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Can my station measure the QO-100 NB transponder LO stability?

Following a long discussion with Bernd Zoelgert DL2BZ about the frequency stability of the local oscillator of the QO-100 narrowband transponder, I have decided to try to measure the Allan deviation of the transponder. The focus here is on short-term stability, so we are concerned with observation intervals around $$\tau = 1 \mathrm{s}$$. Of course,… Continue reading Can my station measure the QO-100 NB transponder LO stability?

Software for my QO-100 groundstation

You may have heard about my groundstation for QO-100 (Es’hail-2), which is based on a BeagleBone black and a LimeSDR Mini. A description of this station appeared in a LimeSDR field report. However, I haven’t spoken in detail about the software yet, since I was testing various things and using a makeshift setup until I… Continue reading Software for my QO-100 groundstation

Transmitting through QO-100 with the LimeNET Micro and LimeRFE

A couple weeks ago, I did a demo where I showed the LimeRFE radio frequency frontend being used as an HF power amplifier to transmit WSPR in the 10m band. Another demo I wanted to do was to show the LimeNET Micro and LimeRFE as a standalone 2.4GHz transmitter for the QO-100 Amateur radio geostationary… Continue reading Transmitting through QO-100 with the LimeNET Micro and LimeRFE

Second Moon observation with my QO-100 station.

In May 25, the Moon passed through the beam of my QO-100 groundstation and I took the opportunity to measure the Moon noise and receive the Moonbounce 10GHz beacon DL0SHF. A few days ago, in July 22, the Moon passed again through the beam of the dish. This is interesting because, in contrast to the… Continue reading Second Moon observation with my QO-100 station.

First Moon observation with my QO-100 station

A month ago, I spoke about planning the passes of the Moon through the beam of my QO-100 station. These give an occasion to observe the Moon without moving a dish that is pointing to Es’hail 2. The next opportunity after writing that post was on May 16 at 20:16 UTC. Since I wasn’t going… Continue reading First Moon observation with my QO-100 station

Planning Moon observations with my QO-100 station

There is a saying that goes like “even a broken clock is right twice a day”. In the same spirit, even a QO-100 station, which is installed with a fixed dish aiming to Es’hail 2, can sometimes be used for observing the Moon, as it happens to pass in front of the beam. My station… Continue reading Planning Moon observations with my QO-100 station

The Amateur transponders of Es’hail 2 have their downlink in the 10GHz Amateur band. Even though the path to the satellite through the atmosphere is rather short, in extreme weather conditions it is possible to observe a small amount of fading in the signal. Two days ago there was intense rain over Madrid. As I’m… Continue reading Rain fade in the QO-100 downlink

QO-100 beacon FEC decoder

Since the BPSK beacon on the QO-100 narrowband transponder was first activated, I had thought that it only transmitted messages using the AO-40 uncoded protocol. However, a Twitter conversation a few days ago with Rob Janssen PE1CHL convinced me that FEC messages might be sent in between uncoded messages. The AO-40 FEC protocol used a… Continue reading QO-100 beacon FEC decoder

Weekend maintenance to QO-100 NB beacons

This weekend, the beacons of the Es’hail 2 narrowband transponder have undergone maintenance. The beacons have been off for several periods of a few hours on Friday and Saturday. After the maintenance, there are two main changes: the phase noise of the beacons has been fixed, and the beacons are now approximately 3dB stronger. Since… Continue reading Weekend maintenance to QO-100 NB beacons

Measuring QO-100 beacons frequency

Continuing with my frequency measurements of Es’hail 2, I have now been measuring the frequency of the beacons of the QO-100 narrowband transponder for several days. The main goal of these frequency measurements is to use Doppler to study the orbit of Es’hail 2. Previously, I had been doing frequency measurements on the engineering beacons… Continue reading Measuring QO-100 beacons frequency