Where to connect a ground

[Electronics123]

Can someone tell me where the grounds in this schematic would be connected as a practical matter (where should the wires go)?
While I'm specifically interested in this schematic, I'm also interested generally.
Every circuit has a ground and the schematic usually just shows it floating around.
If the device doesn't have a metal chassis to connect the ground to, where should it go?
Is it always the ground plug of an electrical outlet?
But what if the device is battery powered?

 

[barry]

Can someone tell me where the grounds in this schematic would be connected as a practical matter (where should the wires go)?
While I'm specifically interested in this schematic, I'm also interested generally.
Every circuit has a ground and the schematic usually just shows it floating around.
If the device doesn't have a metal chassis to connect the ground to, where should it go?
Is it always the ground plug of an electrical outlet?
But what if the device is battery powered?

View attachment 182766

Ground is somewhat of a misleading term. A better term would be "common". Common does not necessarily have to be connected to the earth; it's just the reference point for everything else in the circuit.

As to "where it should go" it depends totally on the application; there's no one answer.

As far as your schematic goes, it doesn't make any sense. You've got your vertical connected across a 1K resistor that has no current flowing through it, and, therefore, has no voltage across it. (The transformer output is isolated, and your ground/common isn't connected to anything.)

Maybe you're not showing your whole circuit?

 

[Electronics123]

Maybe you're not showing your whole circuit?

That's the whole thing. I can't speak to whether it's drawn correctly or not. I think the way it works is that the Vertical and Horizontal get plugged into an oscilloscope and the two probes get connected to a component to be tested.

 

[FvM]

In the present circuit, ground connection is commanded by the oscilloscope inputs. That's a special case and not well suited to derive general rules for grounding.