Video is generated from red green and blue sensors at a certain percentage. At gray scale or no saturation we used to have to set gray balance where there was no color showing. Then at max saturation we had to set white balance for the same.
A sync generator produces vertical sync pulses (slightly less than 60 cycles) and horizontal sync pulse. The vertical pulse starts the whole screen and horizontal starts each scan line of 600 more. With NTSC this is done at about 60/per second. Then a burst (3.5 MHZ) had to be generated to sync the color oscillator in the monitor.
To produce composite or comp video the colors sync pulses and burst have to be added together in phase with a multiplexer.
Some laptop computer video boards to not have the multipleexer and the cheap adapter doesnt work. They usually have a s-video output. S-video uses a separate conductor in the cable. In high quality video this is for more bandwith for better color etc. With karaoke gaphics it is not required.
This is a Targus ACP50 docking station It originally sold for $150 I think I got this one on Ebay fo less thn 50.
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From lefet to right.. Mic, stereo out, RS323 serial, RJ-45 Ethernet, then the vga out. The rest is a USB hub 2 powerd and 2 not powered , on/off switch. On the right the usb cable to the laptop and power cord.
Now your adapter will work I use tihis one which puts out s-video or comp and L/R stereo.
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