Solid state ColRTel, NTSC field sequential color + Shrek

Описание: Refined version:    • Solid state ColRTel improved, NTSC field s...  
Doom on world's smallest CRT:    • World's smallest 0.5" B/W crt monitor in c...  

Inspiration: http://www.hawestv.com/mtv_color/colr...
Project schematic: https://oshwlab.com/radiohonza/transi...
In this video I grant a small monochrome CRT from portable TV the ability to display color image using a rotating color wheel and circuitry similar to the Col-R-Tel color adaptor from the 1950s.
The Col-R-Tel module is built using purely transistors, no ICs, and with easy to get components. Its principle lies in demodulating only one color signal at the time, based on the filter color in front of the CRT. This is done through switching different carrier (color burst) phase offsets coresponding to R-Y (90°), B-Y(0°) and G-Y(236°). The selected carrier phase is summed with the chroma contained in the NTSC videosignal resulting in an AM signal amplitude of which is corresponding to the demodulated color difference signal level. This AM signal is then simply detected by a synchronous detector, combined with the luminance in videosignal and sent to the CRT.
The module also contains a vertical sync separator, off delay (for achieving dutycycle around 50%) and a simple phase comparator comparing vertical scan frequency with the wheel speed giving off a PWM signal for motor speed control. By spinning the wheel at speed exactly the same as the vertical refresh of the video signal (in vertical sync) and each time displaying different of the 3 RGB components we achieve full color image.

0:00 - Converter details
0:24 - Shrek in field sequential color
2:37 - Setup overview