Irony

The FCC issued Report and Order 17-33 which creates two new bands for amateur radio, 472-479 kHz (630 meters) and 135.7-137.8 kHz (2,200 meters).  As ARRL reported, it is a “big win” for amateur radio.  I’ve been waiting in anticipation for the 630 meter band as it’s an old yet new frontier for us.  With old Sol taking a bit of a nap for the past few years and perhaps for years or decades to come, lower frequencies are where we’re going to have to play for more fun.

There are a few caveats in using these bands.  The FCC is requiring radio amateurs be at least 1 km from electric power transmission lines using Power Line Carrier (PLC) systems on those bands.  PLC is a technology that uses low frequency signals on power lines to perform signaling and control functions, and often meter reading.  Amateurs will have to notify the Utilities Technology Council (UTC) of station location prior to operating on 630 and 2200 meters.  The UTC maintains an industry database for PLC operations.

Those who were around to experience the Broadband over Powerline (BPL) brouhaha around 2003 to 2005 may recall the UTC organization.  At the time BPL was billed by proponents as the next big thing in broadband Internet.  Amateur radio operators and ARRL argued vigorously against BPL, citing engineering and evidence that the HF signals on the power lines radiated into the ether and interfered with HF radio operations.  The FCC turned a blind eye to the issue.  Luckily market forces took out BPL as a viable broadband solution due to increasing bandwidth needs and numerous failed trials which uncovered its technical difficulties and business problems.  PLC and BPL are cousins, with PLC operating below 500 khz and HF BPL operating from 1.8 to 30 Mhz.

The UTC, several electric utilities, and a handful of BPL equipment vendors at the time claimed that BPL didn’t interfere with HF radio operations.  The explanations and claims baffled those of us experienced in wireless and RF engineering as it’s a fact that an unshielded conductor tens of wavelengths long, conducting RF signals, will radiate energy.  The math and science supported this and measurements in the field provided real life evidence.

The UTC notes the following about PLC operation:

“This Activity is established as provided for in the FCC Rules and Regulations, Part 90.35(g) (47 C.F.R. ‘ 90.35(g)) relative to PLC operation in the 10-490 kHz band, and the NTIA Manual of Regulations and Procedures for Federal Radio Frequency Management, in Part 8.3, under the heading “Notifications in the Band 10-490 kHz,” (see 47 C.F.R., Chapter III). Electric utilities are allowed to use power line carrier (PLC) transmitters and receivers for control signals and information transmission in the 10-490 kHz band without obtaining a license from the [FCC]. However, PLC users are not protected from interference from licensed radio transmitters.”

Part 90.35(g) states that PLC operates under Part 15.  With the distance separation and notification requirement for amateurs, the FCC has granted an unlicensed incidental radiating non-wireless service protection from a licensed wireless service.  This was essentially the case with BPL in the early 2000s with an unworkable process for resolving interference issues, and interference complaints from amateurs living in trial site areas languishing for months with no action.

With this latest frequency allocation to amateur radio and requirements for protecting PLC operations, the tables are turned.  It’s the electric utility industry, that once claimed power lines wouldn’t interact with wireless spectrum, that could potentially experience interference.  Undoubtedly many FCC staffers involved in BPL in the past are no longer at the agency and the electric utility industry has forgotten about the BPL fiasco and fail to realize the irony of needing to protect PLC from wireless.

All this being said, I’m not attempting to downplay or criticize the allocation of the two new bands.  I think it’s wonderful and I applaud ARRL’s success.  However, I hope amateurs wishing to enjoy these bands aren’t prevented in doing so.  While it’s unlikely a large number of amateurs will be excluded from operating due to PLC on high voltage transmission lines, PLC systems are used in meter reading applications in neighborhood power distribution systems.  Hopefully the majority of systems do not operate in the new 630 and 2200 meter amateur bands and we can peacefully coexist, unlike what occurred with BPL.

Anthony, K3NG, is a regular contributor to AmateurRadio.com.

8 Responses to “Irony”

  • Roger G3XBM:

    As an “outsider” I cannot believe how S L O W the FCC has been. Most nations have had these bands for years now!! Even with a measured 5mW ERP on WSPR I have been copied over 1000km in all DX seasons on 472kHz. My best DX is just under 1800km. Most nights I hear this sort of range. All the FCC had to do was introduce a low ERP initially and demand closure of any station causing interference. FCC = Federal Crap Commission? Sorry for not being charitable, but the delays those in the USA have suffered are just inexcusable. Pen pushers who don’t care about amateurs as they generate no revenue?

  • Barron, AK1F:

    If I am interpreting this correctly, in my part of our state EVERYONE is within 1km of plc, and the new bands will not be available to any amateurs here.

  • I looked a little closer at the FCC R&O and found this footnote defining PLC:

    “WRC-12 NPRM, 30 FCC Rcd at 4240-48, paras. 159-182. PLC systems are defined as an unintentional radiator
    employed as a carrier current system used by an electric power utility entity on transmission lines for protective
    relaying, telemetry, etc. for general supervision of the power system. The system operates by the transmission of
    radio frequency energy by conduction over the electric power transmission lines of the system. The system does not
    include those electric lines which connect the distribution substation to the customer or house wiring. 47 CFR
    § 15.3(t).”

    So it would appear that the FCC isn’t including PLC operating in distribution lines and presumably for meter reading, as PLC for the purposes of this. So perhaps the 1 km limit won’t bite us with meter reading system, but it would be good for someone to confirm this.

  • walt n5eqy:

    There you have it, the citizens against the bureaucracy who have exercised the privilege of wealth, bribery, coercion and paid off politicians who prove once again that govt is nothing more than the political minority screwing the majority for $$$ and favors..

  • robert farey G6LLP:

    Hi guys
    so you have been given some frequencies in the LF bands well the best of luck. Now even uncle SAM has realised it takes excessive amounts of power to propagate radio waves at these frequencies which means a lot of expensive equipment to get a signal halfway around the world. Ground waves do travel great distances provided you have the resource of power. as we generally don’t have such resources it will be just a plaything. so the best of luck with your endeavours. Best Regards Robert.

  • Roger G3XBM:

    Robert – WRONG!!!! – big antennas and high power are NOT, repeat NOT, necessary on 472kHz. Re-read my comment please. Even my very low ERP QRSS3 signals on 137kHz have been received at decent distances. These are challenging bands but just a few mW ERP will get results. BTW, my little transverter for 472kHz (see QST last year) can be built for very little buying all parts new. A decent junk box will have most of the parts. So you do NOT need expensive gear, you do NOT need “excessive amounts of power”, and you do NOT need big antennas. All will get you further, but a lot of fun can be had with a very modest LF or MF set-up.

  • KK4ZU:

    It strikes me as folly to transmit control and monitoring data over power lines. Think about how easily that system can be hacked…
    Oh, well. I’m now really interested in learning more about the new band access. Sounds like fun!

  • A few follow up comments:

    Yes, the FCC has been very slow with allocating this band. It’s a bit embarrassing.

    Regarding PLC and security: It’s my understanding that there are several generations of PLC systems. Early ones, which I’m told are still in use, are very primitive with the mere presence of an unmodulated PLC signal triggering something to happen at the receiving end, like opening up a high voltage switch. With a sufficient signal level transmitted and caught by a transmission line, bad hombres could do bad things. Presumably later generation systems are more sophisticated and have digital modulation to carry data and provide a means of authentication and are much more secure.

    I’m now less concerned about PLC used in meter reading applications, looking the language I quoted above from the R&O.

    I’m rally looking forward to trying 630m.

Leave a Comment

Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter
News, Opinion, Giveaways & More!

E-mail 
Join over 7,000 subscribers!
We never share your e-mail address.



Also available via RSS feed, Twitter, and Facebook.


Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter

 
We never share your e-mail address.

Please support our generous sponsors who make AmateurRadio.com possible:

KB3IFH QSL Cards

Hip Ham Shirts

Georgia Copper

Ham-Cram
Expert Linears

morseDX

Ni4L Antennas

N3ZN Keys

West Mountain
R&L Electronics


Do you like to write?
Interesting project to share?
Helpful tips and ideas for other hams?

Submit an article and we will review it for publication on AmateurRadio.com!

Have a ham radio product or service?
Consider advertising on our site.

Are you a reporter covering ham radio?
Find ham radio experts for your story.

How to Set Up a Ham Radio Blog
Get started in less than 15 minutes!


  • Matt W1MST, Managing Editor




Sign up for our free
Amateur Radio Newsletter

Enter your e-mail address: