Wiring schemes and kind of cable for connections vga monitor.

The connection of the R, G, B and sync signal shoul be made using 75 ohm coaxial cable. If you happen to use any other type of cable you will quite propably see a radical drop in picture quality (loss of details, shadowing etc.). A cheap computer grade cable might work on 640×480 resolutions, but will not difinatly work well on 1024×768 at 75 Hz refresh rate.

            Red Video  (1)      Red Return (6)
            Green Video  (2)    Green Return (7)
            Blue Video  (3)     Blue Return (8)
            H Sync (13)         Ground (5,10)
            V Sync (14)         Ground (5,10)

Tips Wiring schemes and kind of cable for connections vga monitor.

The magic in this circuit is that it can take HSYNC and f VSYNC at any polarity and can still make valid composite sync signal out of them. The  principle of the circuit is the following: R1 and C1 form a low pass filter, which outputs constant logic 1 or 0 level depending on input HSYNC polarity. The first XOR port combines this signal to incoming HSYNC signal to form a HSYNC signal that is always active at logic high. Same type of processing is done also to VSYNC signal with R2, C2 and one XOR gate. Then those processed sync signal are combined with one XOR gate. Finally the resulting CSYNC signal in inverted with one XOR gate to make it to have the right polarity.

Tips Wiring schemes and kind of cable for connections vga monitor.Tips Wiring schemes and kind of cable for connections vga monitor.