Successful first tests of the UNITEC-1 receiver setup

Today we carried out the first test campaign of the 5.6-5.9 GHz receiver setup consisting of the KU LNC 5659 C PRO low noise down-converter, USRP with WBX daughterboard and some GNU Radio software. Our plan was to test the receiver using the 5.76093 GHz signal from the OZ7IGY beacon. The results are as follows:

  1. Once we figured out to correctly apply DC voltage to the LNC via the bias tee we saw clearly the noise floor rising so the LNC was very much alive.
  2. We could clearly hear a signal sent over the from a 5.8 GHz signal generator. Unfortunately, the signal generator was not calibrated to perform any quantitive measurements.
  3. We could not receive the 5760.930 MHz signal from the OZ7IGY beacon. This was not surprising since we do not do not have very clear line of sight in the direction of OZ7IGY from the OZ7SAT HQ – not inside the building. There were, however, a few seconds where we could clearly hear OZ7IGY. This time coincided with an airplane passing by so it was obviously a reflection off the plane we received! A very funny coincidence.

The next step with respect to OZ7IGY will be to go up to the roof and try from there. We decided to wait with that till next week because it was already dark and rather cold.

We spent the remaining time on performing some receiver measurements on the WBX transceiver board for the USRP. You can read about them here.

Author: Alexandru Csete

Embedded software engineer in the satcom industry during the day. Radio amateur and SDR hacker during the night.