|Links||UNC Skynet||20m skynet interface||Log of 20m results.||NRAO Skynet main||observing advice|
Details for various kinds of observing projects
|Main Observing Advice||Mapping/Imaging Advice||Spectrum Observing Advice||Pulsar observing|
the mode is selected in one of the "Add Radio Observation" dialogs:;
Select High Resolution Mode Set the two frequencies to 1420 and 1420 MHz Set Number of channels to 1024 or 4096 Galactic Hydrogen on the galactic plane: pattern: Track; duration: 60 seconds; integration time: 1 sec Nearby Extragalactic galaxies: pattern: On/Off; duration: 200 seconds; integration time: 1 sec; Offset: 4 degrees And repeat the on/off 2 or more times. For more distant objects, try longer durations and more repeats. Calculate the frequency of the HI line for the velocity of the object, and set one of the frequecies (or both) to that frequency, in MHz.
Select High Resolution Mode Set the two frequencies to 1664 and 1664 MHz Set Number of channels to 1024 or 4096 Select a source that is likely to have OH emission such as Orion A or W3 Pattern: On/Off; duration 120 seconds; integration time 1 sec; Offset: 4 deg. For both HI and OH: Set the two frequencies to 1418 and 1668
NOTE: in high resolution mode, it is not recommended to do maps or daisies, as there is no software available to process such data. If you do mapping in high resolution mode, use integration time recommendations from the mapping advice page.
|Receiver||Filter||Center Frequency||Available Bandwidth||Num Channels|
|Rx1_2||HI 1355-1435 MHz||1395 MHz||80 MHz||164|
|Rx1_2||OH1 1630-1730 MHz||1680 MHz||100 MHz||205|
|Rx1_2||OH2 1650-1750 MHz||1700 MHz||100 MHz||205|
|Rx1_2||all 1350-1750 MHz||1550 MHz||400 MHz||820|
|Rx8_10||8000-10000 MHz||settable by user||500 MHz||1024|
You may enter any desired two frequencies into the Skynet web form, and
the system will adjust them to be multiples of 15.625 MHz apart.
The two frequencies may not be separated by more than 480 MHz.
Number of Channels
The number of channels may be selected from the following table, which shows the channel spacing in each case.
|Number of Channels||channel spacing in frequency||velocity spacing (21cm)|
|1024||15.26 kHz||3.22 km/sec|