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AlexanderSAQKeymaster
Dear Bob,
We cannot hear any sound from the transmitter set that can be connected to the keying. The transmitter set is equipped with two Bartlett Hayward flexible couplings between drive motor/gearbox and gearbox/high frequency generator. According to the RCA description of the transmitter, a special lubricant is needed to these couplings ”to absorb the chock in telegraph service”.However, the keying is easily heard in the transmitter hall, as four huge relay-switches are operating for the speed compensation. Moreover, these relay-switches are cooled with compressed air in order to blow out arcs and cool the contact surfaces. The sound from the cooling air is very aggressive and varies with the keying, so use of ear protections is recommended.
Ola Hernvall / AlexanderSAQ
AlexanderSAQKeymasterDear Bob,
Thanks for the question.
No, the alternator load is not kept constant, the load variations are handled by the power network.In order to keep the frequency constant at keying, additional torque is given by the drive motor at key-down to match the increased power to the antenna. The drive motor is an induction motor. The supply lines to the motor are equipped by transductors, i.e. choke coils with variable inductance, so the voltage to the drive motor can be adjusted between 1500 and 2300 V. The rotor winding of the drive motor is connected to variable liquid resistors, so the rotor resistance can be varied over a wide range. At key-down the inductance of the transductors is reduced and also the rotor resistance is reduced, both measures contributing to increased torque. The additional torque can easily be adjusted by the liquid resistors to match the increased load. A German radio amateur has analyzed the frequency variation at keying and found it to be within +- 10 Hz.
Ola Hernvall /AlexanderSAQAlexanderSAQKeymasterDear Laszlo,
Yes, this is correct. Unfortunately, on this year ‘s Alexanderson Day, we are unable to air any transmission, due to maintenance. There will be start-ups of the Alexanderson alternator which can be monitored live on our YouTube channel. See more information on http://www.alexander.n.seRegards,
Fredrik/AlexanderSAQAlexanderSAQKeymasterSorry!
Of course its on SATURDAY December 24th and not Thursday…thanks for noticing. 🙂
//Fredrik – AlexanderSAQAlexanderSAQKeymasterHi all!
We are looking forward to hearing your stories, how you spent Christmas Eve morning, listening to SAQ.
Please write a short story to info@alexander.n.se and let us know how it was.
Bonus for attached pictures 😉Thank you!
//Fredrik – AlexanderSAQ
P.S. Don’t forget to see the live video stream of the transmisson on http://www.alexander.n.seAlexanderSAQKeymasterHi all!
Tests were done today Tuesday Dec 20th at around 10 UTC, see link below.
http://lf-radio.de/cgi-bin/ki/plot_channel.cgi?date=16-12-20&freq=17.2KHzNext test will be on Friday Dec 23rd at around 09.00 UTC.
Looking forward to hearing from you all on Christmas Eve.
//Fredrik – AlexanderSAQAlexanderSAQKeymasterDear Andreas,
We are happy to hear that you will come and visit the World Heritage Grimeton Radio Station this summer.
A fantastic site to visit. Our summer transmission schedule, looks like this:– July 3rd (Sunday): Alexanderson Day. A full day event (detailed schedule will be posted on our web site about 4 weeks prior to the event) with many activities in and around the station. Display of the Alexanderson alternator by people who worked at the station when it was in operation. There will also be two occations (morning & afternoon) of startup and transmission of a message over the antenna that day. A great event!
AlexanderSAQKeymasterDear Lutz,
Thanks for the nice tip – this is a great idea!
However we do not always know the exact date and time for the next transmission until shortly before the planned date, due to the fact that we don’t have regular access to the antenna. Access is granted but never guaranteed only weeks before a planned transmission.
But we would like to improve our communication with all listeners, so a count down clock on our website some weeks before a planned transmission is definitely something we will try!
Fredrik /AlexanderSAQAlexanderSAQKeymasterDear Marc,
Yes, today we got access to the antenna and started the transmitter at around 14:00 UTC for some testing to make sure everything is working OK for tomorrow.
The test was successful so everything is looking good for tomorrow’s transmission.Fredrik /AlexanderSAQ
AlexanderSAQKeymasterDear Bart,
We are exited to hear about your efforts to receive SAQ far away in California and we will do our very best to get the signals over to you.
Don’t miss the live video broadcast of the SAQ transmission, here on alexander.n.se.Fredrik /AlexanderSAQ
AlexanderSAQKeymasterDear John,
The Alexanderson alternator is driven by a 600 horse power asynchronous two phase 2300V electric motor, driving the high frequency generator via a gear box. The transmitting frequency is in direct proportion to the speed of the motor. One of the great challenges with the SAQ transmitter is to maintain the motor speed at a constant rate, both when the transmitter is idling (Morse key is up) and when it is transmitting (Morse key is pressed down). This is done by an automated control system, however at start-up it needs “tuning assistance” to find the right frequency. After the initial tuning of the transmitter, we normally can keep the frequency between 17190 and 17210 Hz. On the electric motor, with a speed of 711,3 revolutions per minute, this represents a maximum deviation of a single revolution per minute between idle running and full load.Fredrik / AlexanderSAQ
(thanks to Ola Hernvall for technical assistance)AlexanderSAQKeymasterMoved from comments: Radu / YO8SXX
YO8SXX – amateur radio qth SUCEAVA-ROMANIA, loc. KN37CQ
Reception report
______________________________________________________________________________Date: 24.10.2015
Frequency: 17,2 KHz
Mode: CW
UTC: start time 10:00, end time 10:09
CALL: SAQ Grimeton Suedia
Signal report: 579 / 599, slight QSB, loud QRN from artificial sourceMessage received:
***********************************************************************************
vvv vvv vvv de saq saq saq……
cq cq cq de saq saq saq
this is grimeton radio/saq in a transmission on united nations day using the alexanderson 200 kw alternator on 17.2 khz ; the message is written by paskberg ii paskberg school in varberg . =
; understand the rep(?)ugees situation . not their choice , not their fault . refugees are an asset . refugees are also human beings . treat the refugees the way you want to be treated . all countries must help . war separates families . fight war , g ii not refugees . fight terrorism . learn to live with other cultures . eu (sn) everyone has the same value . help out , next time it could be you . =
signed : world heritage grimeton and the alexander-grimeton veteranradios vaenner association a^r =
info : we do not require any qsl reports on this transmission =
de saq saq saq s^k
***********************************************************************************receive and written by: Radu Chisalita/YO8SXX
Note:
– This report includes attached audio files containing the recording of parts of the issue and the whole final message.
– Receiving equipment: VLF converter 10-200 KHz to 10,01-10,2 MHz, yaesu FT1000 MP transceiver, inverted V antenna for 80 m amateur band, audio interface for PC recording.YO8SXX, op. Radu Chisăliţă (Radu)
Str. Gheorghe Doja nr. 18A loc. Suceava RO720074 Romania
Email: raduchisalita@yahoo.com
See detail on http://www.qrz.com/db/yo8sxxThis Report and attached audio files was sent to SAQ Grimeton Suedia
AlexanderSAQKeymasterMoved from comments: OE3FFC, Franz
Your fine transmission on the SAQ-UN-Day i must listen on web-sdr uni twenty, because i had big QRM/QRN from my neighbor. Sri. The sigs during the whole transmitting-time were fine with S 7.
So i´m looking forward to your next transmission with the “old boy” with my new homebrew rig.
Many thanks for all,
de — . …– ..-. ..-. -.-. :))AlexanderSAQKeymasterMoved from comments: G3JNB
Very heavy static S9+60 covered most of the transmission this time. 100ft LW, VLF converter to FT2000.
Disappointing but glad the Old Lady did her stuff again.73 Victor G3JNB>
AlexanderSAQKeymasterMoved from comments: OK1DSO , JARDA
SAQ-UN Day Transmission very very strong S / N + 30 db, Receiving Mini Whip. PC and saqrx_exe, near Prague airport
AlexanderSAQKeymasterMoved from comments: Erik PE1NOJ
Strong signal (RST 578)
Eddystone VLF receiver and Mini Whip
Zevenhuizen NetherlandsThank you Lars
AlexanderSAQKeymasterMoved from comments: RA4HGN
Heard SAQ RST 579. My QTH Samara, LOC: LO53CF, QRB 2390 km, Setup:
1. ANT – long wire 80 m
2. RX – sound card PC
3. Soft – GNU Radio
https://drive.google.com/file/d/0B9Injxn2JYHbOGQwVlpzbEx6SGc/view?pli=1AlexanderSAQKeymasterMoved from comments: Bert, SM1CJV
Heard the Old Lady with +28db over noiselevel,RX computer+soundcard,antenna half Square 10Mhz.
73 de SM1CJV/BertAlexanderSAQKeymasterMoved from comments: Stig Linnarud, SM4EFQ
Långbanshyttan 2015-10-24
Har idag emottagit er sändning på 17.2 KHz ,
RST 579, ngt QRM men annars stabil signal.
TACKAR ! Vi höres. 73 Stig.AlexanderSAQKeymasterMoved from comments: DF7DJ, Bert
Nice transsmission today. Copied very good in the near of Dormund with homemade converter and aktive antenna.
AlexanderSAQKeymasterMoved from comments: Hajo
Very good and stabil signals and
a very good message to all people of the whole world.
Thank you dear Lars!AlexanderSAQKeymasterDear Brian,
The simple answer to your question is that we have no modulator, it is pure CW we are sending out. There is however no prefect square wave but it has a short rise- and decay time (about 12 ms).
However, Arne Siko here at the Alexander association had a data simulation made on a rough theoretical model of the antenna, and in the curves of that simulation one can discern an overlay that would be perceived as a 1100 Hz tone. We have never thought of this, as we see an overshoot in the amplitude at approximately 15 ms, that we thought little of, but not found any explanation. All this can be seen on the attached report.
http://alexander.n.se/wp-content/uploads/2015/10/Siko-antennsignal-1-tecken.png
http://alexander.n.se/wp-content/uploads/2015/10/Antenna-current-calculated-Siko.png/Fredrik Wiklund @AlexanderSAQ with help from Ola Hernvall
AlexanderSAQKeymasterClub Station SP9MOA (moved from comments)
Thank you for publishing our pictures. We send the video
AlexanderSAQKeymasterAlois Wolf / DK4PB (moved from comments)
Danke!
War eine tolle Sendung, sehr gut hier in Deutschland aufzunehmen.
Antenne: 60 m Longwire
Receiver: Telefunken ELK639
Signale: 599Danke für die QSL-Karte!
AlexanderSAQKeymasterErik Knol / PE1NOJ (moved from comments)
cq cq de saq saq saq = this is grimetonradio/saq in at ransmission
using the alexanderson 200kw alternator on 17.2khz = 90 ii 90 years
ago, on july 2nd ii 2nd, grimetonradiostation/saq was inaugurated ii
inaugurated by his majesty gustaf v ii gustaf v, king of sweden.
nowadays the site is open for everyone and belongs to all people of
the world = signed: world heritage grimeton and the alexander-grimeton
veteranradios vaenner association =for qsl info please read our
website:www.alexander.n.se ii http://www.alexander.n.se = – info = we are we
are sorry but the transmission at 09:00 wtc did not work because ii
because of a short circuit in the antenna and no transmission was
possible = de saq saq saq SKsignal received at 448
antenna Miniwhip and Eddystone VLF receiver73’s Erik Knol PE1NOJ
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