A few words of conversation can also be picked up on the VHF transmission channel. For launches from Baikonur, the majority of Europe has to wait about 4.5 hours before signals can be intercepted on rev 3. Eastern Europe sees a low elevation pass on rev 2 but interception of signals depends on co-visibility with Moscow.

During the ascent and an initial period in orbit, the Space Shuttle uses a straightforward VHF air-ground system for the crew to communicate with Houston. It is in the military airband, for Europe at least, and is amplitude modulated (AM). Once initial checks are out of the way and onboard systems start to be activated, the shuttle switches to S-band.

There is a ground station near Madrid, Spain and it is usually possible to pick up a few terse words as the orbiter passes by on Rev 0. The content is quite often a reference to a pre-printed checklist. Occasionally there can be heard mention of an umbilical door closing. This is is a door covering one of the apertures through which a propellant line passed while the orbiter and external tank were still connected.

The shuttle switches back to VHF prior to re-entry. Occasional bursts of unmodulated carrier and voice have been noted from Europe on the final orbit.

As well as the voice channel, Soyuz transmits at two other frequencies. All three transmissions are relatively easy to receive. The telescopic aerial supplied with most receivers will normally be sufficient but will require some 'waving around' to find the best direction to point it.

Soyuz voice is frquency modulated with a deviation around 30-40 kHz. On most receivers the narrow FM setting will produce a result but the bandwidth is slightly narrower than ideal. Unfortunately, the FM setting is often a little too wide and the voice can get lost in the background hiss. The VHF frequency can be detected in both FM and AM modes. The UHF frequency above 900 MHz needs the receiver set to CW and manifests itself as a rapidly falling tone.

On launch day, eastern Europe gets a low elevation pass on rev 2 - about three hours after launch. Rev 3 brings a pass that can be detected just about anywhere as long as Soyuz is in line of sight from the ground station at Bear Lake near Moscow. Sometimes, signals appear a little earlier than expected so it might be indicative of working with the ground station near St Pertersburgh.

The map above shows the tracks of Revs 3, 4 and 5 of a newly-launched Soyuz. Soyuz moves from west to east and successive orbital tracks migrate to the west as the Earth rotates beneath ot orbit.

Rev 4 and Rev 5 usually yield good signals at 166 and 922 MHz. One or both of Revs 4 and 5 can be detected as Soyuz rises in the west. This is because of an orbit adjustment to move Soyuz from its initial low, circular orbit to its transfer orbit for rendezvous with the ISS. The adjustment takes place out of sight of ground stations so the transmitter is left on to ensure the craft can be detected in the event of the manoeuvre going awry.

One point to note about Rev 4 is that, going right back to days when Soyuz used to transmit at HF, closest approach to the UK as measured from the Doppler shift comes at 6hr 6m after launch (+/- 1 min).

Rev 5 is the final chance for voice on day one. It is a low elevation pass as seen from Moscow but, being at a strategic point in the mission, voice communication is important. Equivalent passes on other days in the flight do not usually produce transmissions of any kind.

Launches of Progress re-supply spacecraft occur from Baikonur. The first few passes mirror those of Soyuz and the transmission pattern is similar, with the exception of the voice.

The plot below was made in real time and shows the Doppler curve from the 922 MHz transmission by Progress M-63.