Satellite operation is difficult to control. Anyone who wants to fully utilize the potential of a satellite transponder and have an excellent signal on both the uplink and the downlink needs to pursue:
- rotate antennas in azimuth
- rotate antennas in elevation
- debug RX (TX) on downlink
- debug TX (RX) on the uplink
- make a connection
- write down the connection
Doppler effect
Pri LEO FM satelitoch ako sú SO-50 a AO-51 je Uplink v pásme 2m a Doppler effect je menší ako na 70cm, takže väčšinou postačí vysielač nastaviť na frekvenciu uplinku. Doppler na downlinku v pásme 70cm je však trikrát tak veľký ako v pásme 2m a aj keď FM modulácia je zrozumiteľná aj pri menšom rozladení, ladeniu na 70cm sa nevyhneme. Ak však nemáme zariadenie pripojené k počítaču s programom HamRadio Deluxe.
Calculating the Doppler effect in HamRadio Deluxe
The Doppler effect is calculable, which HamRadio Deluxe uses in the Satellite Tracking function. So how to use this feature?
- We will insert the current Keplerian data into the "amateur.txt" file in the Satellites subdirectory
- We will connect the device to the computer with a CAT cable
- After starting HamRadio Deluxe, we select the manufacturer, radio, COM port and transmission speed. If we have CAT powered from the COM port, we also select the output from which the supply voltage is taken (DTR or RTS). Of course, the device must be switched on and CAT configured
- The correct connection is indicated by loading the control screen, where the frequency is lit. If it didn't work, check the settings or the CAT cable
- Now tap on the Satellites icon in the top menu, which will open a window
- We select the ones we are interested in from the list of satellites
- Tap on the Observer folder and enter your position, confirm Add
- We tap on the Ground Control folder. We select satellite and mode. VFO zaškrtneme RX a do políčka Satellite napíšeme Downlink frekvenciu. Napravo pod názvom zariadenia vidíme frekvenciu prepočítanú o Dopplerov posun frekvencie. Tá sa samozrejme s pohybom satelitu mení
This is how the abbreviated tuning plan looks like during the AO-51 flyby:
| Satellite | Date / Time | Azim | Elev | Receive | Transmit |
|---|---|---|---|---|---|
| AO-51 | 02-Dec-2006 16:56:00 | 76.6 | -1.1 | 435.305.386 | 0 |
| AO-51 | 02-Dec-2006 16:56:30 | 73.1 | -0.2 | 435.304.883 | 0 |
| AO-51 | 02-Dec-2006 16:57:00 | 69.3 | 0.7 | 435.304.323 | 0 |
| AO-51 | 02-Dec-2006 16:57:30 | 65.2 | 1.5 | 435.303.704 | 0 |
| AO-51 | 02-Dec-2006 16:58:00 | 61.0 | 2.1 | 435.303.031 | 0 |
| AO-51 | 02-Dec-2006 16:58:30 | 56.5 | 2.7 | 435.302.308 | 0 |
| AO-51 | 02-Dec-2006 16:59:00 | 51.9 | 3.1 | 435.301.545 | 0 |
| AO-51 | 02-Dec-2006 16:59:30 | 47.1 | 3.3 | 435.300.752 | 0 |
| AO-51 | 02-Dec-2006 17:00:00 | 42.3 | 3.4 | 435.299.945 | 0 |
| AO-51 | 02-Dec-2006 17:00:30 | 37.5 | 3.3 | 435.299.138 | 0 |
| AO-51 | 02-Dec-2006 17:01:00 | 32.8 | 3.1 | 435.298.348 | 0 |
| AO-51 | 02-Dec-2006 17:01:30 | 28.2 | 2.7 | 435.297.587 | 0 |
| AO-51 | 02-Dec-2006 17:02:00 | 23.7 | 2.1 | 435.296.868 | 0 |
| AO-51 | 02-Dec-2006 17:02:30 | 19.5 | 1.5 | 435.296.199 | 0 |
| AO-51 | 02-Dec-2006 17:03:00 | 15.5 | 0.7 | 435.295.585 | 0 |
| AO-51 | 02-Dec-2006 17:03:30 | 11.7 | -0.2 | 435.295.028 | 0 |
| AO-51 | 02-Dec-2006 17:04:00 | 8.2 | -1.1 | 435.294.529 | 0 |
In the described way, the number of "necessary hands" is again reduced a bit - satellite operators know what it's about, HI. The description of what Ham Radio Deluxe offers alone would be enough for several articles. But try what I'm going to write for yourself. You can find the HamRadio Deluxe program on the site .: HERE .: