Another method to interface classic computer to a standard VGA monitor would be to use an Extron 202xi converter ( Other models may work, I used this model). You can still find these old boxes out there for $30- 80. This model can handle ECL inputs, which was why I chose it for my application. My application was to connect a standard VGA monitor to a SUN 3/140 that had a dying ECL monochrome CRT 1152x900 Horiz=61.8KHz Vert 66Hz ( model M19P114) attached to it .You have to make a custom cable between the computer and the Extron input ( Because the Exton DB9 inputs are weirdly configured), the manual for the 202xi box is at the Extron website. When making my cable from the Sun to the Extron, I had to keep it very short ...6 inch...because the ECL had a problem with long cables. The results were amazing, very nice output from my SUN on the VGA monitor ( HP L1925). The Exron has 5 BNC outputs RGBVH, so I also had to buy a 5BNC to VGA cable, Amazon , about $10. Hutch On Mon, Apr 15, 2013 at 8:43 AM, Matthew Stock <stock at csgeeks.org> wrote: -- e-?

I used the same cable that was originally connected to the original CRT monitor. The cable was at least 6 foot long, straight through DB9 on both ends. I was getting blurring and ghosting on the VGA monitor using this long cable. I did not have any terminations once I connected the Sun to the extron 201xi. perhaps I could have put some terminating resistors on the end of the cable connecting to the Extron. The 6 inch cable with unsheilded straight 20 guage wires worked just fine. I found a schematic for the frame buffer card in the SUN, and it had a resistor termination scheme along with the 10H131 chips , but not sure what's at the Extron 202xi input. The just sharing with the group the results. I'm sure improvements could be made to allow for a longer cable. On Tue, Apr 16, 2013 at 3:02 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote: -- e-?

I am sure you are correct. I will try to find that schematic of the frame buffer card, and see what resistors were used on the ECL source end. Now you have me wanting to put that long cable back on with the correct termination! On Wed, Apr 17, 2013 at 4:12 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote: -- e-?

On 04/16/2013 03:02 PM, Tony Duell wrote: Unless my memory is failing much more severely than I think, the OP said he's running a 3/140, and the 3/140 has an onboard *color* framebuffer whose outputs are analog RGB with separate sync, not ECL. Quite a few Sun framebuffers have ECL outputs, but they're all very old ones (older than the 3/140) and all monochrome. It was not at all uncommon to drive those monitors through fifteen or twenty feet of cable; I still have some of those long cables somewhere. -Dave -- Dave McGuire, AK4HZ New Kensington, PA

On 04/17/2013 04:39 PM, Jochen Kunz wrote: Oh yes, I remember those! They didn't last very far into the SPARCstation era, if memory serves. Those monitors are getting really tough to find. I'd like to have a few for my 3/60s. What are the characteristics of those terminators? I wonder if that's the OP's problem as Tony suggested. -Dave -- Dave McGuire, AK4HZ New Kensington, PA

On Wed, 17 Apr 2013 22:21:29 -0400 Dave McGuire <mcguire at neurotica.com> wrote: I can't remember. I came across this when I got my logic analyzer 15 years ago. I got it without propes and build my own probes from MC10124 ICs. Most likely I am thinking about / confusing it with the MC10115 / MC10116 line receivers. -- \end{Jochen} \ref{http://www.unixag-kl.fh-kl.de/~jkunz/}