Ext bus digital ground/analogue ground?

[Ergot_Cholera]

I have a Kindo PAL 50/60 TV Booster that I am going to attempt to mod for RGB. I have checked that the pins that are required are all there (there are only the bare minimum of pins unlike on a Tennokoe 2 which has all 69 connected), but it seems that the main ground plane is connected to digital ground and only one pin is connected to analogue ground. What is the difference between the two?

[wilykat]

generally analog ground is for connecting to ground shell of audio and video cables and digital ground is for the electronics like Tennokoe 2's SRAM chip.

[Ergot_Cholera]

Obviously there are no memory chips inside this unit as it is used to create a PAL RF signal from an NTSC signal, so it should be okay to use digital ground shouldn't it, or would it have a negative effect on chips within the console itself?
The RF unit that I have now removed (along with most of the components) was connected on the ground plane to digital ground.
I might try connecting pin 21 of the SCART to analogue ground or maybe try both ground points and see if there is more or less noise on one or the other.