[ota_canuck]

Wind-Turbine flutter, blade reflections and multipath concerns!

Jase88,

Local Wind Turbines? Yes!, But I don't believe I am close enough to be concerned, unless the blades can somehow cause significant signal reflection pulses that could result in flutter or multipath issues.

These Dunnville turbine farms are about 1 mile southwest into the Port Maitland area near the Erie shores and there are some more turbines about 4miles southeast in Lowbanks near the Erie shoreline. My target markets are approximately 210° west, 80° east and 30° north, so I am not recieving any signals that would pass directly through those turbine props.

They have all been on the hydro-one grid for about 1 year now.

 

[Jase88]

Were you using OTA prior to these turbines coming online? And if so, did you notice any difference in reception?!

 

[majortom]

There are wind turbines on this side of Lake Erie also, just so ya know....

 

[ota_canuck]

Wind turbines are signal killers.

I've been OTA since 1990! Ever since the cable company's negative billing days.

I have never noticed any reception changes since the turbines came to town , my before vs after reception results were insignificantly changed.

Over the past 4 years, I have watched these big turbines being trucked in, raised and go online.

I installed a converter box in a house down in Lowbanks a year ago, and it was a multipath, fluttering disaster. His house was about 300 yards from these 6 swirling monsters that were wide spread over a farmers field. He then went with satellite because there is no cable available in that area, and that was also a pixelating/signal dropout nightmare, but everyone of any authority will instantly dispute the suggestion that it has something to do with these Wind Turbines.

In Port Maitland, one of my clients, [a lawyer] had satellite for several years, and suddenly when all of these turbines went into service, his internet & TV reception went for a crap. The authorities again said the Turbines were not to be blamed. His Sat-Provider then told him it was because the trees had grown taller and then they sold him a friggin 40ft free standing tower. He still has the same problems, except he is now the proud owner of a free standing 40ft tower.
Yes, he is taking legal action against the BDU and against the AIM Power Gen Corporation.

There are further provincially approved plans for the construction of 176 turbines extending north to Highway 3 from Nanticoke east to Port Maitland. Haldimand county was not consulted by the province. Haldimand County is also considering taking legal action against the province [McGuinty liberals] to try and stop this secretly contracted multi-billion dollar Samsung deal.

So, to make a long story short,... if your close enough, these wind turbines are signal killers.
________________________
This is off topic, but worthy of a thread regarding any known radio spectrum signal interferences.

 

[Jase88]

Thanks for the responses. Definitely something that relates to the reception of signals within the area where you reside. And in that context, germane to this thread (IMO).

After hearing about your issues with CHCH and other stations, I got to thinking about the wind turbines around the lake. Good to see that they don't appear to be killing anything for you...

 

[HDTV101]

http://www.youtube.com/watch?v=CEersoJLtRw

They do kill birds

 

[frisbeepilot]

Yes, wind turbines kill a few birds. But tall office and condo towers (especially those with lights left on all night) kill tons of birds, and nobody seems to mind when they go up.

I can see how metal turbine blades would affect electromagnetic waves; so would any tall metal structure, for that matter. (It's one of the reasons why CBC Radio 1 moved from AM to FM in Toronto; the longer AM wavelengths produced huge "dead spots" of destructive interference in downtown TO, and FM produces much smaller ones.)

Maybe I'm just a tree-hugging nut-job, but I'd much rather have wind turbines and (relatively) clean energy with a few people's TV reception inconvenienced, as opposed to more pollution and greenhouse gases in everybody's atmosphere. Then again... if you're one of The Inconvenienced, this is a pretty frosty comfort.

 

[HDTV101]

I would believe that this type of interference, you're experiencing from the wind farm, would be similar if not the same 'signal scatter' that is cause when an aircraft passes overhead causing a second signal path with a phase delay.

Using multiple stacked antennas can help solve this problem....

Thread about 'Airplane Flutter'
http://www.digitalhome.ca/forum/showthread.php?t=103432

My answer to 'Airplane Flutter' problem
http://www.digitalhome.ca/forum/showpost.php?p=962332&postcount=14

Document about 'Airplane Flutter'
http://2003.iccas.org/Full_Paper/airp_ICCAS2003_5(19).pdf


DAT-75 antenna

 

[c-sat]

I had been trying to figure out what happened to my reception for Detroit channels in the past few years - and was told by the local antenna installer, it was wind turbines. We live right by Lake Erie, near Rondeau Park. Cleveland and London stations come in well, and even Toledo and Erie are often better than Detroit stations. The installer mentioned that the when the wind is still or blows from the south (ie the blades are parallel to a line between us and Detroit), reception is OK.

So - in the past few years since this issue has become apparent, has anyone tried anyway of getting around the issue? If the issue is due to reflections off the blades, would having a super-directional antenna - such as the the ganged CM4228 approach in http://www.hdtvprimer.com/ANtennas/16bay.html work better? Or is there nothing that can handle the myriad of reflected signals.

 

[mrmemario]

I can't speak to the ganged CM4228, however I have tried the CM 4250, a CM 3671 and a DBGH to pick up City TV (out of Paris, Ontario) to no avail. 9 turbines were setup 1 1/2yrs ago across the road from me, disturbing my signal. According to my tvfool I should be able to pick it up easily, however I am only able to get a scattered picture on good nights. http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=e1c66460946520

I don't know if this helps, but this has been my experience.

 

[abnutcracker]

I can say the blades turning cause the problem for a a fact ..We had a local installer have the same issue with Detroit content for a windmill in the line of sight to the towers.As he explained when the turbines were stopped the problems with reception went away with everything working fine and came back when the turbines returned to rotating . In that installation it was a CM5020 being used.

 

[ExDilbert]

More antenna height should help. How much is difficult to say. It would have to be at least high enough to clear the wind turbines to get LOS to the TV towers. Even then, a very directional antenna might required. Stacking antennas, vertically and/or horizontally may also help. That is often used to reduce signal fluctuations due to other interference, like aircraft and tropo.

 

[mrmemario]

ExDilbert, these turbines are roughly 150-200 feet tall, getting above them would be out of the question. I know there are some "smaller" ones, but nothing under 100ft.

 

[ExDilbert]

That's a tough situation. I lose 1 and 2 edge signals here when helicopters fly over. (We are on a medical helicopter flight path.) Height may still help if it provides LOS to the TV towers. Without LOS, signals reflected off the wind turbines can be stronger than the main signal. Stacking and ganging antennas will work better with LOS as well.

 

[c-sat]

Problem with adding height is that we are right beside Lake Erie - ie the lowest point of land. There are hundreds of turbines between here and Detroit - all at a considerably higher elevation. No way that I can get above them. The local antenna installer has said that he has tried an 80' tower - but no success.

 

[Goombahz]

Hey all,

We're looking at renewing our antenna to eliminate a loss of signal. I came across this thread and it made me realize we may have the same problem. What we have noticed is on rainy weather days the signal is good and on sunny days we suffer from signal loss. My wife would say it's the wind but no on sunny windless days we lose signal. Can anyone else confirm/negate this possibility?

The cottage is at Lambton shores and our signal losses occur on channels 8, 10, 20, 29, 42 and 51 which is where the new wind farm has erected along the east coat of lake Huron. We were at the cottage last weekend high winds, rain and great reception yet the beach was ripped away, hummmm!!!

 

[ProjectSHO89]

What we have noticed is on rainy weather days the signal is good and on sunny days we suffer from signal loss.

You should probably investigate anything with a solar panel or solar cell that recharges a battery (ie, accent or security lighting) instead of tacking your post onto a thread that discussed wind turbines which, obviously, are not going to operate differently under the conditions you noted.

 

[ExDilbert]

It's more likely tropo interference from stations in Michigan. A better antenna could help.

 

[holl_ands]

Although Attenuation due to RAIN is not a problem at TV Frequencies, the WEATHER itself can have some profound impacts on Propagation, changing the Surface Conductivity as well as the Atmospheric Refractivity as the storm passes through....and then there are DUCTING effects that can HELP long range propagation....or KILL long range reception as the Duct PREVENTS reception, depending on relative heights of the Transmitter, Duct and Receiver.....esp. if the Transmitter is ABOVE the Duct:
http://www.pac-attack.com/articles/radio-wave-propagation
http://www.dxfm.com/content/propagation.htm

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FYI: Communications Research Center (CRC in Canada) published "Effects of Windmills on DTV" in Jan 2006 but I can no longer locate a weblink for this ATSC Study. However, it's probably similar to fol. Joint CRC and Univ. Basque Country, Spain Report. Since Interference appears as Multipath, try increasing Antenna Gain:
Impact analysis of wind farms on telecommunication services

Fol. article specifically addresses impact of Windmills on European (et. al. ) DVB-T Wavform:
http://www.ehu.eus/tsr_radio/images/International_Journals/ANGU-12-01.pdf

Fol. article also addresses diffraction from the Python Support Structures [May need FREE Registration to access]:
https://www.researchgate.net/publication/2378284_TV_Interference_from_Wind_Turbines

=====================================
BTW: See Audubon Society's summary of impact of Windturbines on Birds....and the lengths to which SOME [certainly NOT all] Wind Farms have gone to MINIMIZE these impacts:
http://www.audubon.org/news/will-wind-turbines-ever-be-safe-birds

And also fol. summary from [UK's] Carbon Brief....which compares bird deaths due to Wind turbines to the other, MUCH HIGHER causes of bird deaths:
https://www.carbonbrief.org/bird-death-and-wind-turbines-a-look-at-the-evidence
https://www.carbonbrief.org/about-us

 

[Goombahz]

Thanks for the responses, onward with the antenna....