by Robert Brand
In my limited research of OTC stuff in the country’s archives, I came across this item:
“H5684 audio recording framed sputnik signals paper tape wood glass recording the signals from ussr sputnik satellite received at Bringelly Overseas Telecommunications Commission“
It seems that OTC staff both received and recorded this event. The recording was done on paper tape and I believe that in the picture, the tape is folded into an inverted “V”. Does anyone know about this item in the archives and can add some detail to this? The year was 1957.
It looks like this was a gift to the Powerhouse Museum. I later located this document:
“Audio recording, framed, ‘Sputnik signals’, paper tape / wood / glass, recording the signals from USSR ‘Sputnik’ satellite received at Bringelly Overseas Telecommunications Commission (OTC) radio receiving station, NSW, Australia, 1957 (OS)
Section of tape recording of the signals from the Russian man-made satellite “Sputnik” as received at Bringelly international receiving station (SB).”
Radio Systems (From Wikipedia):
The power supply, with a mass of 51 kg (110 lb), was in the shape of an octagonal nut with the radio transmitter in its hole. It consisted of three silver-zinc batteries, developed at the All-Union Research Institute of Current Sources (VNIIT) under the leadership of N. S. Lidorenko. Two of them powered the radio transmitter and one powered the temperature regulation system. They were expected to fade out in two weeks, but ended up working for 22 days. The power supply was turned on automatically at the moment of the satellite’s separation from the second stage of the rocket.
The satellite had a one-watt, 3.5 kg (7.7 lb) radio transmitting unit inside, developed by V. I. Lappo from NII-885, that worked on two frequencies, 20.005 and 40.002 MHz. Signals on the first frequency were transmitted in 0.3 sec pulses (under normal temperature and pressure conditions on-board), with pauses of the same duration filled by pulses on the second frequency. Analysis of the radio signals was used to gather information about the electron density of the ionosphere. Temperature and pressure were encoded in the duration of radio beeps, which additionally indicated that the satellite had not been punctured by a meteorite. A temperature regulation system contained a fan, a dual thermal switch, and a control thermal switch. If the temperature inside the satellite exceeded 36 °C (97 °F) the fan was turned on and when it fell below 20 °C (68 °F) the fan was turned off by the dual thermal switch. If the temperature exceeded 50 °C (122 °F) or fell below 0 °C (32 °F), another control thermal switch was activated, changing the duration of the radio signal pulses. Sputnik 1 was filled with dry nitrogen, pressurized to 1.3 atm. For the pressure control the satellite had a barometric switch, activated when the pressure inside the satellite fell below 0.35 kg/cm2 (5.0 psi), changing the duration of radio signal impulse.