Many horizontal MF BCB wires were in use, The old rooftop WBZ and later WBZA
site in Springfield MA on top of the old Westinghouse plant was razed only
last November. Some say it was an inverted L strung between those. My oldest
son lived 2 blocks from there until moving to NH in January this year.
http://www.necrat.us/wbza/wbza.html
The early WBZ antenna near Boston was a horizontal wire array on wood poles
with a counterpoise just above head level.
Purely horizontal would be what is now called NVIS unless the towers were
tall enough to have lower lobes.
There was a station in Lowell MA that had a tower on a 4 story building with
a metal roof and was operational not that many years ago. It always had a
strange sounding watery signal outside the city.
Many historic towers still exist and changing would be cost prohibitive or
are considered "historic sites" such as WSM.
WBT has 3 of the 8 still operational Blaw-Knox towers and two were rebuilt
after Hurricane Hugo. The others are WSM, WLW, WFEA (which I pass almost
daily), WBNS, and KSTN which is a scaled down version. Others were scrapped
or shortened.
Its interesting to note that the Blaw-Knox company claimed 70% of the tower
market in 1942 but the diamond design were very few as uniform cross section
became the norm.
Carl
KM1H
----- Original Message -----
From: "Bruce" <k1fz@myfairpoint.net>
To: <topband@contesting.com>
Sent: Monday, May 07, 2012 5:49 AM
Subject: Topband: Fw: Monopole Radiation Patterns, takeoff angles etc
>
>
>
> Early 1920's AM radio stations in Bangor Maine had horizontal roof top
> antennas. WLBZ, when it first moved from Dover Foxcroft to Bangor had only
> one program, a church service on Sunday morning. I have found no evidence
> of mountain top AM radio stations in the state. Much later they went to
> towers erected in moist fresh water areas. Even later some discovered
> near
> salt water sites were better.
>
>
> 1920's Low frequencies in Maine
> I have done many years of research on the Radio Corporation of America
> radio relay station 1XAO in Belfast Maine on air from 1923 to until the
> depression of 1929. They had four 150 foot towers. three in the form of a
> triangle with the 4th in the center. It was a horizontal affair with feed
> wires coming down near to each tower to tuning coils for different
> transmitting frequencies. The main frequency was 182 Kilocycles (1650
> meters)
> Receiving was by a wave antenna ( named Beverage later) that was two #10
> copper wires running parallel on cross arms spaced 64 inches with an
> average
> height of 18 feet. The wires were transposed at frequent intervals, and
> the
> length was 52,610 feet (just under 10 miles) As time went on from 1923 to
> 1926 they installed two more wave antennas. The finished array had three,
> the same length, and spaced 6 miles apart. Harold Beverage made trips to
> check installation progress. (Harold's boy hood home, and some family
> members lived on North Haven Island a short distance away.)
>
> Samuel Winthrop Dean, the Engineer in Charge of 1XAO, left RCA and went
> to
> Houlton Maine, December of 1925 to build the first Trans-Atlantic AT&T
> radio
> telephone. Dean graduated from Harvard and was a licensed amateur radio
> operator, call 1ZD issued by the Department of Commerce, radio service
> bulletin Feb 1915 No.2 special land station, wavelengths 200, 425, 600.
>>From his Harvard records he was a charter member of the ARRL. At Houlton
> Maine he installed a large complex (Beverage) wave antenna array. Patents
> are available through Google searches.
>
> 73
> Bruce-K1FZ
>
>
>
>
> ----- Original Message -----
> From: "W2XJ" <w2xj@nyc.rr.com>
> To: <topband@contesting.com>
> Sent: Sunday, May 06, 2012 8:20 PM
> Subject: Re: Topband: Monopole Radiation Patterns, takeoff angles etc
>
>
>
>> Having worked in the business over 54 years with LW MW and SW
>> transmission systems up to 2 megawatts and having built numerous MW
>> arrays to 12 towers I would respectfully suggest a quick check of
>> fundamental broadcast history. Google is your friend.
>>
>> BTW most early stations broadcast from rooftops, not mountain tops,
>> and some diamond towers (Blau Knox) are still in service at legendary
>> stations.
>>
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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_______________________________________________
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