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I'm trying to convert arcade video signals (JAMMA) to VGA specifications.

From what I've gathered, arcade video signals aren't standardized. They can range from 0v-2v or 0v-5v, etc. However, VGA requires 0v - 0.7v p-p (75 Ohm double terminated).

Are there any ICs that can detect RGB voltage and then convert it to VGA level?

Can anybody give me any advice?

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  • \$\begingroup\$ Nothing on ebay? \$\endgroup\$ – Gregory Kornblum Jul 26 '19 at 18:30
  • \$\begingroup\$ RGB to VGA was a very big thing, back when RGB and VGA were big things. Have you googled? If it's just a level conversion thing, you may be able to get by with attenuators. \$\endgroup\$ – TimWescott Jul 26 '19 at 18:32
  • \$\begingroup\$ It appears to me that JAMMA does have video standards. Have you really searched for the JVS? Judging by the appearance of similar products on the usual Amazing shopping sites, the conversion will take more than just an IC, \$\endgroup\$ – Elliot Alderson Jul 26 '19 at 18:43
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    \$\begingroup\$ Not sure of source impedance. If you can see the signals are 2V and you make a Thevenin Equivalent at 1.4V @ 75 Ohms then when terminated , it will be 0.7V THis might only be approx a 150 Ohm series R to VGA for each RGB. ( 150+75)/75 * 0.7 =2.1 V \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jul 26 '19 at 19:06
  • \$\begingroup\$ If you could actually examine the signals on a scope and determine their levels and that the timing and synch schemes and interlacing are compatible then you could presumably use a resistive voltage divider. But it's quite likely that the incompatibilities go beyond this. It's possible that the sampling stage in a VGA-in LCD monitor might have more flexibility. \$\endgroup\$ – Chris Stratton Jul 26 '19 at 19:08

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