• Please review our updated Terms and Rules here

Using Extron 202 with Apple IIgs for VGA output

bitfixer

Veteran Member
Joined
Apr 6, 2011
Messages
672
Location
San Francisco, CA
Hi all,

I recently bought an Extron RGB 202xi video interface unit, and I am attempting to use it to view the video output from an Apple IIgs on a VGA monitor.
Not sure if anyone has any experience trying this, but I've had some difficulty getting to work and was wondering if anyone had tried this before. I have a makeshift cable between the DB15 connector and the 9-pin input on the Extron with the connections I think are right, but I'm not completely sure. Also I have a 5-BNC to vga cable connecting the output to a vga monitor.
In particular what I'm seeing is that when the hsync and vsync frequencies are displayed, both show approx. 15.7k rates - which is correct for hsync, but not vsync. At the moment vertical sync going into the extron is not connected to anything, and the composite sync from the IIgs is connected to the pin for Hsync/composite sync on the extron.
Any help appreciated, thanks!
 

bitfixer

Veteran Member
Joined
Apr 6, 2011
Messages
672
Location
San Francisco, CA
Hmm, I'm starting to think that the Extron won't work with the IIgs at all. I don't see any evidence that the extron does any scan rate conversion, so I don't think the IIgs horizontal frequency will work with the VGA monitor. Not encouraging..
 

RWallmow

Veteran Member
Joined
Oct 19, 2006
Messages
1,791
Location
Anoka, MN USA
I have used an extron box (not sure on model, not at home now) to do just this and it worked fairly well on a crt but looked aweful on an lcd. I will get and post the model later when I'm back home.

Edit: since I have 3 monitors that natively work on my IIgs I would even consider selling my extron with the extron IIgs cable.
 

RWallmow

Veteran Member
Joined
Oct 19, 2006
Messages
1,791
Location
Anoka, MN USA
Thanks, I would be very interested in hearing about how you got this working.
It was an "Extron RGB 118 PLUS" and it lists IIgs right on it as a supported system, and the listed cable for a IIgs is the Extron number "26-018-02"

Like I said it worked decent on an CRT monitor, looked OK (some flicker, but it is an interlaced mode, so that's expected), but on a LCD it looked like garbage with the "scaling" that LCD monitors do to stretch the picture to fill the screen, LOTS of artifacts.

EDIT: I was able to find my Extron 118 (and got the cable # info off it), but I cant seem to find the cable at this time, but its probably packed away with my IIgs.
 
Last edited:

Lutiana

Administrator
Staff member
Joined
Mar 26, 2009
Messages
3,223
Location
Dublin, CA USA
Extron has thousands of different devices, so the model number on RWallmow's Extron box would be key.

BTW all the manuals are still available from Extron. Apparently it will do CGA and EGA input, 15-150Khz, and scan convert it to RGB (component) or RGBHV (VGA) with 300Mhz worth of bandwidth. So it sounds like it should work, so I'd make sure you have the Extron configured correctly and double check your makeshift cable.
 

njroadfan

Veteran Member
Joined
Jan 21, 2011
Messages
1,542
No experience with Extron in particular, but any scan doubler or scan rate converter should work fine with the IIgs (or Amiga or Atari ST as they all output 15.75khz RGB). The video shouldn't be treated as interlaced either as the IIgs outputs "240p" video at NTSC timings. Some scan doublers (particularly the ones designed for TV signals) sometimes treat it as 480i and create ugly interlaced output. I own a Micomsoft XRGB2+ for scan doubling tasks and it handles the IIgs RGB video without a problem. Compatibility is a problem with some LCDs, but I haven't encountered it with any of my monitors yet. The newer XRGB3 avoids this problem since it has DVI output. Both units go for hefty prices as they are rare outside of Japan and highly sought after.

The Highway 100 scan converter is a readily available option and it is known to work with the IIgs. There are tons of SCART to HDMI boxes on ebay for sub $100 prices that may work, but are untested. Another option if you have a TV with component input is to use a RGB to YPbPr transcoder such as this, commonly known as the Cypress CSY-2100. The box is strictly analog, no analog-to-digital-to-analog steps in that chain.

More info can be found here for those interested in this topic.
 
Top