[Lowfer] Report and Order

[N6IO]

My understanding is that only long-haul and some regional "distribution"
lines carry PLC.   I suppose I need a better term for lines that carry
PLC.  We need an easy way to identify them since UTC seems to consider the
location of these lines to be secret.  Lines that supply power to customers
would not use PLC.

I've seen some reference to PLC running on 100KV and higher voltage lines.
I suppose there is some standard size of insulator being used on these
lines - I suspect that if the insulators are shorter than 1 foot they
wouldn't likely carry PLC.   It might be better to have the rules just
specify a distance from lines carrying PLC and make it the responsibility
of the utilities to let hams know which those are.  Typical lines that feed
customer transformers are 1200v. and just have 1 or 2 insulators. Lines to
typical local substations would run 12kv.  In the R&O it mentioned there
are 2200 PLC systems in the US - so the vast majority of lines do not use
it.  My guess is any line on a single wooden pole would not.

Maybe they can publish a power line spotters guide.

100 M separation is about the best we can hope for based on some
interference studies published back in the 80's.

Craig - N6IO


On Thu, Jul 9, 2015 at 8:49 PM, Eric Smith <esmithmail at gmail.com> wrote:

> 100m from transmission lines?  That's a whole block.  This must mean
> high voltage long haul lines, not the distribution lines that run
> along many city streets?  For many folks it would be impossible to get
> 100m from these distribution lines if the transmitter has to be at
> your house (not portable).
>
> So must mean the high voltage long haul lines?  Otherwise I wouldn't
> suggest the 100m ..
>
> > On Jul 9, 2015, at 7:40 PM, N6IO <n6io at wasson.com> wrote:
> >
> > If I am reading the July 7th FCC WRC-07 Implementation Report and Order
> and
> > WRC-12 Order correctly, the 2200 meter band is officially allocated as a
> > new ham band.  Operation will not be allowed until the FCC adopts service
> > rules after reviewing comments on the previous NPRM.
> >
> > This is very good news.  Interference potential at 2200 meters is higher
> > than at 630 meters, so it seems very likely the 630 m band will also be
> > approved.
> >
> > I'm thinking that reply comments should focus on what these service rules
> > will be.  In the report the FCC again mentioned not allowing mobile
> > operations, but only fixed operations.  I don't see the benefit of not
> > allowing portable/mobile operations as long as a distance limit from
> > transmission lines is established.  So my comments will focus on how far
> a
> > transmitter must be (100 M) from these lines and why with 1W EIRP
> > interference is not possible at that distance.
> >
> > The report also mentioned limiting antenna height, but since the power
> > limit is based on EIRP this makes no sense.  A short antenna can produce
> > the same radiated signal strength as a tall antenna if power is adjusted
> to
> > meet the 1W EIRP limit.
> >
> > At 630 m the FCC has the option of allowing 5W EIRP - I think we should
> > encourage that.  At the higher power level it might be necessary to
> > increase the separation between antennas and transmission lines to 500 or
> > 1000 meters to allow for an extra 7 db of isolation.
> >
> > Is this how others read this Report and Order?
> >
> > Craig - N6IO
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