RADIO-M1    AMSAT-DL/AMSAT-U joint Project
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Linear Transponders and Rudak-II sheet
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RUDAK II  (2nd Generation)  is a part of the Russian amateur radio transponder
"RADIO-M1". "M"  refers to Molodechno, White Russia, USSR. RUDAK is the German
abbreviation  for   Regenerative  Transponder   for  Digital   Amateur   Radio
Communications. The  transponder is  a  joint  project  of  AMSAT-U-ORBITA  in
Molodechno, AMSAT-U-SPUTNIK group of the Adventure Club  in Moscow and
AMSAT-DL/RUDAK group in Marburg, Munich and Hannover.

Launch:       June, 1990 from Plesetsk, USSR with PROTON rocket

Satellite:   "Subtenant" to GEOS, a Russian geological research satellite.

Orbit:       Circular orbit at 1000 Km altitude and 83 deg. inclination.
             Orbital period=105 minutes.

Amateur Radio Payload

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  Linear Transponder 1:

  Uplink:    435.102 - 435.022 MHz (80 KHz)

  Downlink:  145.852 - 145.932 MHz (inverted)
  
  Output power: 10 Watts maximum.
     
  Beacon CW telemetry (8 parameters):  145.822 MHz   0.2 Watts
  
  Beacon digital telemetry (30 parameters) 1100 bps PSK
  R+Scrambler  2 kHz deviation  145.952 MHz  0.4 Watts
     

  Regenerative Transponder RUDAK-2:

Two  onboard computers  with IPS  operating system  for packet radio
(AX.25) (Mailbox, telecommunications experiment with digital signal processing
up to nearly 20 KHz, etc.) 1 MByte RAM disk. Four separate uplink channels.

Gain of satellite RX and TX antennas: 2.3 dBi each (dipoles)

Input sensitivity: < -125 dBm (435 MHz) for a C/No of 45 dBHz

SAT-RX-1:    435.016 MHz +-10 KHz  1200 bps, FSK, NRZIC/Biphase-M (JAS, PACSAT)

SAT-RX-2:    435.155 MHz +-10 KHz  (AFC) 2400 bps, BPSK, Biphase-S

SAT-RX-3a:   435.193 MHz +-10 KHz  (AFC) 4800 bps, RSM, NRZIC/Biphase-M

SAT-RX-3b:   435.193 MHz +-10 KHz  (AFC) 9600 bps, RSM, NRZI (NRZ-S) +
                                   Scrambler

SAT-RX-4:    435.041 MHz +-10 KHz  (digital AFC) RX for RTX-DSP experiments

     Output signals  of RX-4  are the In-phase and Quadrature components, I(t)
     and Q(t),  which are sent to the DSP RTX immediately after analog/digital
     conversion with  8 bit resolution. This supports various modulation modes
     depending on the software. All other receivers provide data (D) and clock
     (C) at their outputs.

The downlink can be switched to the following operating modes:

Transmit frequency:  145.983 MHz

Mode 1:   1200 bps, BPSK, NRZI (NRZ-S) (like FO-20)
Mode 2:    400 bps, BPSK, Biphase-S (AMSAT mode for OSCAR-13 beacon)
Mode 3:   2400 bps, BPSK, Biphase-S (planned for OSCAR-13)
Mode 4:   4800 bps,  RSM, NRZIC (Biphase-M) (like 4800 bps uplink)
Mode 5:   9600 bps,  RSM, NRZI (NRZ-S) + Scrambler (like 9600 bps uplink)
Mode 6:   CW keying (only for special events)
Mode 7:   FSK (F1 or F2B), e.g. RTTY, SSTV, FAX, etc (only for special events)
Mode 8:   FM modulated by D/A signals from DSP-RISC processor (e.g. speech)

Power consumption:  14V @ 350 mA (max) = 4.9 W;
                    Standby: 80 mA (RUDAK without power amplifier)

Mass:               6.2 KG

Dimensions:         230 x 320 x 120 mm3
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  Linear Transponder 2:
     
  Uplink:      435.123 - 435.043 MHz (80 KHz)
     
  Downlink:    145.866 - 145.946 MHz
  
  Output power:  10 Watts maximum
     
  Beacon CW telemetry (8 parameters):  145.948 MHz  0.2 Watts
     
  Beacon digital telemetry (30 parameters) 1100 bps PSK
  R+Scrambler 2 KHz deviation  145.838 MHz  0.4 Watts.
     
  Beacon digital telemetry (30 parameters) 1100 bps PSK
  R+Scrambler 2 KHz deviation  145.800 MHz  2 Watts

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Total power consuption: 40 Watts (maximum)

Total mass:  22 Kg
     
Total dimensions: 480 x 400 x 300 mm^3
     
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                   Compiled by DB2OS RC2CA UA3CR    10apr1990