Actually I don't wish it to be so, I'm just trying to figure it out and speculating based on my understanding. And frankly I don't understand why you guys consider these two specs to be so vastly different.
Here's what I read about EGA on Wikipedia:
1 GND Ground
2 SR Secondary Red (Intensity)
3 PR Primary Red
4 PG Primary Green
5 PB Primary Blue
6 SG Secondary Green (Intensity)
7 SB Secondary Blue (Intensity)
8 H Horizontal Sync
9 V Vertical Sync
Signal
Type Digital, TTL
Resolution 640h x 350v x 16c, other modes available
H-freq 15.7/21.8 kHz
V-freq 60 Hz
Colors 16/64
And here's what the manufacturer says:
Specifications:
Resolution........................................ 512 x 342
Horizontal scan rate.......................... 22.3KHZ, (4µs on, 40µs off)
Vertical scan rate ............................. 60HZ (180µs on, 16.4ms off)
Output level (all lines) ......................TTL Positive
Video Connector Pins (pin out)........1-2 gnd; 3-4-5 RGB; 8 Horz; 9 Vert.
Power Consumption ........................0.25 watts from Mac power supply
When I compare the two, I see all of the pin signals line up, except for the intensity, one of which is a ground, the other two unassigned. Without any knowledge to the contrary, I would guess that a monochrome signal does not need intensity, that it applies only to color – why else would a monochrome TTL output supply RGB if not to be compatible with EGA? Then I look at the resolution and have to question whether the specs are visible area or actual area. I simply do not know, yet I know EGA will accommodate it. Finally, I see a mere .4kHz difference between the horizontal scan rate and wonder if that is tolerable.
Bunsen, since I do not know, I am asking in the form of speculation because I have not yet gotten a clear answer as to why the specs are totally incompatible when they seem so similar. You are the expert here, not me. So I apologize if it sounds like I am challenging you, in actuality I am encouraging further details. It's times like these when I wish I had an engineering background, but I don't. So I appeal to the collective membership for their good natured indulgence.
Your point is well taken that events of the past do not always make sense with what we now know, yet were perfectly sound at the time. Nevertheless, PowerR managed to make it into the 21st century, so all of their decisions weren't bad.
It would seem, based on your emphatic assertions that in any event this adapter is truly only compatible with specific LCD & CRT displays which used a unique standard to this adapter only. Which means the mission now is to try to locate them, or discover a way to adapt it further.
Finding a spare CGA or EGA monitor lying around is a bit more difficult to test it with, so I was simply trying to assess if it was even worth the effort. In any event, Bunsen, I bought the thing because it was in my hemisphere and would not have had to pay the colossal shipping you would have incurred and because you expressed an interest in finding out more about it. Now I'm wondering if I should have bothered.