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en:lesson09 [2019/10/09 14:58]
golikov
en:lesson09 [2021/04/06 09:39] (current)
golikov
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-====== Telegraph code ======+====== Telegraph code receipt ​======
  
-The telegraph code (or, more simply, ​transmission using Morse code) is still in use. +The telegraph code transmission ​(or, simply, Morse code transmission) is still used by many small units to transmit a beacon ​signalA beacon represents a periodically ​transmitted signal ​(most often provided ​once a minute or so) which contains the name of spacecraft ​unit (call sign) and the most important telemetry - voltage of the on-board ​power supply ​sourcestate of the batteries and solar panels, temperature of various points of the spacecraft unit, etcReceipt of these signals ​can help users to solve the following tasks:
-many small beacon ​devicesThe lighthouse is called +
-periodically (most often once a minute or so) the transmitted signal, ​which +
-contains the name of the spacecraft (call sign) and the most important +
-telemetry - voltage of the onboard ​power supply ​networkcondition ​of batteries and solar +
-batteries, temperature of various points of the device and so on. +
-Accepting ​these signalsthe following tasks can be solved: +
-  * give the opportunity to receive a signal "by ear". Unlike digital signals, which are audibly heard as hissing or buzzing, these signals have a well-recognized,​ “lively” character. The simple fact of receiving the selected device is usually impressive; since the reception uses only the simplest means, it is the reception of telegraph signals that is primarily used when testing equipment and the first attempts to use it; +
-  * demonstrate the Doppler effect. The tone of the signal, due to a change in the relative speed of the device during reception, changes strongly enough so that it can be heard even without musical hearing. This is one of the few experiments available where the Doppler effect is observed directly for electromagnetic waves; +
-  * Element of an unordered list to demonstrate the appearance of the device over the horizon, as well as a change in signal strength when it passes over the station; demonstrate the correspondence of the time of these time phenomena calculated on the basis of orbital data using special software.+
  
 +  * to enable receipt of the signal "by ear". Unlike digital signals, which are audible as hissing or buzzing, these signals have a well-recognized,​ "​live"​ character. The simple fact of receipt usually makes a strong impact; since only the simplest means are applied for transfer, we can evidence receipt of telegraph signals which is primarily used when testing the equipment and when first trying to apply it;
 +  * to demonstrate the Doppler effect. The tone of a signal arising due to changes in the relative speed of the unit registered in the process of changes taking place in receipt in the scale which is enough that it can be heard even without a musical talent. This is one of the few available experiments in which the Doppler effect is observed directly for electromagnetic waves;
 +  * element of the non-numbered list - demonstrate appearance of the unit from behind the horizon, as well as changes in the signal strength when it passes over the station; demonstrate correspondence of time actual for these phenomena with time calculated on the basis of orbital data, provided using special software.
  
-To receive the telegraph ​code (also called CW - Continuous wave) the following software is used: +The following software is used to receive the telegraphic ​code (also called CW - Continuous wave):
-  * SDR # for receiving a radio signal; +
-  * Orbitron for tracking the satellite and taking into account the Doppler effect;+
  
-Launch SDR # and select the type of radio: RTL-SDR connected via USB.+  * SDR# software for radio signal receipt; 
 +  * Orbitron for satellite tracking and Doppler effect control; 
 + 
 +Launch ​the SDR# software ​and select the radio receiver type: RTL-SDR connected via USB.
  
 {{:​06image002.png?​200|}} {{:​06image002.png?​200|}}
    
-In the Radio section, set the switch to USB mode and set the Bandwidth ​to 5000.+Set the switch to the USB mode and set the bandwidth ​to 5000 under the "​Radio"​ inscription.
  
 {{:​0901.png?​200|}} {{:​0901.png?​200|}}
  
-Make sure the Filter Audio” checkbox ​is unchecked.+Make sure that the "Filter Audio" point is unchecked.
  
 {{:​005.png?​200|}} {{:​005.png?​200|}}
    
-Next, you need to increase the signal ​gain. To do this, click on the gear.+Further ​you need to increase the signal ​amplification. To do this, click on the gear icon.
  
 {{:​06image004.png?​200|}} {{:​06image004.png?​200|}}
  
-Move the slider so that the noise level rises by about 10dB.+Move the slider so that the noise level increases ​by about 10 dB.
  
 {{:​05image012.png?​200|}} {{:​05image012.png?​200|}}
  
-Launch Orbitron and update TLE first. Click on the tool button.+Launch Orbitron and update TLE firstly. Click the button ​with a tools indication.
  
-{{:01image009.png?400|}}+{{:en:image_43.png?500|}}
  
-Press the zipper ​button to update ​the TLE.+Click on the lightning ​button to update TLE.
  
-{{:0902.png?400|}}+{{:en:​image_41_.png?500|}}
  
-Click the Download ​TLE button.+Click on the “Load ​TLE” button.
  
-{{:01image011.png?150|}}+{{:en:image_26.png?150|}}
  
-Download amateur.txt+Download ​the amateur.txt ​list.
  
-{{:0903.png?400|}}+{{:en:​orbitron_4.png?400|}}
  
-Only the satellites transmitting the telegraph code will appear ​in the side list on the right. Select the following satellites.+Only satellites transmitting the telegraph code will show up in the side list provided ​on the right. Select the following satellites.
  
 {{:​0904.png?​150|}} {{:​0904.png?​150|}}
  
-The selected satellites will be shown in the main program ​window.+All selected satellites will be shown in the main software ​window.
  
 {{:​0905.png?​400|}} {{:​0905.png?​400|}}
  
-Then go to the Calculation tab and click on the Calculation button.+Proceed ​to the Calculation” tab and click the Calculation” button.
  
-{{:0906.png?400|}}+{{:en:​image_172.png?500|}}
  
-The satellite ​will automatically ​calculate the flight time of the satellites. Go to the Rotor / Radio tab and make sure the tracking button is pressed.+The satellites'​ overflight times will be calculated ​automatically. Go to the "Rotor/Radio" ​tab and make sure the tracking button is pressed.
  
-{{:0907.png?400|}}+{{:en:​image_173.png?500|}}
  
-In the window ​with the reception ​frequency (Dnlink / MHz) the following ​correct frequency ​should be set, reduced by 3 kHzso that the signal is located ​in the center of the band:+The box with indication of the receipt ​frequency (Dnlink/​MHz) ​must be set to the next correct frequency, reduced by 3 kHz so that the signal is centered ​in the band:
  
   * CUBESAT XI-IV (CO-57) 436,​8475   * CUBESAT XI-IV (CO-57) 436,​8475
en/lesson09.1570622329.txt.gz · Last modified: 2020/03/25 16:03 (external edit)