Saturday, 28 January 2012

Building a high-quality test cable

For a while now I've been wanting to build a high-quality VGA to SCART test cable that only has video and no audio. The reason for no audio is that I have a collection of SCART to RCA cables that have 6 individually shielded wires. Here's an example of what I'm talking about:

I figured that since there are 6 RCAs that was just the right number to build a video only cable: red, green, blue, H-sync, V-sync and 5v to enable. Having the RGB lines individually shielded should theoretically provide better quality. Who knows... hard to tell in practice. Either way, I at least wanted to build an extra cable so I could try and get dual displays going and, hopefully, test TVs side-by-side. I took the opportunity to practice some neat heat shrinking work and generally make things as tidy and accurate as possible. Here's a few work in progress shots:

Composite sync circuit
Wires trimmed, shields heat shrunk, pins soldered
SCART plug fully loaded

 Completed VGA wiring
And... it worked! Street Fighter III in action.

Since this was the first time I'd actually bothered to systematically measure the lengths of each wire and accurately cut the heat shrink to length, it took me a LONG time to get things this neat! I have to say, after spending the best part of 3 hours on this exercise, I was mighty relieved when I hooked the cable up and it worked perfectly straight away!

No comments:

Post a Comment