Kodiak Tracking Station's First Pass Supports
(The Earliest Years, Corona)

Marv Sumner and Bob Siptrott
Technical Material for this article was provided by two civilian employees. Both were stationed at the Kodiak Tracking Station (KTS.) during the "Earliest Years."

The earliest configuration of the Kodiak Tracking Station, call sign (KODI), had two antennas. A VERLORT 3-Pulse tracking and commanding radar and a Tri-Helix, telemetry receiving antenna. The offsite communications was 100 word per-minute teletype (TTY) and analog voice. No other communications! (A High Frequency (HF) radio system was installed for back-up voice and data, but never used)

TTY messages from the Satellite Test Center, Sunnyvale, California. (STC) as it was known then, now, Onizuka Air Force Station, Sunnyvale, California, would tell us the launch and pass (orbit) schedules. After the pass KODI then would TTY the pass history and telemetry readouts to the STC. All other pass related readouts were relayed to the STC by real-time voice.

Security Note: The Russian fishing trawlers were abundant during launch time. They were about 13 miles due east of the site, probably listening to all our voice and commanding. The TTY was encrypted, but all else was in the clear. Sometimes we thought the Russians knew as much as we did, about our schedule. Sometimes they left when a launch was scrubbed, before we were aware of the scrub.

Our VERLORT (Very Long Range Tracking) radar transmitted 3 pulses during each PRF. A main pulse, a command pulse and an execute pulse. There were two forms of commanding, initially only analog, later a digital mode came along. In analog commanding, the time position of the middle pulse was varied at a sinusoidal rate. There were four (4) frequencies transmitted in pairs for a possible list of six commands, later expanded to 15 commands. Digital commands had three discrete time slots sitting between the main pulse and the execute pulse - A slot each for "ones," "zeros" and "Ss." If ones and zeros were not going out, the "Ss" kept the system in sync and the radar average power constant. Analog commanding instructions came to us by real time voice, and digital commands came prepass as TTY punched paper tape.

The radar could auto track the satellite's angles and measure range to deliver tracking data. The tracking data was displayed in the KTS site's control room on a large X - Y plotter with pre-printed paper maps. The pass progress was described verbally over the net to the STC in real time, and the maps were mailed to the STC daily.

The telemetry antenna and it's equipment van were located on a hill (called T-Hill or Read Out Ridge), away from the radar and the TTY equipment. The van had receivers, demodulators, tape recorders, decommutators and displays. All data leaving T-Hill was either on the voice line or in the mail-bag.

After a pass support, the magnetic tapes, strip chart recordings tracking map and handwritten data sheets were wrapped and addressed for mailing and taken to the site's mailroom. Lists of special readouts were taken to the TTY operator and hand typed for postpass transmission to the STC.

There was a third antenna which was a single whip on the roof of the van receiving an unmodulated RF carrier from the satellite at 216 MHz and measuring the one way Doppler Data, The Doppler receiver's output was a punched paper tape taken to the TTY room and transmitted to the STC.

Early satellites lasted only one day (if they got into orbit at all) were recovered the next day over the pacific ocean. Later, of course they lasted longer and now years.


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