ISSCOM 8 August 2003 (037)

Radiotraffic VHF-1: During the period in which the pass of the ISS over the Netherlands occurred during the night hours, I did not pick up any voice communications via this channel. After 21.07.03 the passes gradually took place during the evening hours and now and then VHF-1 is in use for short comm. sessions to discuss technical and operational matters.
Meanwhile it is quite clear that the VHF-1 does no longer act as the primary channel for radio communications to and from the Russian Service Module of the ISS, Zvezda. In stead of VHF-1 the Russians use the system Regul. Originally this system was developed to be used via the Russian geostationary satellites of the Altair/Luch series. The communication system in the Zvezda still has the means for comm. via such geostationary satellites (SR-s), so the Russians had to choose an alternative procedure for using Regul. The frequencies for Regul to reach the SR-s with the antenna OHA (high gain antenna on the Zvezda were 922.760 and 768.975 mc. (resp. out and in). Via the antenna feeder system the transceiver of Regul can be connected with 2 antennas on the Assembly compartments (WA1 and 2) and 2 antannas (WA3 and 4) at the ends of the Solar Batteries of the Zvezda. In this way Regul can communicate with Russian tracking stations (NIPs). It is quite possible that Regul already has a higher priority than VHF-1. Additionally the Russians in Zvezda can communicate via the intercom with the American segment with American systems, for instance the S-band. More and more the Russians use this possibility for communications with both MCC-s.
Data transmissions: Recently Packet Radio was in use for the transfer of data via the VHF-channels 1 and 2. This traffic can now be handled via Regul. There also is the American Ku-band with a higher capacity than Regul. The major bulk of the radiograms, operational documentation, videolinks, etc. goes via the Ku-band.
Reception Regul transmissions: For me in The Hague it is impossible to monitor Regul transmissions via 922.760 mc due to the strong interference of a local data transmitter nearby -the remote cardio watch of a local hospital.
Recently I was in Starcity (TsPK) near Moscow for a short stayn. I attended some private lessons about communication systems (for the Soyuz-TMA -system Rassvet-M and for the ISS Russian segment -Voskhod-M). I also got a long extensive explanation about the electronic approach system Kurs.

Chris van den Berg, NL-9165/A-UK3202