Lead Length Problem

I discovered that the length of the leads connecting the TC-255 chip to the circuit board is a limiting factor. I found after assembling my quickcam with six inch leads using 26 gauge ribbon cable that the images obtained were the dreaded "all white" images. Fortunately, I tested the CCD chip without the extension leads and it tested fine. Here are some test leads of varying lengths that I made up and the results:

6 inch - 26 gauge: Bad, all white images

6 inch - 22 gauge: Bad, all white images

5.25 inch -22 gauge: Bad, very faint screen draw in upper left corner of image display

4 inch - 22 gauge: Bad, faint screen draw in upper left corner getting larger

4 inch - 4 conductor 26 gauge double shielded data cable from Radio Shack: Bad, all white images

4 inch - 30 gauge wire wrap: Bad, all white images

3.25 inch - 22 gauge: Bad, screen draws are darker on left side of image display and white "noise" spots streak to the right.

2.75 inch - 26 gauge: Bad, screen draws are darker on left side of image display and white "noise" spots streak to the right.

2.75 inch - 22 gauge: Good, all okay

1.5 inch - 26 gauge: Good, all okay

Conclusion: I was just barely able to install the 2.75 inch - 22 gauge leads and the camera works fine. With leads that are too long, the timing of the circuit is affected. My next test would have been to try to obtain high frequency cable. If I were to build another camera I would use even shorter leads from the CCD chip to the cirtcuit board by routing them out the side of the cosmetic jar instead of out the back.