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Nova's Frequency Display provides a means to determine
uplink and downlink frequencies while communicating with a satellite. This
readout does not control radios.
The satellite whose data are shown is the AutoTracking
Satellite. 
Open the Frequency Display from the Main Menu/Utilities/Frequency Display
The Frequency Display screen looks like this:
Click on a button to jump to its function description
On the left (Uplink) side of this window, Transmit frequency is the uplink transmitter. L.O. Freq. is the Local Oscillator frequency of a transmit up-converter (transverter), if any. Doppler is the amount of Doppler shift that Transmit frequency will experience due to relative motion between the satellite and the observer (you). Freq.@satellite is the frequency at which the satellite will hear the uplink signal.
On the Downlink side, Freq.@satellite is the frequency that the satellite is transmitting on. Doppler is the Doppler shift experienced by the signal as it travels from the satellite to the ground. L.O. freq. is the receive down-converter local oscillator frequency and Receive frequency is the Doppler-shifted frequency at which the ground station will hear the satellite.
Adjust uplink or downlink frequencies by using the up/down spin buttons or by clicking on the frequency numbers with the mouse.
Linkage determines how one frequency responds when the other is changed. Please read this section carefully because these selections can be confusing.
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Normal means that if the Uplink frequency is changed , then the downlink frequency will also change in the same direction by the same amount. For example, moving up 10 kHz on the uplink will cause the downlink frequency to change upwards by 10 kHz also.
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Reverse means that moving upwards with one frequency will cause the other to move downwards by the same amount.
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Not linked means that changing one frequency (uplink or downlink) does not alter the other.
The following relationship apply in all Linkage selections:
|
Uplink Transmit frequency + Doppler shift = uplink Freq@satellite |
|
Downlink Freq.@satellite + Doppler shift = Receive frequency |
The 
Link buttons determine which "end" of the path is
"locked" and not changing. The Link button that is depressed is
"locked."
Examples:
| You are using a fixed-frequency satellite such as UO-14, you will depress the upper (@ satellite) link button. As a result, Nova will calculate the TX frequency that you should use in order for your signal to fall exactly on the satellite's input frequency, and you will see the correct RX frequency to tune for proper reception of the satellite. |
| You are using a passband-type satellite such as AO-40. In this case, you might want the lower link button depressed. In this case, your TX and RX frequencies are locked and the frequency at the satellite changes with Doppler shift. |
| You are using a passband-type satellite such as AO-40 but you are aware of KB5MU's "one true rule" and you want to keep your frequency at the satellite steady. Click the upper button and adjust your TX and RX frequencies as displayed by Nova. |
| For EME (Moonbounce, click the upper button because your echoes depart from the Moon on the same frequency at which they arrived |
Select the desired frequency pair from the Select drop-down box. See Setup (below) for how to add or edit entries in this box.
Click the 
Setup button to edit entries in the satellite's database. This will
open the Frequency editor. Here you can create new entries, update existing entries, or
delete them.
The 
Satellite button allows selection of the AutoTracking (and therefore the
Frequency Readout) satellite. Each satellite has one or more frequency entries in
its database. If a satellite's frequency has not been initialized yet,
Nova uses 100 MHz by default.
Clicking the 
Minimize button hides the main Frequency Display window and shows the
data along the bottom of Nova's main screen. This option is included to
reduce screen clutter. Here is what it looks like when it is minimized:
Buttons on the status bar have the same functions as similar buttons on the main display.
The small Frequency Display can be docked to the top or bottom of the main Nova window or the bottom of a View. Drag the small frequency display so that its title bar touches the top or bottom edge of the screen or the bottom of a View. |
The 
Lock button temporarily removes Doppler shift from frequency
calculation. This is handy during setup when you are trying to set
frequencies. If Doppler is on (the Lock button is up), then all
frequencies can be changing by themselves while you are trying to set the,
Clicking the Lock button causes them to "hold still." You may
also want to click the Link button.
The 
Expand button can simplify the Frequency Display screen.
Clicking it alternately shows or hides the lower lines of the display.
These data don't change so it might not be necessary to see them all the time.
There are three steps of expansion.
As in other windows, the 
Font size button sets the font size.
Notes:
- Under normal circumstances, you cannot edit the Doppler values. However, if the Lock button is depressed, temporary Doppler values can be entered by clicking on the appropriate box.
- The Frequency Display satellite is the same as the AutoTracking satellite. Frequency display Doppler values are calculated from the AutoTracking Observer's location