special cord?

[motorollin]

Composite is a single phono connector and is of much lower quality than RGB. The Amiga's RGB connector is a 23 pin D type connector, but inside it is standard RGB. You can buy cables from eBay that will plug in to the Amiga's RGB socket and convert it to Scart so you can connect it to a TV. If you want to conenct it to a Commodore monitor then you need a special cable.

--
moto

[InTheSand]

motorollin wrote:
Alternatively, you can do what I have done and use an Amiga->SCART cable, and one of these.

What's the quality like? Any good? Any visible artifacts or other on-screen junk as a result of the conversion process?

 - Ali

[AmiDude]

@InTheSand wrote:

What's the quality like? Any good? Any visible artifacts or other on-screen junk as a result of the conversion process?

You can read all about it in this thread:

www.amiga.org/forums/showthread.php?t=18582

 :-)