I'm working on an oscillator design using an off the shelf integrated circuit-based oscillator.
I have made two large gnd planes in the PCB, the top layer as well as the bottom layer.
Is this a good practice esp. for making PCBs for applications like oscillators?
I have also added plenty of vias to connect the two layers.
I just wanted suggestions (if any) before I send the PCB for fabrication.
For RF boards usually there would be vias right at the edge of the board as Wolfgang says, because the electric field can be terminated toward it (probably requires a textbook for a better explanation!).
The chip you're using (LTC1799) doesn't have particularly fast edges or clock rate, so I think you'll be OK, but worth adding in vias.
If it helps, there's a project using that chip here: Building a Fast Edge Square Wave Generator
(the output was connected to buffers to sharpen up the edges for that project). As you can see, I did as Wolfgang refers to, with the top ground plane pulled back where it wasn't needed. The top plane is really useful for preventing the board from warping, but occasionally gets in the way. I have the tiniest 50 ohm trace because the rest of it wasn't 50 ohm characteristic impedance.
