I saw this voltage booster module on the web,

What voltage booster?

 

What voltage booster?

Sorry, I forgot to add photos.
This one I mean. Can I just connect one wire to the fence and the other to ground?

 

Can I just connect one wire to the fence and the other to ground?

Likely only if you want to kill something.
To be safe a electric fencer needs the voltage to be interrupted periodically, such as once a second.
Otherwise it could be lethal.

 

Likely only if you want to kill something.
To be safe a electric fencer needs the voltage to be interrupted periodically, such as once a second.
Otherwise it could be lethal.

Yea, I know that and you're right. It needs to be periodically, otherwise you can let the wire if you grab it.
But I will fix that with a relay or transistor, my question is only can it work that way, one wire to fence ,onde to ground?

 

Can I just put one cable into the earth and the other on the fence cable?

Yes - that's how it's wired. The capacitance between wire and ground stays charged up between pulses - especially in dry weather. As the stored energy is C.V^2/2 even a few pF stores quite a bit of energy

 

Depending on where you are located you can find a lot of products to do this, for example, in the US:

https://www.tractorsupply.com/tsc/catalog/electric-fencing

But, in any case, the way to do it is to buy commercial products, the complexity of safety related things and all the details of a successful deployment make homebrew very dodgy unless you didn't have to ask this question.

They should create a forum for people to learn how to build circuits so they will know how to do it safely.

 

Here is an old(er) thread also on the subject, the one I show uses a auto HV coil and is not lethal.
https://forum.allaboutcircuits.com/...or-ignition-coil-project.191664/#post-1795729