Amiga VIDEO - VGA (DSUB) Adapter

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@daleblazer: what is the buffer/inverter mod ?


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The buffer / inverter mod places two inverters between the Vsync and 2 between Hsync, this is required for many of the monitors on the large box Amigas. for some reason my 500 does not need this. You need to get a 74LS04 IC, (cheap on Amazon or anywhere), and a .01uf cap to go between the 5v and ground. what I did was connect it all into this same little adapter that I purchased from Amikit a while back. After that my monitors worked on the 4000, 2000 and 1000. I also read where this buffer protects some your Amiga's video circuits as well, however, I do not have a lot of info on that.

Here is some more info on this:

http://www.epanorama.net/faq/vga2rgb/vgamonitor.html

I need to make one more pretty soon, I can send some pictures of this mod as I do it if you like.



 
Here is my experience. I am using an NEC 1970nx (another very nice 15khz monitor) I have tested it on the Amiga 500, 1000, 2000, and 4000. With a buffered adapter (commodore) it will work on all models of Amiga's. With a straight wired adapter an no inverters installed, it will only work on the Amiga 500. the 1000, 2000, and 4000 all needed the buffer. They will not even boot. Something about the computer thinking it has a genlock installed rather than a monitor. The buffer/inverter mod is very easy and cheap to install and all fits nicely in that little case. I made one this last weekend and now all of my Amigas will work with my NEC.
Same experience here with an old 15" unbranded monitor LCD I have been using; wired adapter doesn't work, buffered adapter works very well (and this monitor also has speakers.) I wish the BenQ had speakers, though.
 
We were talking about buffered/unbuffered at the beginning of the thread also. Some info is also in this thread.
Great is that the BenQ accepts unmodified Amiga signal perfectly (no need for buffered sync), this particular BenQs remind me of the multisync Amiga monitors like Commodore and Microvitec. They simply work with most resolutions and with the ease of just connecting the cable.
 
As an alternative to Amiga Video RBG - VGA Adapter you can also use my completly modified SVGA cable for even more comfortable and most easiest way of connecting Amiga to BenQ BL702A / BL912 monitor. More info here on my other cables and adapters thread.
1amigasvgacable.jpg
 
adapter arrived! good thing is it works perfectly with NEC 19 nx :D !!! i just have one problem, Amiga won't boot if monitor is plugged in (i use gotek adf) did i miss some advise regarding normal boot??? is there a solution for it?
 
Perfect news if your NEC works :) Can you tell the exact model number I will add it to the list or working monitors.
I would need more info about boot issue, because plugged monitor normally shouldnt interfere with the boot proces.
 
Model is LCD NEC multisync 1970nxp . i have several amigas, i just tested it on my a2000 with gotek adf usb adapter. however if adapter is plugged in, amiga won't boot at all and the screen remains in sleep mode. but if i start amiga, wait 10 sec than plug adapter, it works ok. i run the last ninja 2 (pressed auto-adjust on the monitor) and the picture is OK!!! if i find time i'll put some screen shoots tomorrow. also will try on a1200.
 
What if you start amiga with adapter with monitor switched off and later switch monitor on?

no change, it's the same - won't start. i read some time ago that somehow amiga with such adapter expecting a genlock device connected and since there is no response it won't start... :(
 
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