"N2EY" wrote in message
om...
| "Phil Kane" wrote in message
t.net...
| On Wed, 09 Jul 2003 03:02:43 GMT, Jim Hampton wrote:
|
| Phil, I doubt you're kidding, but a single wire with a ground
return? That
| is going to have a ton of problems even *without* putting
broadband on it.
|
| That amazed me too - but there's only one insulator on the pole
pig
| and one wire crossing the street to same. Three phase primary
is
| three wire, so there isn't even a Wye Neutral for return.
|
| I first saw this system along the Trans-Canada highway in
Alberta in
| 1970 and I put it down to the rural-ness of the area. But
suburban
| Portland in the 21st Century?
|
| Are there NO other wires on the pole?
|
| Here in EPA, most residential areas have three-phase going down the
| larger streets (like South Devon Ave. here in Wayne), with
| single-phase feeders going to the side streets. The return is partly
| through the dirt but mostly through the main messenger that carries
| the 120/240 twisted wires.
|
| Earth return will work fine, if the ground is good enough. The few
| HVDC lines that have been installed can be operated that way if one
| conductor fails.
|
73 de Jim, N2EY
The problem is, in most parts of the country the ground conductivity
is VERY poor. Just ask anyone who is familiar with commercial AM
broadcast station operation. They all wouldn't bury literally MILES
of copper wire around their towers in order to get somewhat of a
ground if they didn't have to. Besides our local electric utility
had nothing but big problems with 3-phase feeder lines without a
neutral along with the hot lines. They lose transformers whenever we
have a dandy lightning storm.

As far as BPL is concerned, BIG PROBLEMS LOOM for almost all licensed
services, including amateur radio if this is allowed.

73, Sam