Pinout on 23 pin RGB to 15 pin VGA?

[TheBilgeRat]

Anybody have the pinouts for a 23 pin RGB to 15 pin VGA adaptor?  I'd like to do a DIY since I have the pieces parts.

[TheBilgeRat]

Yes...

Care to share it?

[TheBilgeRat]

The Amiga RGB pin out is here: http://www.ntrautanen.fi/computers/hardware/misc/amiga_rgb.htm
VGA pin out here: http://www.l-com.com/content/Audio-Video-Tutorial.html

I built one and linked the RGBs, the H and V syncs and a ground.

the analog or digital RGB?  Also, that link suggested that modern monitors want something on the 15 pin.  VGA pinout says its a data clock... Wonder if pin 1 on amiga 23pin and pin 15 VGA would be happy together...

[TheBilgeRat]

sweetness - +5V, gnd, R, G, B it is, then!

[TheBilgeRat]

R, G, B, VSYNC, HSYNC, and GND.

No +5V.

Yikes!  my bad - will rock it proper.

I'm still at "pulling the really stuck 23-pin terminals out of the ancient plastic block" phase of the operation.

[TheBilgeRat]

Some CRTs reportedly load the sync signals too heavily. If Miggy fails to boot up, don't be alarmed - you'll need to add serial resistors or add a transistor for signal boost.

I just got an Idek 17" that is probably doing this right here - All I get is flashing green power light with it attached.  would I put resistance on both sync lines?  If so how much?

[TheBilgeRat]

So, after a bit of research I came across this link for anyone else in my predicament and who wants to build this thing on their own:

http://amigadev.elowar.com/read/ADCD_2.1/AmigaMail_Vol2_guide/node015E.html

It looks like the original Commodore converters used a 74HCT08 as the intermediary in the Hsync/Vsync side and powered it off the +5 on the amiga side.

Of course, you could always buy it from Amigakit :lol:

But I've come too far already!  Damn the torpedoes!

[TheBilgeRat]

In fact, just in case amiga.org outlives that site, here is the diagram and its info:

A1-A14 are pins 1 - 14 on 74HCT08.
C1 is a .01uf 50A ceramic capacitor.