I could go to the local farm supply, and mail you one for
less than $150! The only rub would be ours run on 120V, though
you can also get solar powered and battery powered fence chargers.

The usual fence charger puts out a pulse every second. The voltage is
probably 10Kv, judging by how far it arcs. The current is very tiny.

Back in the days of yore, the charger was a car ignition coil, and
the pulse timer was a pendulum. The power source was a battery. If
I were going to make one, I would use an old car ignition coil, and
a CMOS 555 timer to key an HV FET. A 6V lantern battery would easily last
a whole season.

-Chuck Harris

Roy Hammond wrote:
I like the simple approach - neon, SCR and transformer. But what transformer
would be sufficient but also safe?
Such electric fences are available here in the UK but unfortunately not for
the equivalent of $50 - more like $150!