Why is 2 m soooooooo difficult if the receiver is not deaf?
There are several reasons for this perception. Firstly, it is believed that the antenna may have been damaged. But there are other reasons too: the 2m uplink is not always on – it is used quite often for command functions by the team controlling the spacecraft. Also, The V-Rx and the U-Rx cannot be active at the same time – they are both controlled by a single bit, telemetry byte #1CA. There have been reports of interference to the 2m uplink from various terrestrial sources, including pirates and atmospheric noise. Finally, 2m beams giving the same gain as 70cm beams are physically much larger, and so less common. Thus many people are attempting 2m up-links at much lower signal levels than on 70cm. In addition, many people use 2m as their down-converter IF, so de-sensing of their receiver can be a problem when up-linking on 2m.
