Re: Topband: and KDKA
On 9/12/2013 11:48 PM, Jim Brown wrote: On 9/12/2013 4:06 PM, Herb Schoenbohm wrote: the nation's station which was WLW for sure Another interesting point -- WLW was a 50kW clear channel station, and one of a handful that had their frequency to themselves at night for all of North America, which is why the Commission might have considered licensing them for 500kW. As I recall, the other might have been WOAI, on 1200 kHz. 73, Jim K9YC _ Topband Reflector Hi Jim: For Years I have believed that WSM, 650, was in that category. Goodness knows, We can't miss the GRAND OLE OPRY 73, Mike, W5UC _ Topband Reflector
Re: Topband: and KDKA
In the 60's I used to do a jazz show on on a 1570 Khz radio daytimer station in Golden Valley, MN which is now KYCR. I remember a station which claimed to be in Del Rio, Texas but actually had a super high power AM station located across the border in Mexico.. I think the call sign was XERF but the studios were located in Del Rio which was later claimed to be a illegal cross boarder operation by the FCC. The frequency 1570 was listed as a Mexico Clear Channel which had an awesome skip signal that would just before sunset wipe out the show I was doing in as close as 5 miles away. I think this was also the station used by the infamous Dr. Brinkley to sell snake oil in the 30's and also the home of Wolfman Jack...I posted a piece from Wiki on this In the 1930s in Villa Acuña https://en.wikipedia.org/wiki/Villa_Acu%C3%B1a, now Ciudad Acuña, the border blaster https://en.wikipedia.org/wiki/Border_blaster XERF-AM https://en.wikipedia.org/wiki/XERF-AM made its home. The radio station was built by Dr. John R. Brinkley https://en.wikipedia.org/wiki/John_R._Brinkley from Kansas. Dr. Brinkley claimed to be able to cure male virility deficiency with goat gland transplants. Dr. Brinkley wanted to promote his male enhancement operations and used the radio station for that purpose. Because of the purpose of radio XER and what it promoted the station was closed in 1939 by the Mexican government. In 1947 the government of Mexico licensed XER-AM https://en.wikipedia.org/wiki/XER-AM, the super-power border blaster https://en.wikipedia.org/wiki/Border_blaster run by Ramon D. Bosquez on 100 kW. They used the old XERA facilities and sold its airtime to American Evangelists broadcasting in English to the United States https://en.wikipedia.org/wiki/United_States. In 1959, Ramon D. Bosquez and Arturo Gonzalez formed the Inter-American Radio Advertising, Inc. in Del Rio https://en.wikipedia.org/wiki/Del_Rio,_Texas, Texas https://en.wikipedia.org/wiki/Texas. They ran the broadcasting in Del Rio while the license rested in the hands of Mexican officials. They boosted the power to 250 kW. This super station was where famous disc jockey Wolfman Jack https://en.wikipedia.org/wiki/Wolfman_Jack between 1962 and 1964 became known. XERF-AM is currently under control of the Instituto Mexicano de la Radio https://en.wikipedia.org/wiki/Instituto_Mexicano_de_la_Radio and plays Spanish-language programs and music. Any corrections on what I remember about XERF would be appreciated. I also remember some old timers in Europe would listen on 1570 to see if the propagation on topband would permit contacts to the Midwest. Herb Schoenbohm, KV4FZ On 9/15/2013 9:13 AM, Mike(W5UC) Kathy (K5MWH) wrote: On 9/12/2013 11:48 PM, Jim Brown wrote: On 9/12/2013 4:06 PM, Herb Schoenbohm wrote: the nation's station which was WLW for sure Another interesting point -- WLW was a 50kW clear channel station, and one of a handful that had their frequency to themselves at night for all of North America, which is why the Commission might have considered licensing them for 500kW. As I recall, the other might have been WOAI, on 1200 kHz. 73, Jim K9YC _ Topband Reflector Hi Jim: For Years I have believed that WSM, 650, was in that category. Goodness knows, We can't miss the GRAND OLE OPRY 73, Mike, W5UC _ Topband Reflector _ Topband Reflector
Re: Topband: and KDKA
WLW shared the frequency with other stations, I believe one in Canada. I'm pretty sure that is why they had to use a directional pattern at night. Throughout a long history, WLW shared (and time shared) channels. The tower is a diamond shaped half wave, which makes it electrically shorter than a half wave. Another interesting point -- WLW was a 50kW clear channel station, and one of a handful that had their frequency to themselves at night for all of North America, which is why the Commission might have considered licensing them for 500kW. As I recall, the other might have been WOAI, on 1200 kHz. 73, Jim K9YC _ Topband Reflector Hi Jim: For Years I have believed that WSM, 650, was in that category. Goodness knows, We can't miss the GRAND OLE OPRY 73, Mike, W5UC _ Topband Reflector
Re: Topband: More anecdotal stories to cause one to stop and....
The radiated field of a vertical monopole present on the surface of lossy earth decays at greater than a 1/R rate. But, for example, the field shown at a horizontal distance of 0.1 km in my surface wave plot for an elevation angle of 5 degrees is not located on the surface of the earth. It is about 9 meters above it, and in fact, is a space wave. I'm not sure what plot you are referring to. Was this for a wavelength of something like 160m? I don't see how field values at a 100m (0.625 lambda) range and 9m (0.05625 lambda) altitude can tell us anything about the far-field behavior. Based on the documentation I've found, the basic NEC model treats the radiated field as a combination of the direct (free-space) wave and the part reflected from the interface, for which it uses an approximation. I assume that any part of the solution not included in these two is called the surface wave. It does not, by definition, contribute to the radiated (i.e. 1/r) field. Am I misunderstanding their (and your) definition of the surface wave? -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Richard Fry Sent: Friday, September 13, 2013 06:44 To: topband@contesting.com Subject: Re: Topband: More anecdotal stories to cause one to stop and Jack WS3N wrote: Then it would seem that what you call the surface wave must be the remaining part of the complete solution, and so it must decay exponentially in the vertical direction. ... a decaying solution can't be projected in a straight line and assumed to reach the ionosphere. The radiated field of a vertical monopole present on the surface of lossy earth decays at greater than a 1/R rate. But, for example, the field shown at a horizontal distance of 0.1 km in my surface wave plot for an elevation angle of 5 degrees is not located on the surface of the earth. It is about 9 meters above it, and in fact, is a space wave. Space waves DO decay at a 1/R (non-exponential) rate until they reach the ionosphere. Here is a link to a clip from Radio Engineers' Handbook by F.E. Terman (1st Edition), showing that the greatest single-hop range for radiation from a 1/4-wave monopole leaves the monopole at elevation angles below 5 degrees. The reduction in skywave field intensity seen in this clip beyond 150 miles downrange is due to the 1/R losses of those longer paths. http://s20.postimg.org/g3yy1uust/Terman_Fig55.jpg _ Topband Reflector _ Topband Reflector
Re: Topband: More anecdotal stories to cause one to stop and....
Go to this link: http://www.scribd.com/doc/23847007/Radio-Engineers-Handbook-1943-Terman ...and then type page 686 at the box in the toolbar just above the page display. It takes you to page 674 in the book. 73, Tony K4QE On Sun, Sep 15, 2013 at 5:18 PM, Richard Fry r...@adams.net wrote: AJ4SQ wrote: ... I'm only trying to understand what the model is doing, and what it means by surface wave. Chapter 10 of RADIO ENGINEERS' HANDBOOK (1st Edition) by F. E. Terman has a good discussion of this beginning on page 674, but the page count on the subject is too much to link to here. Hope those interested can access it, somehow. _ Topband Reflector _ Topband Reflector
Re: Topband: and KDKA
On 9/15/2013 13 13, Mike(W5UC) Kathy (K5MWH) wrote: Hi Jim: For Years I have believed that WSM, 650, was in that category. Goodness knows, We can't miss the GRAND OLE OPRY 73, Mike, W5UC Regarding these stations, Wikipedia is your friend: http://en.wikipedia.org/wiki/Clear-channel_station - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3408 / Virus Database: 3222/6667 - Release Date: 09/15/13 _ Topband Reflector
