Last night I was testing a TDA8703 analog to digital converter and after trying 36 MHz I tried 50 MHz on a whim and it worked. I also tried 60 MHz but the TDA8703 flaked off at that speed.
Here is a picture of the test setup.
This is what the LCD screen looks like.
Here is the video of it at 50 MSPS and 25MSPS.
Here is the schematic diagram.