I was just wondering wether the overhead 11Kv and 433 volt wires which run near to high power (50 KW or more) MF transmitter sites especially feeds to nearby houses or farms need some kind of chokes or capacitors to get rid of the RF which will be on the lines to see what I mean have a look at pictures of the stagshaw transmitting station on mb21 site
You may find these old BBC tests the of the field strength around the stagshaw transmitter of interest. about half a volt per metre at 5km with 120kw radiated. We might expect 5V/m at 500m, and much closer than that and you are within the site boundry.
Pick up of a few v/m on a single frequency that does not propagate through the transformers is not a big deal.
MW broadcast is not normally as powerful as you may think, Radio 4 at half a megawatt is very unusual, and pretty much covers the whole country 100kW or less is far more common.
The prime mover for 50kW might be a single water cooled triode the size of a domestic teapot, or perhaps a pair in push-pull with 10-20kV on the anode and capable of 10A peaks.
Cooling water runs hotter than a domestic shower though, and has to be de-ionised and run through a few feet of hose to shake off both the RF and the DC before it hits the pumps and the heat exchanger.
Semiconductors are getting there, but pallets of couple of KW are very expensive and hard to combine.
You may find these old BBC tests the of the field strength around the stagshaw transmitter of interest. about half a volt per metre at 5km with 120kw radiated. We might expect 5V/m at 500m, and much closer than that and you are within the site boundry.
Pick up of a few v/m on a single frequency that does not propagate through the transformers is not a big deal.
MW broadcast is not normally as powerful as you may think, Radio 4 at half a megawatt is very unusual, and pretty much covers the whole country 100kW or less is far more common.
The prime mover for 50kW might be a single water cooled triode the size of a domestic teapot, or perhaps a pair in push-pull with 10-20kV on the anode and capable of 10A peaks.
Cooling water runs hotter than a domestic shower though, and has to be de-ionised and run through a few feet of hose to shake off both the RF and the DC before it hits the pumps and the heat exchanger.
Semiconductors are getting there, but pallets of couple of KW are very expensive and hard to combine.
