_                    
                                                         |_|                   
      V   V   SSSS   OOO   PPPP                 \__      |_|      __/          
      V   V  S      O   O  P   P                   --____/ \____--             
      V   V   SSS   O   O  PPPP                    _ _ _ --- _ _ _             
       V V       S  O   O  P                      |_|_|_|  @|_|_|_|            
        V    SSSS    OOO   P                             o-o                   
                                                          /                    
      ***  N    E    W    S  ***                        <)                     
 

VSOP CORRELATOR

The VSOP correlator is now installed at the National Astronomical Observatory in Mitaka. Earlier this week the hardware for the FX-design, ten-station correlator was moved from the Fujitsu factory to the NAO, where it now sits in the new correlator building. It was reported in VSOP News no.11 that seven playback units had been constructed (and these are now in Mitaka) -- the good news is that since then funding has been obtained for the remaining three units. Also installed this last week were the two VLBA playback units and one S2 unit which will used for translating tapes from these formats to VSOP format prior to correlation. As the name suggests, the VSOP correlator has been designed with the correlation of Space VLBI data in mind, and it features large delay and delay-rate search windows. Hardware integration of the correlator is expected to take about two months, with software development and testing taking a further five or six months. First fringes will hopefully be seen in several months time, with routine operation starting early next year.

NEAR REAL TIME FRINGE DETECTOR

VSOG staff visited the OKI factory recently to check on the construction of the prototype model NRT Fringe Detector, and found that everything was progressing smoothly. The prototype model is designed to have 256 lags with a delay rate window of 10 Hz. The final NRTFD, which is based on a custom designed chip, will have a maximum of 1024 lags, or a maximum delay rate 40 Hz: the maximum of one can only be chosen by reducing the range of the other. The NRTFD will be installed at the Usuda Tracking Station, and used some of the time for real time auto-correlation of data down-linked from the VSOP satellite. For observations in which the Usuda 64m telescope is being used, the NRTFD will be used to check at the end of the observation for fringes on the Usuda-Spacecraft baseline. The NRTFD is expected to be completed by August this year.

THE HAZARDS OF COMMUTING

People driving along a certain road in Socorro reportedly encounter a sign saying "Beware! Telescopes crossing"... Visitors to the Australia Telescope Compact Array are warned in advance to look out for kangaroos... Nobeyama is just one of many telescope sites which can have access blocked by snow. However, with winter nearing its end, people at ISAS were a little surprised when Hirax arrived one morning recently and announced gravely that Route 16 had been very slippery. It turns out that icy conditions were not the problem at all; due to a truck losing some of its cargo, the road was indeed covered in slippers!! Appropriate pun-ishment for Hirax is still being considered...

 
 
       Editors: Phil Edwards and Hirax Hirabayashi