Topband: lift station noise
Lee K7TJR
k7tjr at msn.com
Tue Apr 7 19:59:30 PDT 2009
Larry, for what its worth I have been through chasing noise from a pump
as well. Many of the newer systems use what is called a VFD, variable
frequency drive. Apparently there is some operating cost saving from
reduced power usage. Unfortunately these things rectify and chop raw
line voltages. The result is a lot of RF going back out the power lines. It
may be interesting to note that most manufacturers of such devices also
sell filtering devices to go with them. Unfortunately the manufacturer tells
no one that they may in fact be illegal to operate under some
circumstances so no one buys their filters. My local water company was
very helpful when informed of their noise emanations I was hearing over
a mile away on 160 meters. They installed the factory recommended filter
and most of the frying noise went away. You can still hear it when driving
by but not a mile away any more. I was successful by contacting the
owner of the pump. Hopefully that will work for you.
Lee K7TJR OR
More information about the Topband
mailing list