| S-Video |
| S-Video in an interface that carries luma (black and white) information and chroma (hue and saturation) information on separate wires. This interface is free from the cross color and cross luminance of conventional NTSC composite multiplex. |
| This modification gives the GR-2000 a composite input and accesses the luma and chroma inputs of the GR-2000 separately so the set can display S-Video sources to full advantage. |
| The schematic is simple enough to follow. Heathkit designators are used for all original components. CMOS switches reconfigure the circuit from the original receiver format to the composite input or S=Video input. Vref is adjusted so the black level of the composite source matches the black level of a received TV station. The circuit was constructed on a Radio Shack board that matches the layout of a plug in prototype board. None of the wiring or layout is critical. |
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| How well does circuit work? Picture quality is excellent from composite and S-Video sources. |
| The set's delay line is the component that most limits the horizontal resolution. With an improved delay line, good to 10 MHz, the horizontal resolution of the modified set exceeds that of any source. The horizontal resolution of the modified GR-2000 is over 800 TV Lines. In the first screen shot notice the vertical and horizontal lines are the same width and intensity. There is no ringing or harsh edges on either side of the vertical lines. In the second image note 5 MHz is resolved and the lower frequencies start and stop cleanly. |
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| For more information on the design of this delay line see my delay line page. |
| This set is in regular use with an ATSC set top box feeding the S-Video input. I was given the set by a friend and I used it very little until 2002. The kit had been built by a friend's mother in her 70s and used by her until her death. |
Send questions or comments on this page to David Carlstrom.