January 1954 Radio-Electronics
[Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
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Sporadic E
propagation has been a significant source for long-distance (DX) radio signal
communications for voice, and Morse code (CW) for as long as radio has been
around, with digital data having joined the activity sometime around the 1970s.
Many contests are organized around the phenomenon where the regions of the
ionosphere's E-layer are to some extent randomly (as "sporadic" suggests)
ionized by solar electron ejections in a manner that renders it highly
conductive to certain wavelengths - primarily
VHF (30-300 MHz).
VHF is typically a line-of-sight transmission path. Via one or
more jumps, signals can travel very long distances, even half-way around the
world. Just as radio listeners considered it a challenge to pick up broadcasts
from far away, so, too, did some television watchers. I know a couple guys who
in the 1960s and 1970s engaged in the TV DX sport. One says he could sometimes
pick up, say, Miami, Florida from his home in Madison, Wisconsin. Another living
as a kid in Bangor, Maine, claims to have picked up TV stations in Puerto Rico.
This 1954 Radio-Electronics contains many instances of reports from
avid TV DXers who kept detailed records of their experiences.
TV DX in 1953 - Hardly a day went by without remarkable DX
reports.
Another great year for DX hounds and students
of propagation. Hardly a day went by without remarkable DX reports.
By E. P. Tilton, W1DQ, v.h.f. Editor, QST
Despite all that's been written on the subject and the fact that hams have been
working similar kinds of v.h.f, DX for nearly 20 years, it is still a source of
amazement to most TV owners to discover that reception is possible over distances
of more than 150 miles or so. Probably not one percent of all home viewers have
seen any TV DX. Yet in 1953 sporadic-E TV DX was received in the United States on
considerably more than one-third of the days; 133, to be exact. If we add all forms
of DX, we find that hardly a day passed in 1953 without someone pulling in TV reception
over distances that may seem incredible to the average viewer.
The nearly 150 people listed at the end of this article took the trouble to record
their observations and send them in to Radio-Electronics. They are all ages, of
both sexes, and from varied walks of life; schoolboys of 14 or 15, invalids bedridden
or confined to wheelchairs, TV service technicians, doctors, housewives. Quite a
few are hams, and all seem to share that special blend of curiosity and enthusiasm
that has made radio the fine hobby that it has been through the years.
Fig. 1 - Sporadic-E DX, report for 1953.
Causes of TV DX
Probably the most intriguing cause of TV DX is sporadic ionization of the E region
of the ionosphere, roughly 50 miles above the earth's surface, Normally v.h.f. waves
go off into space, but at largely unpredictable times this region bends them back
to earth at distances from 600 to 1,200 miles or so from where they started. They
may come in as close as 300 miles on rare occasions, and multiple-hop propagation
has been known to bring in stations as much as 2,500 miles distant. Sporadic-E
DX
is most common in May, June, and July, with a shorter period around Christmas time,
but it can happen anytime.
More common is extended-range propagation associated with easily observable weather
effects. Tropospheric DX can often be anticipated several hours to a day or two
in advance. It is usually at its best just before a general rain, and is almost
always associated with the middle or trailing edges of well-defined high-pressure
areas. Tropospheric DX is most common in the warm months, reaching its peak in September
and October.
Many other natural phenomena affect TV reception to some degree, The aurora borealis,
meteors hurtling through space, high-flying planes, and various forms of scattering
may cause weak signals to appear occasionally. All these are minor sources of TV
DX. Except for aurora they can be neglected, and even the northern lights are seldom
responsible for anything approaching entertainment quality reception.
Nature of sporadic-E DX
The seasonal character of Es (sporadic-E) DX is shown clearly
In Fig. 1. (November and December figures were taken from 1952 records.) The upper
columns show the number of days in each month when DX was logged; the lower ones
give the number of individual observations each month. The cycles for 19511
and 19522 were similar, but by no means identical. In 1951, May produced
the largest number of reports, with June a close second. In 1952, June topped the
list by a wide margin, with July second. This year we find July in the top spot,
with August well ahead of previous years.
That frequency is a dominant factor in Es DX is shown in Fig. 2. This
shows the percentage of the total number of stations in each channel plotted against
the percentage of the reports for that channel. It agrees well with previous years.
Nearly half the DX was recorded by channel 2 stations, though only 20% of the low-band
stations are in that channel. Channel 3 report and station columns are about equal.
In channel 4, most populated of all, 34% of the stations yielded but 29% of the
reports. Channels 5 and 6 together have one-third of the stations, but they account
for a bare 13% of the DX.
Geographical situation of the station is important. Those receivable in all directions
naturally outclass stations on either coast, but stations in lower latitudes enjoy
another advantage: DX occurs much more often below the Mason-Dixon Line. Note the
predominance of uban, Mexican, and Southern stations in the reports on Page 71.
Fig. 2 - Showing how the TV DX is divided among the low-band
v.h.f. channels.
A new champion!
For the first time since these reports have been collected, KPRC-TV, Houston,
Texas, has been pushed out of first place. In 1953, KFEL-TV, Denver, Colo., nosed
out the Houston station, 129 reports to 114. These two stations accounted for more
than a third of all the channel 2 reports, and KFEL's total is nearly 10% of all
DX reported. Looks like Denver should be a good place for 50-mc ham work!
KMTV, Omaha, WKY-TV, Oklahoma City, KRLD-TV, Dallas, WBAP-TV; Fort Worth, and
all the Cuban stations piled up impressive totals. A newcomer to the upper brackets
was WCBS, New York, with nearly three times their 1952 score. Could it be that new
Empire State Building antenna?
Tropospheric DX reports were received in great quantities in 1953. They show
that the higher ERP's now being employed by many stations are having a considerable
effect on coverage. They also reflect the recent improvements in receiver and antenna
design. Particularly in the south, viewers are reporting reliable reception over
distances in excess of 200 miles in a large number of instances.
Outstanding observers
The work being done by the more serious observers is most impressive, and the
number of both reports and observers is well up over previous years. To record details
of all would take most of this issue, but the work cited below is typical. Not a
little of it is being done in areas where there is no local service at all. Some
make a hobby of photographing DX for evidence, but such evidence is not always accepted
as valid. Observer Penc, Utica, N. Y., says one fellow he showed his pictures to
accused him of traveling around the country to get them!
Fantastic numbers of stations have been logged by several of the fraternity.
Louis Matullo, Washington, Pa., holds unquestioned lead in this department, having
identified 95 different stations! His list includes virtually every v.h.f. station
within a 500-mile radius, and is very close to the maximum possible under present-day
conditions. Lou is after more u.h.f. stations to add to the 7 he already has. There
are 29 high-band v.h.f. stations on his list, along with 59 on channels 2 through
6.
Lou keeps involved records of weather and signal strength, and has photographed
more than 50 different station identification slides and test patterns. He regularly
logs up to 20 stations a day, and on July 15, he caught 36. Most home viewers refuse
to believe that this many stations could be received in any day, but it's no record
for Matullo. The top, was 37; on September 9 of last year.
Richard Baker; Moberly, Mo., a schoolboy of 15, has 56 stations to his credit,
and some fine tropospheric DX, including WHAS-11 and WAVE-3, 390 miles, WLWD-2 and
WHIO-7, 450 miles, and Chicago, 300 miles, on all channels now in use, WAFM-13 and
WBRC-p, 525 miles, and WXEL-9, 600 miles. Seeing the name of Gordon Amery, Braymer;
Mo., listed among the 1952 observers, Baker made a trip up to compare notes. Both
were pleased to find that they were the same age, and in the same grade in school!
Observer Van Gunten, Berne, Ind., has 63 stations logged, and has identified
as many as 40 in a single 24-hour period. Akers, Charleston, W. Va., has 57, including
all on channel 2 except the nearest, WFMY-TV. He is deep in a valley, with very
mountainous terrain in the direction of Greensboro. Mellenbruch, Hiawatha, Kan.
also has 57.
The favorable nature of the Gulf Coast for tropospheric DX shows in the reports
of observers Atkisson and Blalock of Tallahassee, Fla. They report reception of
Cuban stations on all channels in the warmer months, over distances up to 600 miles.
Birmingham and New Orleans are also received frequently in Tallahassee. Walker of
Daytona Beach has received WGUL-11, Galveston, Texas, more than 800 miles across
the Gulf. Young of Orlando also received WGUL, about 775 miles, on September 13.
At 10:15 pm Young was able to get a fine clear photograph of their beautiful seagull
identification slide, and the signal remained in for about an hour thereafter. No
low-band DX was in evidence. Rogers, of Mobile, also has seen WGUL.
Schuman, McAllen, Texas, logs KTBC-7, Austin, 309 miles, and KGUL-11, 340 miles,
frequently. Even KPRC-2, Houston, 309 miles, can be received on a channel 11 antenna.
Landry, Friars Point, Miss., has KPRC, WSB-2, WAVE-3, WSM-4, WBRC-6, WAFM-13, WTTV-10,
KGUL-11, and WHAS-11 at distances from 285 to 450 miles. Hale of Natchez, Miss.,
has a similar list, covering about everything "from Natchez to Mobile; from Memphis
to Saint Jo ... " and Galveston to San Antonio, to boot.
A session of tropospheric DX that would look like Es, if it weren't
on high channels, is reported by Hedges of Kingman, Kansas. The night of May 21
WKY-4 and KOTV-6, his "locals" at 170 and 190 miles, were snow-free after about
8:45 pm, so he started looking around. Result: KFDX-3, 325 miles, WBAP-5 and WFAA-8,
360 miles, KSWO-7, 225 miles, KPRC-2, 600 miles, and WGUL-11, 625 miles. The steady
reception or slow-fading change of tropospheric DX, as contrasted to the more rapid
fluctuation of Es, was present on these signals. They lasted until around
11 pm.
Sporadic-E DX Reports by Station and Channel
Not all the high-band DX is logged along the Gulf or in Texas and Oklahoma. Sproule,
up in Toronto, lists WMAL-7 and WTOP-9, Washington, D.C., along with many nearer
in Ohio, New York, and Pennsylvania. Teal of Burlington, N. C., says that the high-band
stations give better service in that mountainous terrain than does WBTV-3. He gets
WSLS-10, Roanoke, and WLVA-13, Lynchburg, better as a rule than the Charlotte station,
though all are at about the same distance. The high-band stations run much lower
power; but they have superior mountain sites. Teal, has also received WROV-27, Roanoke,
120 miles, when the high-band signals were good;
High-band stations, in Ohio, Kentucky, Illinois; and Indiana are reported by
Guin, Russellville, Ala;, who looks at Atlanta 200 miles, on 8, 5, and 2 with considerable
regularity. May 27 was an occasion of particularly good reception from the north.
Adding a screen reflector made of chicken wire to his Skyline antenna has improved
his reception markedly.
TV DX received under unusual and probably favorable conditions is reported by
Radio Officer Proctor, of the S.S. Sabine. He and his captain see stations along
the Gulf and Atlantic seaboard at distances up to about 250 miles more or less regularly.
A quite different sort of DX is described by Haley, Estes Park, Colo., and Beard,
of Hayfork, Calif. Both are surrounded by mountains that provide a mass of reflections,
making it almost impossible to tell the true direction of the station coming through.
Haley caught a few minutes of sound and picture on channel 13 on December 18 of
last year. He assumes that it came from KLAC, Los Angeles, but that's more than
700 miles away, directly over the 13,000-foot Continental Divide.
Fig. 2 - Showing how the TV DX is divided among the low-band v.h.f. channels.
Beard's valley location, 200 miles north of San Francisco, is so full of reflections
that when he caught KFEL-2, Denver, on July 4, he was able to distinguish six separate
ghosts, all fading out of phase!
DX on u.h.f., too
True to predictions in the monthly DX forecast appearing regularly in Radio-Electronics,
DX is beginning to show up in the u.h.f. channels. Honors for the first u.h.f. report
that can be called DX go to Mrs. W. C. Breithaupt, Little Rock; Ark. She picked
up WJTV-25, Jackson, Miss., at 10:15 am, April 9, a 200-mile haul. Other u.h.f.
reports were contributed by observers Ross, Walker, Peters, Wieskamp, Teal, Hill,
Grave, Kuehn, De Haven, Melson, Collins, Kidd, Ashworth, Perry, Paul, Richards,
Cooper, Cafritz, and Carnes.
An Atlantic seaboard path that has produced many fine contacts for hams on 144
mc has shown itself capable of producing u.h.f. DX, too. Ashworth of New Bedford,
Mass., pulled in WVEC-15, Hampton, Va., around 8 pm October 3. It's about 450 miles,
the best u.h.f. DX yet reported by an observer. De Haven, Atlantic City, N. J.,
brought in WICC-43, Bridgeport, Conn., 150 miles, on August 25. Since then, Bob
has logged WVEC-15, WEEU-33, WGLU-59, and WHUM-61, all in eastern Pennsylvania ..
Midwestern reports include WTVO-39, Rockford, and WTVI, Belleville, Ill., by
Kidd, of Decatur, 170 and 100 miles, respectively. WSBT-34, South Bend, Ind., is
reported by Richards, Keensburg, Ill., more than 250 miles. WSBT is also mentioned
by Kuehn of Milwaukee, 130 miles. Melson, Niagara Falls, N. Y., has logged WKBN-27,
Youngstown, and WICA-15, Ashtabula, Ohio, 180 and 125 miles, respectively.
Over-water, coastal, and river-valley paths seem to produce u.h.f. DX in a manner
now well established in v.h.f. work. At Quogue, Long Island, Perry has received
WFPG-46, Atlantic City, nearly 150 miles, WHYN-55, Holyoke, Mass., and WKNB-30,
New Britain, Conn. A shot of well over 300 miles, mostly over salt water, WCOS-25,
Columbia, S. C., received by Walker, Daytona Beach, Fla., has already been reported
in the monthly DX column as an early u.h.f. record.
Co-channel and adjacent-channel interference, not supposed to occur in the "interference-proof"
u.h.f. region, has already reared its ugly head. Paul, Honeybrook, Pa., noting some
interference on his local WEEU-33 the night of October 3 (remember this was a big
night), turned his antenna and found the cause to be WKNB-30, three channels and
170 miles away in New Britain, Conn. (We repeat here the prediction made at the
time the u.h.f. allocations plan was first announced: There's going to be a lot
more interference between stations in the u.h.f. region than most people now anticipate.
When tropospheric propagation is good on u.h.f., it's terrific!) Observer Paul holds
the record, incidentally-8 u.h.f. stations identified, and in one evening.
The only West Coast u.h.f. report is from Cooper of Lafayette, Calif., formerly
of Ithaca, N. Y. Bob sees KCCC-40, Sacramento, 100 miles, and KMJ-24 and KJEO-47,
Fresno, 125 miles fairly regularly. This is made possible by a "relay rhombic" on
a hill about a mile away from and 500 feet above his valley location.
Some really rare ones
Nearly all the DX reports, v.h.f. and u.h.f., can be classified according to
well-established patterns. But every so often an observer comes up with a report
that cannot be explained by any of the known theories. Such is the reception of
KLAC-13, Los Angeles, by Phil Rader, Indianapolis, July 2. This far exceeds the
amateur 144-mc record of 1,400 miles, and it's three times the best that as
been done on 220 mc. Assuming that it's not a case of mistaken identification, how
did it happen? Phil also reports reception of PRF-3, Sao Paulo, Brazil, July 8.
Cooper calls our attention to a report that appeared in Broadcasting regarding
the reception of WKY-4, Oklahoma City, in England. The same publication also reported
KTNT-11, by a viewer in McAllen, Texas, No detailsv-vbut what DX, if true!
And here's the real killer. John Shipley, chief engineer of WKNB, New Britain,
Conn., called the writer one afternoon last summer to pass along information on
reported reception of their new channel-30 rig by a viewer in Ames, Iowa. The correspondent
reproduced the WKNB test pattern accurately, and correctly identified the pitch
of the tone that accompanied it. This neat 1,100-mile trick was turned shortly afternoon
on July 11. Can anyone explain it? We have a few things to learn, yet!
1 "TV DX in 1951," Radio-Electronics, January 1952, p 40.
2 "TV DX in 1952," Radio-Electronics, January 1953, p 45.
Posted March 8, 2022
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