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These links and files show the range of interference issues that have been and are being caused by BPL systems worldwide. Although some BPL manufacturers are avoiding these problems for Amateur Radio by taking the steps ARRL provided to the FCC during the BPL rulemaking proceeding, as can be seen in these videos, this is not being done by all BPL manufacturers in all systems. Even in systems that do notch Amateur Radio, interference on other spectrum is just as bad as what is seen here. This industry has a long way to go to achieve the relative compatibility that has been achieved by the cable and DSL industries.
The main things that differentiate BPL from other interference are:
1. Across a given ham or shortwave band, the interference will be continuous with frequency. Main.net modems will not sound any different as one tunes across the band. DS2-chipset-based BPL modems generate carriers every 1.1 kHz or so, and as one tunes the band in these systems, one will hear these carriers completely fill the band. With a receiver in the AM mode, a continuous 1.1 kHz tone will be heard. At this time, Ambient, Amperion and Corinex modems use DS2 chipsets.
2. The onset of BPL interference vs frequency will be rather abrupt, going from essentially no BPL noise to full BPL noise over the span of a few 10s of kHz. As one tunes through the BPL signal, it will remain constant, perhaps varying some over frequency based on the gain of the antenna used with the receiver. At some point as the receiver is tuned, it will disappear just as suddently as it started.
3. Most BPL systems have notches as mandated by Part 15 rules. These notches may be only 20 dB, so by ear, with receiver AGC, they may not be readily apparent by ear, but if the receiver S meter shows the signal dropping in the notches that are mandated by Part 15, that is also characteristic of BPL. In the US, most BPL manufacturers are notching the ham bands, so in that case, BPL noise would be strong above and below the ham bands, but may not be very strong within them. The notching is usually less effective at the band edges.
4. Main.net and DS2-based BPL systems are found with strong noise on HF and possibly into VHF. They use HF and VHF mixed for both the in-premise and access BPL on overhead and underground lines. The system makes noise on its downstream direction even when not in use, with dead carriers every 1.1. kHz. The upstream direction makes noise whenever data is flowing. When data is flowing, the modulation is evident on the downstream carriers. Current Technologies systems use HomePlug modems in premises. These operate from 4-28 MHz, but with fixed notches in the ham bands. On overhead and underground distribution lines, Current systems use 31-49 MHz.
BPL UNREDACTED: ARRL's Dave Sumner reviews redacted FCC info on BPL interference
ARRL CEO Dave Sumner K1ZZ reviews some of the "smoking gun" material that the FCC redacted from its public disclosure of staff and NTIA studies on the unwanted radio interference created by BPL.
Broadband over Power Line Video (19,068,932 bytes, MPG file)
This video clearly and concisely explains and depicts the threat of Broadband over Power Line (BPL) to Amateur Radio. The video, BPL and HF: A Primer, runs approximately three and one-half minutes (including credits). It's suitable for Amateur Radio club presentations as well as for non-ham audiences, such as the news media, civic clubs, local governments and emergency response agencies.
Audio interview with VK7HCK on BPL interference in Australia
8/22/2005, Wireless Institute of Australia -- VK7HCK offers an audio report on the initial deployment of the BPL trials in Australia. He reports and plays strong, continuous interference on HF.
NY PA TX VA
Mutli-city
Other countries
Video of BPL interference in Emmaus, PA (26,854 KB, MPG file)
This video shows BPL interference caused by generation-1 Main.net equipment in Emmaus, PA. It shows that the receive capability is significantly degraded within the BPL area in Emmaus, compared to areas outside the trial area. (Courtesy of Carl Stevenson, WK3C, Emmaus, PA.)
This BPL trial was shut down by PPL.
Video and Audio from the BPL installation in Austin, TX (March 26, 2007)
This page has links to audio and video documentation of recent interference to WWV and shortwave broadcasting from the Corinex BPL system being installed in Austin, TX.
This BPL trial was shut down by Austin Energy.
Recordings of BPL signals in Irving, TX
This page is a video recording of interference caused by the generation-1 Amperion BPL system in Irving, TX.
This BPL trial was shut down by TXU.
Video and Audio showing that "notching" in Manassas, VA has not been effective.
The truth about Broadband over Power Lines - BPL
This video shows the Main.net BPL system operating in Manassas, VA. Interference from the system is strong on the 40-meter (and other) Amateur bands. The video also shows the results that brief Amateur transmissions had on the system. BPL noise compared with the lack of noise outside the BPL area:
Audio file showing clear reception outside of Manassas
This recording shows a typical Amateur Radio communication as received by a station located outside the Manassas BPL trial. The recording was made on the 7-MHz Amateur Radio band on February 5, 2006.
Audio file showing same communication heard in the BPL area
This is a recording of the same conversation of a moderately strong station and a stronger station in communication with each other, made from within the Manassas Main.net BPL area. This is the spectrum that Main.net and COMTek claim does not have any "legitimate" interference.
Video showing interference in the notched spectrum in Manassas
Although this area has been "notched," the amount of notch filtering done by COMTek is inadequate to protect licensed radio users. This video shows the exact same communication as shown in the link above, but within the notched area of overhead wiring in Manassas.
Video showing interference over a wide geographical area
The above tests do not show a single "hot" area where emissions are particularly strong. This recording, made in the "underground" BPL area on February 5, 2006, shows that moderate to strong interference exists over the entire geographical area of the deployment.
Notching has not changed much from earlier attempts to resolve interference -- This audio of interference made last year in Manassas by the video of BPL interference from the BPL system in Manassas, VA was made by the Old Virginia Hams. Their tests also show a spectral display of BPL interference obstructing communications on the 40 meter Amateur band.
In response to claims by the BPL operator in Manassas, VA, Communications Technology, that they had corrected all interference problems in Manassas, local Amateurs in Manassas documented that this is not true with recent site testing in various parts of Manassas. This series of audio and video files show that the claim that all interference has been corrected in Manassas is not correct.
These audio recordings of BPL interference in the BPL system in Manassas, VA were made by the Old Virginia Hams:
WWV on 5 MHz
WWV on 10 MHz
WWV on 15 MHz
Forty-meter conversations:
Conversation 1
Conversation 2
This shows the strong interference levels to a mobile amateur receiver seen by ARRL technical staff in four BPL-test areas. It shows that the BPL signal completely occupies entire amateur bands and beyond. The mobile station used was driven around a large geographical area, showing that BPL interference is not just a local "hot-spot" phenomenon. It is useful to hear how BPL signals sound when the radio is tuned across the band. Test area #1 is the Current Technologies "HomePlug" system in Potomac, MD. Test area #2 is the Main.net system in Manassas, VA. Test Area #3 is another Main.net system operating in Emmaus, PA. Test area #4 is from the Ambient Corporation installation in Briarcliff Manor, NY.
o BPL and non BPL compared: Broadband (9 MB) Dialup (4.6 MB)
o Current Technologies system (Potomac, MD): Broadband (3.8 MB) Dialup (3.4 MB)
o Main.net system (Emmaus, PA): Broadband (22.2 MB) Dialup (2.6 MB)
o Ambient system (Briarcliff Manor): Broadband (4.2 MB)
Unspecified DS2-based system
Sample of BPL interference – recorded by Gary Pearce, KN4AQ
Video and audio recordings of BPL interference made in other countries
Australia
BPL - An Radio Amateur's Perspective - Nth Hobart
A radio amateur's virtual tour of the North Hobart BPL trail in Hobart, Tasmania, Australia. The BPL system is manufactured by Mitsubishi, using DS2 chipsets. As can be seen, this BPL system is operating un-notched in the Amateur bands and is causing widespread interference in an entire neighborhood. Amateur Radio and listening to shortwave broadcasts is not possible in this area on spectrum the BPL system is using.
Broadband over Powerlines - A Radio Amateur's Perspective
A radio amateur's tour of the Mt Nelson BPL trail in Hobart, Tasmania. Audio and video presentation of the interference potential of this technology.
Are You Ready for BPL in Your Neighborhood?
This is a video of the base station operations of VK7TW near the South Hobart BPL trial that was shot in October, 2007. The BPL system was un-notched in all bands and made by Corinex with DS2 chipsets.
First Aurora Trial (DS2 45Mbps OFDM) Kirksway Place. Courtesy of VK7TAS. (wav file)
Second Aurora Trial (DS2 200Mbps OFDM) Mt Nelson 80m. Courtesy of VK7HCK. (MP3 file)
Second Aurora Trial (DS2 200Mbps OFDM) Mt Nelson Normal Background Noise on 28.200MHz (10m band). Courtesy of VK7TW. (MP3 file) Second Aurora Trial (DS2 200Mbps OFDM) Mt Nelson 28.200MHz (10m band) in Trial area. Courtesy of VK7TW. (MP3 file)
Second Aurora Trial (DS2 200Mbps OFDM) Mt Nelson Tuning across the 15m band. Courtesy of VK7TW. (MP3 file)
Second Aurora Trial (DS2 200Mbps OFDM) Mt Nelson Tuning across the 20m band. Courtesy of VK7TW. (MP3 file)
Second Aurora Trial (DS2 200Mbps OFDM) Tolmans Hill 21.100MHz (15m band). Courtesy of VK7TW. (MP3 file)
Powerline Signalling The Death of HF Radio
This 2009 video shows interference from a single in-premise device located in a neighboring home. The ham bands are notched, but not perfectly.
BPL interference to shortwave broadcast in the UK
BBC video showing BPL/PLC interference
This video shows strong interference to international shortwave broadcasts from a single in-premise BPL installation.
Audio and Video Recordings of PLC/BPL interference in Austria:
http://www.powerline-plc.info/downloads_en.html
BPL Testing in Statzing, Austria
BPL interference to digital shortwave broadcasting:
Demos of PLT impact on the HF Broadcasting services can be seen and heard on: http://www.ebu.ch/en/technical/publications/userguides/index.php .The demo called "The digital Haze" is a presentation including an audiovisual demonstration of the interference. Download the zip file and keep all files in the same folder after unzip. Run the demo in slide show mode with Power point.
BPL/PLC News Article on Swiss Television
July 15, 2005, HB Time -- This newcast was broadcast in French on Swiss television. It states that PLC In Europe is losing momentum and showing its limitations. Leaks causing disruption to shortwave reception are most noticeable within a neighborhood of 10m from the PLC adapter. It also seems less of a priority than existing radio services. The regulators, OFCOM, still want to give it a chance since the field of telecommunication can evolve quickly. SIGE, an electric utility in Geneva, Switzerland claims a "lack of closure" after testing it. A hospital might have liked PLC due to its simplicity and low cost . The piece shows a brief clip of very strong interference to shortwave reception from BPL.
Videos showing interference in the BPL system installed in Tuam in Ireland
Muliple files .AVI format. The BPL vendor is ESB. The 1.1 kHz spacing almost certainly indicates a DS2 modem chipset is being used. The system may not be operational at this time, but during its brief use, the interference levels were typical of BPL.
Video Showing Effect of PLC on Over-the-Air Reception In Fulmpes, Austria (2,632 KB .WMV file)
This video with sound shows the strong levels of interference experienced to an HF receiver brought to Fulmpes, Tirol, Austria during PLC field trials (OeVSV, Austrian Amateur Radio Society)
Video Showing Effect of PLC in Linz, Austria (4,823 KB .RM file)
This video with sound shows the strong levels of interference experienced to an HF receiver brought to Linz, Austria during PLC field trials (OeVSV, Austrian Amateur Radio Society)
Video Showing Effect of PLC in Tirol, Austria (1,168 KB .RM file)
This video with sound shows the strong levels of interference experienced to an HF receiver brought to Tirol, Austria during PLC field trials.(OeVSV, Austrian Amateur Radio Society)
DS2 in premise modem testing in Austria
In these tests, a DS2 modem was tested in an apartment in Austria. These modems operate from 2-32 MHz, with programmable notches. They are multi-carrier OFDM systems operating at a power level of -56 dBm/Hz.
The following files are provided courtesy of the Radio Society of Great Britain:
PLT Test Information Including Sound Bites
Internet: http://www.qsl.net/rsgb_emc/PLTREP.pdf
Summary: This report summarizes field tests of PLC made by the Radio Society of Great Britain. As already reported elsewhere, it is difficult or almost impossible to capture and present the emissions from new broadband-communication systems using spread-spectrum-technologies at low or unknown data-rates (stand-by) by simple use of a spectrum analyser. Nevertheless even at these very low data rates, the harmful effect of these emissions on radio systems all over the spectrum used for radio communication is at once evident, as soon as emissions exceed the conventional limits.
Author: RSGB The Mainnet system
Internet: http://www.qsl.net/rsgb_emc/MN_1.wav
Summary: Recorded about 3m from the house on the 7MHz amateur band. This is described as a spread spectrum system. Interference depends on the density of traffic. Recording starts with light traffic increasing as the recording proceeds.
Author: RSGB
The Ascom system #1
Internet: http://www.qsl.net/rsgb_emc/delivery.wav
Summary: Recorded about 4m from the house in one of the "delivery" frequency bands. This system uses three discrete frequency bands, below 10MHz, to deliver signals to the house. The bands are about 1MHz wide.
Author: RSGB
The Ascom system #2
Internet: http://www.qsl.net/rsgb_emc/inhouse.wav
Summary: Recorded about 4m from the house, in one of the "in-house frequency" bands. This system uses three discrete frequency bands above 10MHz to distribute signals in the house.
Author: RSGB
The following files are provided courtesy of DARC:
A PLC Audio Signal
Internet: http://www.darc.de/referate/emv/iaru/eurocom/plc.ra
Summary: A PLC audio signal.
Author: DARC
More BPL/PLC Audio Examples From Germany
These links were provided by Mike , OE3MZC, OeVSV
http://www.oe3mzc.oevsv.at/powerline/
http://www.powerline-plc.info/index_en.html
http://www.powerline-plc.info/downloads_en.html
BPL modem testing in Belgium
7MHz SSB, PLC starting up over a QSO. (100 kB MP3 file)
Sound of PLC in AM (on 21 MHz). (53 kB MP3 file)
Sound of PLC in SSB (on 28 MHz). (27 kB MP3 file)
Sound of PLC in SSB (on 7 MHz). (37 kB MP3 file)
Sound of PLC in SSB (on 14 MHz). (27 kB MP3 file)
More sound of PLC in SSB (on 28 MHz). (31 kB MP3 file)
The sounds found on this link are provided courtesy of the Japan Amateur Radio League (JARL):
They are digests of official recorded data for The Power Line Communication Study Group, Ministry of Public Management, Home Affairs, Posts and Telecommunications. These files are located on JARL Web. For detail of JARL measurement configurations, see the above presentation materials.
PLC in Japan
This web page features a number of audio recordings of BPL interference from in-premise BPL modems in Japan. Most dramatic are some of the demonstrations of strong interference to international shortwave broadcasting. The site also includes an excellent tutorial on BPL/PLC in Japan, as well as some spectral meaurements.
PLC Public Demonstration
http://www.youtube.com/watch?v=Eu7Wptlx5U8
This video from Japan shows the strong noise generated by in-premise BPL systems. To quote the presenter: “Please listen to the terrible noise! “ Information in Japanese about how these files were prepared is found at http://www.jarl.or.jp/Japanese/2_Joho/2-7_plc/H1902-jikken.htm.
PLC for HF BCL bands 1
http://www.youtube.com/watch?v=T6gieL7DpMk
PLC noise heard on the HF (short wave) radio boadcast bands with a whip antenna inside of the house. Narrated in Japanese.
PLC test for HF bands 1
http://www.youtube.com/watch?v=MmMBEM7zSxw
In this Japanese-language narrated video, you can hear the noise on the broadcast bands, but nothing is heard on the ham radio bands, because the Matsushita PLC modem has a kind of filter systems for the ham radio bands.
PLC for HF BCL bands 2
http://www.youtube.com/watch?v=6m82LjXRh0Q
You can hear the noise of PLC on the short wave radio broadcast bands.
PLC in Japan 1
http://www.youtube.com/watch?v=NuD92VYPSM4
This video shows more demonstration of interference from in-premise BPL in Japan. Narrated in Japanese.
PLC in Japan 2
http://www.youtube.com/watch?v=VmbgCTVybSM
This video shows more demonstration of interference from in-premise BPL in Japan. Narrated in Japanese.
PLC in Japan 3
http://www.youtube.com/watch?v=PfupBSJ-9mc
This video shows more demonstration of interference from in-premise BPL in Japan. Narrated in Japanese.
PLC in Japan 4
http://www.youtube.com/watch?v=IAECT9nICaA
This video shows more demonstration of interference from in-premise BPL in Japan. Narrated in Japanese.
PLC in Japan 5
http://www.youtube.com/watch?v=Zla4dTruZow
PLC in Japan 6
http://www.youtube.com/watch?v=7Nq8ykYA-2U
PLC in Japan
http://www.youtube.com/watch?v=Mxh9lIril70
CNC1000 PLC modem in Japan
http://www.youtube.com/watch?v=xNViZzcysoE
The noise of CNC1000 PLC Modem blocks Radio Nikkei.
PLC Noise shortwave radio
http://www.youtube.com/watch?v=MzHy8oFb5as
This video, narrated in Japanese, shows interference to shortwave broadcast from in-premise BPL in Japan.
PLC Test No. 1
http://www.youtube.com/watch?v=VTeJhi8i1WI
This shows the results of PLC on 14 MHz.
PLC Test No. 3
http://www.youtube.com/watch?v=pb8RsZX7qzg
14 MHz, FT-401(s)
PLC Test No. 2
http://www.youtube.com/watch?v=Zq8eVbY19_4
14 MHz, noise blanker off
Testing one, two, three...
The interference potential of this technology is very bad for Amateur Radio operators and HF communications all over the world.
Shortwave Audio
Shortwave Audio
