Posts Tagged ‘2200m’

LF / MF – Time To File


The FCC is now officially inviting comment on its proposal to establish two new amateur bands ... the 2200m LF band (135.7kHz - 137.8kHz) and the 630m MF band (472 - 479kHz).

The detailed proposal was published in the Federal Registry on July 2, thus establishing the comment deadline as August 31st and a deadline of September 30th for 'comments on the comments'.

It is proposed that the Amateur Radio service would be 'secondary users' of this slice of the spectrum. Secondary users must not cause interference to the Primary users and also be willing to accept interference from the Primary users as conditions of operating. In reality, the only primary use of these bands in North America is for hydro distribution control (PLC) signals. Over several years of maximum ERP amateur experimental work, both here in Canada as well as in the U.S.A., there has been no documented interference to these signals nor have the well-shielded PLC signals been a problem for amateurs ... it seems that co-existence is readily attainable.

Whether you have operated on these bands or not (but especially if you have), I would urge you to file a comment expressing your opinions on any of the critical concerns (antenna height, power etc.) expressed by the FCC. All of these were listed in a previous three-part blog, starting here.

If you think that you might like to operate or experiment on either of these bands in the future, then just tell them that as well ... the more interest from the amateur radio world shown, the better.

For those of you that might think that this part of the spectrum has little to offer the amateur, I can assure you that such is not the case. Coast-to-coast propagation has been demonstrated on numerous occasions (on both bands). Both bands offer wide opportunities for experimental work dealing with antennas, modes and propagation as well as providing an abundance of homebrewing opportunities for builders.

Comments may be filed, identified by ET Docket No 15-99 (proceeding number), via the FCC Electronic Comment Filing System (ECFS). As well, you can read all of the comments that have been filed here.

U.S. amateurs have been waiting long enough (since 2007) for an opportunity to use these bands ... let's show the FCC that we really want them by filing your comments before August 31st!

U.S. LF Bands – Rulemaking Ruminations (Part 2)

(...cont'd)

* TWO: We need more technical showings this time, with as many solid
details as possible. I hope the Part 5 licensees are prepared to crunch
numbers, but those of us who only monitored are also able to contribute.
(Much more on this in future correspondence, I expect.) In par. 169. the FCC enquires: "to meet our goal of providing for the coexistence of amateur services and PLC systems in these bands, we seek detailed comment on the technical characteristics of both the PLC systems and the amateur stations.
This information will allow us to set an appropriate separation distance."
The very next sentence, though, I recognize as a somewhat worrisome bit of FCC-speak: "Although the Commission in the WRC-07 NPRM inquired into the technical rules and methods that would assure coexistence, commenters provided little in the way of concrete information." Read that as said with a slightly scolding tone, but with a facial expression that says they're keeping an open mind.

The utilities, IMO, provided no concrete technical information at all. ARRL
cited the 1985 NTIA study on which the 1 W EIRP and 1 km separation idea is based, but the FCC is concerned whether that's still valid. Well, one would hope that any changes made to PLCs over the past 30 years would be toward making the system more robust, not more vulnerable to evildoers, accidents, and natural disasters, but this could prove an area of contention. That may be something the big guys have to fight out; I don't know how much we as individual licensees or observers can contribute. But there ARE other technical matters the FCC needs and wants to know, which we may be able to furnish.

For instance, what sort of PLC signal levels have we actually experienced in the proposed bands? How serious were their impact on licensed activity, and how have PLCs been coped with in actual operation? Also at paragraphs 171, 178, and 178, the FCC is asking for some really fundamental, crucial data.
Namely: What sort of power levels have the Part 5 licensees actually
radiated, and at what actual separations from transmission lines? What
maximum size should an amateur antenna be, and--the biggie, in my view--what is the efficiency of both "typical" and potential amateur antenna systems?
(The Commission would like us to include information from Canadian and
European hams on these issues as well. Details of amateur practice in the
rest of the world could be very helpful in formulating rules here.)

Those operators who have the capability of measuring their true field
strength are in an especially excellent position to help quantify current
practice. Those who can't do that, but are able to measure their ground
losses accurately, can make reasonable calculations to show the maximum
efficiency possible with antennas of various heights. That's likely
preferable to doing it all in NEC modeling, since not all such software is
really good at predicting ground system losses, especially at LF. I'll
gladly offer my own ground system's resistance numbers to anyone who wants to do the math, for instance, as its 32 radials of 104 to 135 ft length in 15 mS/m soil are probably representative of a fairly decent ground for
antennas up to 100 feet high...and I'll be doing another set of readings
very soon, which can include measurements at 2200 m this year in addition to the runs I routinely do at 1750 m.

* THREE: At 172, the FCC observes: "If we were to adopt our proposal to
permit amateur operations only when separated by a specified distance from transmission lines, when a new transmission line is built close by an
amateur station, the station either would have to relocate farther away from the transmission line or cease operating." Scary, huh. But they go on to ask: "How should our rules address the potential for new transmission lines to be constructed closer than the specified distance to pre-existing amateur stations? We do not want to inhibit the ability of either PLC systems or amateur services to grow and expand without imposing unnecessary burdens on either. Is it possible for utilities to refrain from geographically expanding their PLC operations within the relatively small portion of the 9-490 kHz band that we are making available for amateur operations, and is this something utilities would do on their own accord, given the Part 15 status of PLC systems? Should our rules explicitly prohibit utilities from deploying new PLC systems in these bands?"

My answer: yes, please. Look back at par. 26, in the WRC-07 R&O section
where the Commission explains their basis for adding the 2200 m allocation:
"We intend to structure these service rules to promote shared use of the
band among amateurs and PLC systems. Amateurs will not be able to use their allocation status to force unlicensed PLC operations out of the band, and utilities will have no cause to abandon or incur large costs to modify
existing PLC systems." Read that again: "Amateurs will not be able to use
their allocation status to force unlicensed PLC operations out of the band."
That's the reality of the matter, and yet I think it also works in our
favor.

So far as I know, this situation is unique in the history of radio regulation. I can't think of another example where an incumbent, but unlicensed and unallocated, user of radio spectrum has been afforded such protection from any allocated and licensed service. However, most of us who commented in the 2013 proceeding DID AGREE with the Commission that PLC technology has been a special case for a long time, and most recognized that acceptance of its existence was the only way to move the discussion off dead center and get to the point where we are now.

But I maintain this coin has two sides. If we in a licensed, allocated service are willing to accept that we cannot displace existing PLCs now or in the future, then it is ONLY FAIR that the unlicensed, unallocated users should not be able to displace the licensed users, either, now or in the future. Otherwise, it is not truly sharing.

The only way I can see to guarantee protection to licensed users, comparable to what the unlicensed ones will have, is to incorporate within Part 15 a prohibition on any changes in power, transmission mode, and route of existing PLC systems, or installation of new ones, within a reasonable band centered on the new amateur allocations. That achieves the stated goal of not displacing existing systems or burdening the utlities by forcing any changes to them, while only removing two small slices of spectrum from consideration for future installations. That seems an entirely reasonable compromise to me.

Your comments are welcome--and essential!

73
John Davis


You can view comments as well as file your own, via the link from this page:

http://apps.fcc.gov/ecfs/proceeding/view?name=15-99

U.S. LF Bands – Rulemaking Ruminations (Part 1)


John Davis of the Longwave Club of America has been doing a good job of keeping us informed of the present 2200/630m application status for U.S. amateurs. It seems that although the NPRM has not yet been published in the Federal Register, the FCC website is open for comments on this issue. I would urge all amateurs with an interest in LF operation to file comments that address the FCC's Notice Of Inquiry (NOI), particularly if you have been operating an experimental station. As well, Canadian LFers operating on either band should consider filing comments as well, describing your system and overall operating results. You can read a full review of the FCC's concerns in three of my earlier blogs:

http://ve7sl.blogspot.ca/2015/04/lf-mf-next-step-for-us-amateurs-part-1.html

http://ve7sl.blogspot.ca/2015/05/lf-mf-next-step-for-us-amateurs-part-2.html

http://ve7sl.blogspot.ca/2015/05/lf-mf-next-step-for-us-amateurs-part-3.html


John's latest information points out what he believes are three crucial points that deserve serious thought. As he indicates, if we don't 'get it right' the first time, it might be very difficult to make any changes after the fact. Please give serious thought to John's information and to filing your own comments at the link provided.

In John's own words:


Rulemaking Ruminations

This is probably a good time to get discussion reactivated on the MF and LF ham proposals. Although I continue not to see publication of the NPRM in the Federal Register as yet, the FCC EFCS Web page for the proceeding is open and accepting filings. Until FR publication, we won't know the closing dates for comments and replies, but you can see what's already been going on at:

http://apps.fcc.gov/ecfs/proceeding/view?name=15-99

While I've been awfully tied up with other things recently, my reading of
the proposal thus far brings to mind three points I believe we earnestly
need to address with the Commission. This proceeding will set the exact US
rules for 2200 m, and very probably also 630 m, so it behooves us to make
the best case we can, now, right up front. If the initial rules are too
restrictive on amateur activity, it could be very difficult and time
consuming to get them changed. Here are my present concerns.

* ONE: In paragraph 168, the FCC states that in addition to separation
distances and power limits, "we propose to limit amateur stations to
operations at fixed locations only to ensure that this separation distance
can be maintained reliably." That's stricter than it may first sound. The
FCC's actual proposed wording for § 97.303(g)(1), for both 2200 and 630 m,
is: "Amateur stations are restricted to use at permanent fixed locations."
Permanent fixed locations. That goes way beyond my suggestion that mobile operation be prohibited. It precludes temporary fixed operation, such as Field Day activities, or tests of ground characteristics for future potential antenna sites, or other legitimate short-term experiments. In my view, this is needlessly restrictive, and could also open the door to more rigid coordination requirements that might paint us into a corner, figuratively and literally, at our original QTHes.

We need to make a strong case that hams are able to identify electric
transmission lines and maintain 1 km separation (or other specified
distance) from them. This further relates to comments the FCC seeks in par. 176: "Amateur licensees will have to determine the location of transmission lines in their vicinity to determine if they are permitted to operate stations using these frequency bands. .... High voltage transmission lines are typically attached to large steel towers that are easy to identity.
However, lower voltage transmission lines are typically attached to wooden poles. Although the wooden poles used for transmission lines are usually taller than the wooden poles used for distribution lines, we recognize that distinguishing the two types may not always be straightforward. We seek comment on whether amateur licensees will be able to identify the transmission lines in their locality."

Obviously, just glancing around a proposed operating site and saying "nope, I don't see a transmission line" is not enough. But I think we're smart enough to do responsible surveys of all lines within a mile or so in all directions, identify any substation locations, and determine which sets of poles have customer connections (practically the definition of distribution lines) and which don't (therefore assumed to be transmission lines). We need to convince the FCC that we can tell the difference.

... to be cont'd

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