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On November 15, 1945, amateurs in U.S. are allowed back on the air -- but only on 10 and
2 meters. By 1946, Amateurs get most of the bands back except for 160 Meters,
this was used by LORAN and other services and was not available to Amateurs.
Over the next several decades 160M would be reopened, a little at a time.
1945 - Amateurs are allotted the 6 meter band 50-54 Mc. The 2 1/2 meter band is
moved to 144-148 Mc. With the exception of some FM, all phone operation is with
AM.
1945 6 Meters. Pioneers utilized CW, AM, and experimented with NBFM. Antennas
included rhombics, corner reflectors, folded dipoles, and of course Yagi's. The
first 2-way QSO involving "skip" was reported to have taken place on April 23,
1946 when W1LSN of Exeter, NH worked W9DWU of Minneapolis, MN. This and many
other contacts were made on that night via a combination of aurora and
sporadic-E. The distance of this contact was 1100 miles.
1946 - Amateurs make the first Meteor Scatter contacts. On the night of October
9, 1946, the night of the Giacobind-Zinner Comet, and its associated meteors,
Amateurs made their first two-way contacts via meteor scatter on the 6M band,
the propagation lasted 3 hours with reports from the east and midwest part of
the USA. However it was not until Oct 22, 1953 that a 2M two way contact was
made between W4HHK and W2UK. Transoceanic 6M contacts are made in late 1946.
http://www.ac6v.com/history.htm
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In November 1945, U.S. amateurs were allowed back on the air on the
10 meter, 5 meter, and the new 2 meter band. The 5 meter band
from 56-60 mc was temporary--by March 1946 we were moved in
the great post war frequency shuffle to our new 6 meter home
from 50-54 mc. As for the new 2 meter band, it replaced our
old 2 1/2 meter allocation which ran from 112-116 mc.
http://www.twiar.org/aaarchives/WB026.txt
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The World War II ended on August 17, 1945. No more than 4 days later, the US
hams were back on the air on VHF ! Europe restarted more slowly. The format of
English licence changed, allowing more flexibility, and the first stations were
heard on the air in 1946. By Summer 1946, the US hams saw all their amateur
bands restored from 3.5 to 30 Mc.
New modes were introduced, and more frequency spectrum was allocated for amateur
operation world wide, reflecting the importance that is attached to it by the
international community. The old 5 and 2.5m bands were replaced with the new 6
and 2m bands, always active nowadays.
http://www.astrosurf.com/luxorion/qsl-ham-history9.htm
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1947 After the Second World War, the ITU held a conference in Atlantic City New
Jersey U.S.A. with the aim of developing and modernizing the organization. Under
an agreement with the newly created United Nations (UN), it became a UN
specialized agency on 15 October 1947, and the headquarters of the organization
were transferred in 1948 from Bern to Geneva.
Amateur Radio was defined and still is, as “A service of self training,
intercommunication and technical investigation carried on by duly authorised
persons interested in radio technique solely with a personal aim and without
pecuniary interest.”
http://www.ham-radio-europe.co.uk/why%20is%20amateur%20radio%20unique.htm
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Radio Conference took place in Atlantic City, New Jersey, on May 15, 1947
10GHz is probably, in the UK at least, the most popular of the amateur microwave
bands. It has seen some sixty years of development since the first experimental
contacts made by W2RJM and W2JN in the USA during 1946. These two "pioneers"
could not have known what was to follow their 2 mile (3km+) contact! A year
later, in 1947 the world 3cm record was extended to 7.65 miles after a contact
between W6IFE/3 and W4HPJ/3. W6IFE is now the callsign of the San Bernardino
Microwave Society, the oldest amateur microwave group in the world and one with
a fascinating history of its own.
http://www.g3pho.free-online.co.uk/microwaves/history.htm
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But some interesting ‘straight' receivers were also being built, a good example
being one by Hodinin, OK2MV, who incidentally was the first OK to work England
on 58 MHz in June 1947, with G5BY at the other end (who else?).
http://www.uksmg.org/50yrsof50megspt5.htm
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While the first 3 cm contact was made in May of 1946 (James W2JRM and Charles
W2JN, 2 miles (3.22 km)), Tommy W6IFE (shortly before returning to California)
and W. Kenedy W4HPJ, quickly stretched this record out to 7.65 miles (12.31 km).
These early contacts would serve as an indicator as to how successful this band
would eventually be. To this date, 3 cm. is by far the most populated of the
microwave bands above 13 cm.
Tommy W6IFE is credited with opening the 9 cm band [The ARRL UHF/Microwave
Experimenter's Handbook, page 1-8]. Early on, Tommy had to construct both ends
of the microwave equipment used on his microwave shots. On June 5, 1947, Tommy
is credited with working 186 miles (299.46 km) on 9 cm.
April 25, 1948, Tommy W6IFE is credited with working a 150 mile (241.5 km)
record path with W6ET on the 13 cm band.
http://www.ham-radio.com/sbms/historyOW.html
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anniversary of the World Record contact between Clarrie VK5KL and Eugene
W7ACS/KH6 took place at 1240 CST (0310 UTC) on 26 August 1947 on the six metre
band, 50 to 56 MCs. (At the time, frequencies were referred to as Megacycles or
MCs, or megs for a short title.) Clarrie made the contact while he was living in
Darwin. VK5 callsigns then were used for South Australia and the Northern
Territory. The distance was considered to be 5350 miles or 8610 km. I presume
Clarrie will open a bottle of champagne to celebrate the memory of that contact
50 years ago!
http://www.uksmg.org/vkww.htm
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In 1947, the World Telecommunications Conference in Atlantic City allocated
amateur bands worldwide and added 2 metres, 70 centimetres, 23 centimetres and
harmonically related microwave bands. One must remember that amateurs used keyed
continuous wave (c.w., morse) or, in the case of telephony transmissions,
amplitude modulation (a.m.)
http://www.qsl.net/gi8flq/4m&up_gi_history.html
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Poválečný vývoj povolovacích podmínek
Hned po válce začala pracovat komise ČAV na návrhu nových povolovacích podmínek.
Ty byly zaslány ministerstvu pošt někdy v závěru roku 1945, a návrh požadoval
např. "přidělení ... pásma od 110 Mc/s až do nekonečna."
V podstatě platily "staré" předválečné koncesní podmínky a uvolněna byla pásma
56.0-60.0, 112-118, 224-230, 408-420, 2.300-2.450, 5.250-5.650, 10.000-10.500 a
21.000-22.000 Mc/s jak pro telegrafní, tak telefonický provoz, a to s příkonem
50 W.
V roce 1949 byly ve VMP č. 5/1949 otištěny nové, modernizované "Koncesní
podmínky pro vysílací radioelektrické stanice pokusné", a současně zrušena
platnost stávajících z roku 1946 včetně všech dodatků.
Povolená pásma - 50-54 Mc/s dočasně, 144-150 Mc/s z toho 146-150 dočasně),
220-225 Mc/s dočasně, 420-460 Mc/s spolu s leteckou navigací, která nesměla být
rušena, a pásma 1215-1300, 2300-2450, 3300-3500 (dočasně), 5650-5850,
10000-10500 a 21000-22000 Mc/s.
viz take http://www.ok1uu.com/1952.htm
V roce 1954 vyšly další povolovací podmínky, ve kterých všechny operátorské
třídy v rámci svého povoleného příkonu mohly používat i VKV pásma 85.5-87 MHz,
144-150 MHz *), 220-225 MHz *), 420-460, 1215-1300, 2300-2450, 3300-3500,
5650-5850 MHz, 10.0-10.5 a 21.0-22.0 GHz. Na základě žádosti podané
prostřednictvím ÚRK (Ústřední radioklub Svazarmu) bylo možné mimořádné povolení
k pokusům s jinými druhy vysílání (nespecifikováno).
U údajů označených *) došlo ke změně k 15.3.1959, a to: pásmo 2 m omezeno na
144-146 MHz, a k uvedenému datu bylo též zrušeno pásmo 86 a 220 MHz.
V roce 1961 došlo k dalšímu omezení pásma 430 MHz na 430-440 MHz, bylo zrušeno
pásmo 3 GHz a 5 GHz omezeno na 5650-5800 MHz.
V roce 1979 bylo amatérské pásmo v oblasti 20GHz přesunuto na 24000-24050 MHz, v
roce 1982 nám přibyla pásma 24,050-24,250 GHz, dále 47,000-47,200,
75,500-76,000, 142-144 a 248-250 GHz.
http://www.crk.cz/CZ/VYVKONC.HTM
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Ze zdrojů nalezených na internetu sestavil OK1VPZ v říjnu
2007.
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