fred wrote:Still, I'm finding very little info trying to search for others doing something like this. The opamp used in this image (LT6206) appears to be specifically for video signal amplification - is this required or could i perhaps use more commonplace opamps? I'll need to look up what kind of bandwidth rgb signals have, but I get the feeling that something like the generic TL07x with 3mhz might be too low.
Is this at all feasible to do? If not with generic opamps then at least with this specific one?
Yes, it's plenty doable.
For video purposes, opamps have two pertinent properties:
1- Whichever is worse of gain-bandwidth and slew rate. A gain of only 2 is a little low, so slew rate is more likely to be a problem.
2- Current drive capability.
You also need to match the "impedance" of the video cable that is used. In most video applications this is 75Ω. That's why there's a 75Ω resistor connected to Vin in your picture - to prevent reflections - as well as why there's two 499Ω resistors on both sides (a gain of 2) and a 75Ω resistor on the output stage.
For standard consumer 0.7Vpp video into a 75Ω load with proper impedance matching, you need an opamp that can drive 1.4Vpeak into a 150Ω load, or 9.3mA. (For Sync-on-luma/green or Composite, peak voltage and therefore peak current may be higher)
For baseband SDTV timing, a bandwidth around 3MHz (i.e. gain-bandwidth of ≥(3MHz·gain of2=6)MHz; slew rate of ≥(3MHz·1.4Vp·2 transitions per oscillation=9)V/µs) will be a little smeary but not too bad. Using my US TV's s-video input, I can see a maximum luma bandwidth around 7-8MHz (i.e. gain-bandwidth around 14-16MHz; slew rate of 19-22V/µs); anything more would be wasted. Your TV's SCART input may provide more bandwidth ... or it might not, since square pixels on PAL are roughly at 15MHz anyway, a bandwidth of 7.5MHz.