RadioAstron Monthly Notices

December 2003 - March 2004

 

1. Radio astronomical tests of the engineering model of the space radio telescope (SRT) were completed in Pushchino - see Results. The main targets of SRT testing - antenna parameters (effective area and beam shape) were measured at all frequency ranges by the boresighting on bright radio sources, and were found corresponding to the technical requirements. Interferometric observations were also conducted between 22-m radio telescope and the SRT at 6 and 1.35 cm with the baseline of about 500 m. At both frequencies fringes were detected using ASC hard disc recorder and correlator. The engineering model of the SRT has been returned to LA.

 

2. Upgrade of the spacecraft bus Spectr-R was initiated by LA with conservation of launch date (March 2006). It is directed to use modern achievements in vacuum operating technology of some electronic systems, which will reduce total weight and power consumption and will increase the operation time to 5 years and reliability.

 

3. Monitoring of the development of the upgrade on-board 1.35-cm receiver (R-SRT-1.35 cm):
1. Engineering model of the power supply unit has been manufactured;
2. Laboratory model of the receiver has been manufactured and tested;
3. Test set for the receiver was also manufactured and tested.

 

4. Monitoring of the development of the on-board formatter:
1. The set of mechanical details and components has been manufactured

for three Formatters - ground test model and two flight models;

2. Power supply unit was assembled and tested for ground test model;
3. Formatter ground test program was issued.

 

5. New 18-cm receiver was installed at the 64-m radio telescope in Kalyazin; it has two polarization channels (RCP and LCP). With this receiver the measurements of Tsys and Aeff were performed (Tsys=60 K, Aeff=1600 square meters). Test observations of the OH maser emission (1665/1667 MHz) were conducted using new autocorrelation spectrometer.

 

6. Teleconference was held on February 26 with discussions on the topics related with Pushchino tests. No new action items were formulated.

 

Appendix - the list of used acronyms

 

 

ASC Astro Space Center of Lebedev Physical Instutute

Cold Plate cooled LNAs and antenna feed

DC hermetic device container (part of payload); it contains Formatter, Rb oscillators,

synthesizer, control unit and is placed under dish

DM Device Module = DC + H-maser

EGSE Electronic Ground Support Equipment

Electronic Complex - all SRT electronics

 

EM Engineering Model

FC Focal Container - hermetic package with the scientific payload; it contains receivers,

microwave synthesizer, control unit and is placed in focal site of dish

FM Focal Module = Focal Container+Cold Plate

LA Lavochkin Association

OHCFS-SRT Space Radio Telescope On-board Heterodyne and Clock Frequency Synthesizer set

OHFS-SRT Space Radio Telescope On-board Hydrogen Frequency Standard

ORFS-SRT Space Radio Telescope On-board Rubidium Frequency Standard

Service Module, Spacecraft bus - spacecraft itself (without payload).

SRT Space Radio Telescope (all scientific payload including 10-m dish)

TMS Spacecraft Telemetry System (technical)

TVT Thermo-Vacuum Tests

VIRK Scientific high rate (up to 2x72 Mbit/s) radio complex, including transponder

ZBIT Zero Baseline Interferometer Tests (ZBIT)