41-meter band in North America

Discussion on current conditions, the solar cycle, grayline reception, logs covering several continents etc.

41-meter band in North America

Postby Eric Weatherall » Sat Jul 22, 2006 2002 UTC

I ask this question every few months in other forums, but I admit I haven't yet heard the answer I'm really seeking.

Is there a technical reason for why 41-meter band reception would be poor in California? In some of their radio manuals, Grundig/Eton points out that 41-meter reception will be better on the east coast than on the west coast.

Possible causes for this:
* ionosphere conditions
* broadcasting practices / targeting
* broadcasting strength / station proximity
* myth!

I would love to hear any viewpoints on this subject. I'm in the San Francisco bay area and my primary interest in the 41-meter band is WBCQ in Monticello, Maine on 7415 khz (yes I know, 40.45853 meters :)
weatherall
shortwave weblog: http://cobaltpet.blogspot.com/
Eric Weatherall
Member
 
Posts: 28
Joined: Mon Jul 10, 2006 0355 UTC
Location: California, USA

Postby Glenn Hauser » Sat Jul 22, 2006 2327 UTC

WBCQ is a fairly long haul from the other side of the continent. It is aimed at Nuevo Laredo at 245 degrees, so is pretty far offbeam for you. I suspect but don`t know for sure it has a fairly hi take-off angle, which means better strength at the first hop, closer range to Maine. You might take a look at the VOACAP animated coverage maps on the WBCQ website, keeping in mind that that is just theoretical. http://www.wbcq.com/index.php?option=co ... &Itemid=48

Signals over a more northerly path are at a disadvantage due to auroral effects, and you can`t get a more northerly path in the conterminous US than from Monticello, Maine. In the summer, in addition, you are not getting a full darkness/night path. Also, WBCQ signs off weeknights (tho later on weekends) at 8:30 pm PST, altho it would have a better full night path for you if it stayed on later. 50 kW (nominal) for WBCQ also doesn`t match the 100 or 250 or even 500 kW so many other SW stations use, in the US and out. So you have several factors working against you for receiving that particular station well.

Grundig must have been referring to reception from Europe being better on the east coast on 7 MHz, but that also applies to other bands. This is not only due to proximity, but since the paths don`t have to penetrate the auroral zone, or not so much of it. Conversely, you should have better reception from Asia (in the mornings) on 7 MHz. Regards, Glenn Hauser
Glenn Hauser
Member
 
Posts: 94
Joined: Mon Aug 05, 2002 1542 UTC
Location: Enid OK USA

Postby Eric Weatherall » Sun Jul 30, 2006 1629 UTC

Glenn Hauser wrote:WBCQ is a fairly long haul from the other side of the continent. It is aimed at Nuevo Laredo at 245 degrees, so is pretty far offbeam for you.


Thanks Glenn. That was a truly excellent and useful response! I am pleased to learn about the broadcasting direction of WBCQ even though it means I am technically outside the lines. On weekdays it is hard for me to listen before 9PM local time (GMT-7 summer, GMT-8 winter).

Also I will go read more about the auroral zone that you mention. I was wondering if any broadcasts were directed over the north pole, e.g. maybe it would make sense for India if propagation allowed.

I'll look into morning reception in 41-meters sometime as well. Recently I have been picking out stations from the primetimeshortwave.com schedule, but I should spend more time scanning.
weatherall
shortwave weblog: http://cobaltpet.blogspot.com/
Eric Weatherall
Member
 
Posts: 28
Joined: Mon Jul 10, 2006 0355 UTC
Location: California, USA

Postby Glenn Hauser » Sun Jul 30, 2006 1945 UTC

Eric, I can`t think of any SW stations which deliberately broadcast across the north polar region. Altho signals sometimes get through when conditions are abnormal, often with ``auroral flutter``, it`s long been recognized that this is not a viable path. Some broadcasts from the Middle East or Eastern Europe come close for those of us in CNAm, and even more so for WNAm, but they are actually aimed around NW to NNW from the site rather than due N.

It`s probably one reason why All India Radio has never broadcast to North America (tho it could easily be done with relay stations, or the auroral zone problem could be reduced by using sites in extreme western India for eastern North America, and extreme eastern India for western North America.)

There are a number of broadcasts accidentally heading toward North America through the northern auroral zone, such as from the Sri Lanka sites, but they are intended only to reach close regions of Asia. The lamented Radio Tashkent, Uzbekistan, used to be heard with some regularity in North America during their 1200 or 1330 UT English broadcasts, but it was actually aimed the other way toward India.

Any broadcasts reaching you in California from the Iran-Afghanistan-Pakistan area, and countries north of them, would be more or less trans-polar, but none are actually aimed at you. Regards, Glenn Hauser
Glenn Hauser
Member
 
Posts: 94
Joined: Mon Aug 05, 2002 1542 UTC
Location: Enid OK USA


Return to Propagation

Who is online

Users browsing this forum: No registered users and 0 guests