Found a modern day field sequential color tv

[Dave A]

I took mine to our DVHRC monthly meeting tonight for opinions on how it works and I got a bunch of input. I had not looked at the manual much since this started and we looked around.

The first thing spotted is that the CRT...all 4.5"...operates at 12kv. That is a lot for a mini monitor but this set was sold as a daylight useable monitor. Bright outside with high resolution. That helps explain the 12kv and also the CRT having to be bright behind a bunch of dark LCD filters. The "blue only" button on the front gives a true view of the blue image as it passes. The R and G should be the same and as dark.

And hidden in the block diagram is a square noting the "sports killer" in the V blanking box. Our translation specialists converted this to "shorts killer" which makes sense. Kill the beam on a sweep failure at 12kv so a single beam sweep does not laser off your arm.

The next question was how do they do the RGB at the tube to sync with the RGB LCD in front of the BW tube.

The block diagram suggests video buffers ahead of the CRT and sideways to the LCD shutter conversion to be re-combined later in front of the screen. 1gig worth at the CRT. 512 at the LCD conversion. We think the buffers show the video on each frame in sequential RGB at the CRT to sync with the LCD doing the same. The LCD takes over from there to make color minus all the artifacts of NTSC. So clean and pure.

We think that the usual 30 frame/sec rate is tripled so each frame can do the RGB information at the tube inside 1/30 sec. That means this set does 90 frames per second via the buffers at the CRT to get you a complete RGB color frame in 1/30th of a second for the LCD to parade along with at the same rate.

Comments welcome.