[jamsat-news:696] ANS-323 SPECIAL BULLETIN

[Keith Baker <kb1sf@compuserve.com>]

SB SAT @ AMSAT  $ANS-323.01
RS-17 TELEMETRY SURVEY (SPECIAL BULLETIN)

HR AMSAT NEWS SERVICE BULLETIN 323.01 FROM AMSAT HQ
SILVER SPRING, MD, NOVEMBER 19, 1997
TO ALL RADIO AMATEURS BT
BID: $ANS-323.01

AMSAT-France is asking radio amateurs around the world to help 
collect telemetry from RS-17 on Saturday, November 22, and 
Sunday, November 23, 1997.

This data will help AMSAT-France in verifying the parameters of 
the thermal model of the microsat that was computed before the 
launch. This information will also be used in the design of the 
AMSAT-France microsat project, named Maelle.

The internal temperature of the satellite can be measured from 
the tone of  the "beep-beep" sound transmitted twice per second. 
In order to get precise measurements, the frequency of the tone 
should be measured to an accuracy of +/- 1 Hz.

Bernard Pidoux, F6BVP, of AMSAT-France suggests directly 
recording the beacon using the tape recorder function of the 
Windows-95 program (through a sound card) connected to the audio 
output of a VHF receiver seems to work best. The receiver should 
be set in FM mode on 145.820 mHz, compensating for doppler effect 
during the satellite pass.  The audio should also be unsquelched 
during the recording. 

In order to keep the data to a manageable level, numeric 
samples should be performed at 8 kHz with 8 bits precision 
in mono mode. One or two seconds of beacon recording with a 
strong signal are needed. Save your .WAV file and note the date 
and precise UTC time of capture. If you have a program than can 
accurately measure the audio frequency, please also provide the
value of the tone in Hz. If you cannot measure the audio 
frequency, just send the WAV file in ZIP format. The size should
not be more than 16 kb (1 or 2 seconds at 8 kHz, 8 bit samples
in mono). 

Reports can be sent by packet radio to:

<f6bvp@f6bvp.frpa.fra.eu>

or by Internet e-mail to

<f6bvp@amsat.org>.

At this time AMSAT-France has received reports of the tone 
frequency ranging from 1255 to 1300 Hz (corresponding to 
temperatures between 23 an 33 degrees Celsius).

[ANS thanks Bernard Pidoux, F6BVP, for the information that went
into this bulletin item.] 

/EX