Robotron G3E Shortwave Receiver User Manual g3 user s manual
Robotron Pty Ltd Shortwave Receiver g3 user s manual
UserManual.wiki
>
Robotron
>
G3E User Manual
Manual
Navigation menu
Upload a User Manual
Namespaces
Wiki Guide
HTML
PDF
Info
Views
User Manual
Discussion / Help
Navigation
![- 36 - The scanning method is selected using the appropriate button in the Scanning Control Panel: Scanning Control Panel Immediate Scanning (Searching) This is the simplest scanning method. Click on the Search button to select this scanning mode, then use the [>>] or [<<] buttons to scan either forward or backward from the currently tuned frequency. To stop scanning, press the Stop button (marked with a green square). To pause, press the Pause button (marked with two vertical bars). A signal is considered ‘found’ when the signal level is higher than squelch. Correct setting of the squelch value is therefore essential for scanning. If you set the squelch level too low, then scanning will stop even if there is no signal (the background noise will be higher than the squelch level). On the other hand, if the squelch level is set too high, then a useful signal may be missed because it will fall short of the squelch level. With a bit of trial and error, you will need to adjust the optimum setting for the squelch level (usually a few dB above the background noise floor). Scanner Configuration When a signal strength level is higher than the squelch level, this indicates that a signal has been found. You can configure the software to specify what action you want to be taken at this point. To access this configuration facility, go to Options | Scanning in the top bar menu.](https://usermanual.wiki/Robotron/G3E/User-Guide-447696-Page-37.png)
![- 38 - Note that the upper scanning speed limit may be restricted by the available CPU resources of your computer. When a signal is found and scanning pauses, waiting for the pre-set Delay time to expire, the countdown timer will appear inside the [<<] or [>>] buttons. If no Delay time was set and scanning is pausing until the signal disappears, then the [<<] or [>>] button will flash. Groups The Groups setting is useful for Memory Scanning, which will be described later: it serves to restrict Memory Scanning to particular memory groups only. Exclusions Sometimes it is desirable to exclude certain frequencies from scanning. This means that such specified frequencies should be ignored even if the signal level on these frequencies is higher than the squelch. The WiNRADiO G303 receiver application makes it possible for multiple frequency ranges to be excluded. This is done using the Exclusions button. When you press this button, you will open an Exclusions editor window, allowing you to enter a range of frequencies to be excluded. For these exclusions to become active, check the Enable excluding while scanning checkbox in this window. Frequency Range Scanning To be able to use Frequency Range Scanning, you need to set up the desired scanning ranges first. This is done using the Ranges button in the Options | Scanning top-bar menu.](https://usermanual.wiki/Robotron/G3E/User-Guide-447696-Page-39.png)
![- 40 - When the range definition is done, close this window, then close the scanner settings. Then activate the Range button in the Scanning control panel: Scanning Control Panel When you press the Scan Forward button [>>], the scanner will commence scanning from the start frequency of the first range. When the last frequency of the first range is reached, it will then continue onto the next range, etc. When it reaches the end of the last range, it will go back to the start of the first range and continue looping infinitely until a signal is found, or until manually stopped or paused. If you use the Scan Backward button [<<], the process will be exactly reversed (i.e. starting from the top frequency of the last range and working its way downwards). You can stop or pause this activity using the Stop or Pause buttons. If you use the Pause button, then restarting scanning using Scan Forward or Scan Backward buttons will resume the action from the paused frequency. If you stop scanning with the Stop button, then using the Scan Forward or Scan Backward buttons will recommence scanning from the initial (or the last) frequency again. If no ranges are specified in the Ranges list, then activating scanning in the Range mode will result in no action. An additional useful feature of frequency range scanning is that all found frequencies can be automatically stored in memory, even if the receiver is left unattended. To do this, enable the Auto Store checkbox in the Scan ranges set-up window, and specify the memory range to which the frequencies should be written. You can also specify a special Group Number to be assigned to such frequencies. When using the Auto Store option, you should also set the appropriate conditions for scanning when the signal is found (for example, pause when signal found, and resume after the minimum delay time will provide the fastest scanning and writing into memory).](https://usermanual.wiki/Robotron/G3E/User-Guide-447696-Page-41.png)
![- 66 - Appendix G – Frequency Calibration The G303 receiver series features an excellent frequency accuracy and stability for a receiver of its class. It is however possible to improve this accuracy yet further, by individual calibration. The receiver calibration is accomplished by inserting a reference frequency parameter in the wrg3.ini file which resides in the Windows directory. The reference frequency parameter consists of two lines of the following format: [ClockCalibration] receiver_serial_number=reference_frequency The receiver serial number can be obtained from the About box in the G303 application. The reference frequency is the actual frequency of the internal reference oscillator in Hz. This is nominally 20 MHz, i.e. 20000000 Hz. Each receiver is factory calibrated, so a correction to the nominal 20 MHz reference frequency already exists and is stored in the receiver's internal memory. This correction can be overridden by the new parameter in the wg3.ini file. To determine the true offset from a perfect tuning, firstly use 20000000 (i.e. the nominal reference frequency in Hz) as the new reference_frequency parameter. Say your receiver serial number is 02L27011: [ClockCalibration] 02L27011=20000000 Open the existing wrg3.ini file, add the above two lines, then save the file and start the G303 application. The frequency error will now be much worse because this new parameter overrides the original factory calibration. Then tune the receiver to a known frequency standard. A high-accuracy signal generator can be used, or one of the WWV Time and Frequency Standard stations. Observe the peak with the spectrum scope and listen to the beat frequency in the CW mode with a minimum IF bandwidth. Typically, this will be a negative number (for example, -652 Hz at 10 MHz). Then scale the frequency difference to 20 MHz. For example, if the frequency difference is -652 Hz at 10 MHz, it will be -1304 Hz at the 20 MHz reference frequency.](https://usermanual.wiki/Robotron/G3E/User-Guide-447696-Page-67.png)
![- 67 - Then subtract the frequency difference from 20000000. In our example, the resulting reference_frequency will be 20000000-(-1304)=20001304. The entire reference frequency parameter in the wrg3.ini file will be then as follows: [ClockCalibration] 02L27011=20001304 Save the wrg3.ini file, then restart the G303 application and observe the difference. To return to the original factory frequency calibration, simply delete the inserted two lines in the wrg3.ini file. You can also delete the entire file (which will however result in losing all current receiver settings and return to factory defaults for all of them). Did you know? The WWV Time and Frequency Standard stations which broadcast on 2.5, 5, 10, 15 and 20 MHz, have a long history that dates back to the very beginning of radio broadcasting. The call letters WWV were assigned to the US National Institute of Standards and Technology (then called the National Bureau of Standards) in October 1919. By December 1922, it was decided that the station’s purpose would be the transmission of standard frequency signals. The accuracy of the transmitted frequency was quoted as being better than 0.3 per cent. Nowadays the station frequency is controlled within one part in 1013, which represents frequency accuracy thirty billion times better.](https://usermanual.wiki/Robotron/G3E/User-Guide-447696-Page-68.png)
