| |
G0FTD > JAMMER 22.03.05 08:47l 145 Lines 7460 Bytes #999 (0) @ WW
BID : DD9906G0FTD
Read: DK5RAS GUEST
Subj: Cold War Jammers Part 3/4
Path: DB0FHN<DB0NOE<DB0GAP<DB0AAB<DB0FSG<DB0MRW<DB0WUE<DK0WUE<DB0RES<ON0AR<
GB7CIP<GB7SXE
Sent: 050321/1656Z @:GB7SXE.#38.GBR.EU #:25600 [Hastings] FBB7.00i $:DD9906G0FT
From: G0FTD@GB7SXE.#38.GBR.EU
To : JAMMER@WW
To : JAMMER@WW
Type : B
Date/time : 04-Feb 23:35
Bid : B29494G0FTD
Title : The Cold War Jammers (3)
They would then be able to listen, undisturbed, until the radio bureau
discovered the shift. Since Voice of America transmitted on several
frequencies at the same time, it wasn't easy for the radio bureau to
monitor all the frequencies at the same time.
Besides the local jammers, there were also long distance jammers in Russia,
Ukraine, and who knows where else. These directional antennas would be
aimed towards Estonia. Since they were so far away, their jamming
transmissions would reach us via atmospheric reflections.
The effectiveness of these long distance jammers was very dependant on the
weather and other factors affecting transmission.
Besides jamming, we also had the opportunity to transmit original
broadcasts. Right nearby, just one tram stop towards the center of town,
by the Heina Street railroad viaduct, was Tallinn Radio's second
program's broadcasting station, the so-called "railroad transmitter",
so named because it was located in three railroad carriages.
We could substitute for them with our medium wave transmitter, which
was basically the same as theirs. And we actually did this when the
"railroad transmitter" was being repaired.
In connection with this, we once had an interesting experience.
We had to stand in, with our medium wave transmitter Uragan, for
the "railroad transmitter", since it needed to be overhauled.
There was no direct link between us and the radio station.
The station's program was sent to us for transmission via the radio
bureau. The radio station and the radio bureau were located in
neighbouring buildings, at 12 and 14 Kreutzwaldi Street. The radio
bureau sent us the program, to the Sitsi objekt, over the direct phone
line. The radio program started at 6:55 in the morning. At the same
time, 6:45 - 7:00, the Voice of America's morning program was coming
in on medium wave, and which we were supposed to jam. But this time
the jamming was supposed to be done by the "railroad transmitter",
which was thereafter supposed to be taken away for repairs. I had
already set our transmitter to the radio program's frequency of 710kHz,
the phone line with the radio bureau had been checked and commuted to
the modulator, and the modulator had been adjusted to amplitude
modulation.
To check the transmission quality, we had a radio receiver on the
table, tuned to 710kHz. But the radio bureau forgot that the
transmission stations had been changed for that day. It was 6:50, when,
over the table radio receiver, I could hear a Russian woman yelling
and swearing in Russian - why isn't transmitter Uragan switched on and
jamming Voice of America! The radio bureau operator phoned us over
the same modulation line, over which the radio program should have
been sent. And all this was going onto the air, for all of Estonia to hear.
When the operator finally got tired and stopped her tirade, so as to
catch her breath, I was able to inform her as to who was, on that day,
doing the jamming, and who was transmitting the radio broadcast.
I knew that everything she had said had gone onto the air. For a moment,
there was total silence, and then the radio show could be heard over
the phone line. No one from radio bureau bothered us for some time.
Besides jamming, various other things were also done at the Sitsi
station. The Tartu radio stations first post-War medium wave transmitter
was built there, and then transported to Tartu. It was finally located
in the Tiigi Street jamming station's building. The transmitter was
built from the same Uragan type of transmitter as we had.
The constructor was Raul Pääro.
Both before and after me, many Electromechanical Technical School
graduates ended up working at the Sitsi transmission station. For
instance, the Minister of Communications Arvo Kaldma, and Kalju
Kallikivi, the director of communications at Estonian Energy.
The Sitsi transmission station's territory was surrounded by a
high fence. No outsiders were allowed to enter, not even the militia
(Soviet regular police). At the gate was a guard armed with a rifle.
The security team consisted of both Estonians and Russians. Sometimes,
when it got very boring, we would go into the basement with the guard
and shoot the rifle. But this was of course done only in secret.
The Sitsi station operated round the clock, was run by four two man
teams, with two technicians on duty during every 12 hour shift, during
the day from 8:00 to 20:00, at night from 20:00 to 8:00.
One snowy winter we built a huge snowwoman in the station yard, which
could even be seen from the other side of the fence, especially from
the tram window. Since the snowwoman's female anatomy was very visible,
we received a written reprimand from the Estonian Radio Centre's Chief
Engineer Gnipilt.
In 1958, my three compulsory years were up, and I left objekt nr. 65,
and the Estonian Radio Centre altogether, so as to accept a better paying
position at the Estonian Maritime Fishing Harbour's navigation centre.
We saw the construction of objekt nr. 602 with our own eyes, when we were
attending the Technical School, in 1953 - 1955. We could clearly see the
work in progress from the classroom windows. We asked teacher Arnold
Isotamm what kind of transmission towers these were. He wouldn't say,
although he obviously knew. Now, 46 years later, I can't say exactly
what year that was. But it was most likely 1954. The general building
of the jamming stations began about 1950 - 1951.
The whole Sitsi objekt territory was a triangular lot between Kopli and
Tööstuse Streets. Now it has been built full of residential buildings. At
one time, there were nothing but pastures there. Towards the city, the area
ended with a church on Kopli Street. From behind that, a fence stretched to
Tööstuse Street. As a matter of fact, the church was at first used as the
control room for jamming transmitters. But quite soon, a new building was
constructed for that purpose. And the church was converted into a residence
for Radio Centre employees.
On the Sitsi site there were three masts. These weren't actually antennas,
just the supporting structures. Two of them dated back to the independence
era, to the days of the Ranna Radio Station, in the sense that they had
been constructed out of the waste materials that had been left over from
the construction of the Türi broadcasting station antenna masts. During the
building of the Türi transmitter, a section of one mast had been damaged
while being unloaded in Tallinn harbour. This section was discarded, but
the
material was later used for the Sitsi site masts. Along with the jammers,
a third mast was also constructed, which was about 30 - 40 meters high.
The two original masts were higher. Unfortunately, I don't recall the exact
height, but it must have been about 60 meters. The antennas of all the
transmitters were hung up between these masts. The shortwave aerials were
symmetrically fed half wave dipoles; the medium- and long wave aerials,
unsymmetrical antennas , which were shorter than 1/4 wave. Theoretically,
the masts were tall enough to put up a full 1/4 wave antenna, but there
just wasn't enough space. Every transmitter had it's own individual aerial,
with the feeds coming out of the central building, through the windows.
(continued in part 4)...
Read previous mail | Read next mail
| |
