Message 15/504 agg@jb.man.ac.uk                   Oct 17, 2000 01:50:57 am
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Date: Tue, 17 Oct 2000 01:50:57 -0700 (PDT)
To: evntech@jb.man.ac.uk
Subject: EVNtech: Jodrell Bank VLBI Status Report
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Sender: owner-evntech@jb.man.ac.uk
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Jodrell Bank Observatory

VLBI Status Report - October 2000

(1) Mk4 Terminal:

The low gain problem in VC4 has become critical and has
been 'fixed' by exchanging filter boards and VC with VC15.
The faulty amplifier is obsolete but a replacement is being
located. We are preparing to order the new MK4 decoder.

(2) VLBA Terminal:

We discoverd the headstack had worked loose due to stripped
threads in the alloy block. These are now replaced with the
newer, ten-degree-slope type, in this recorder.

The VIV head upgrade assembly is complete and should have    
been installed by the TOG meeting. There are problems working
out the patch-panel wiring.

Despite substantial checking of the RF sytems we still seem
to have difficulties with the 28MHz SP setup. A test to find
the problem will be made locally.

(3) Time and Frequency:

No significant problems, although we have some difficulties with
clock modelling in the PC-FS. A new TAC GPS receiver with the
TAC-Plus software and an NT PC have been purchased as a move
toward automated clock logging. We are beginning to consider
when/if the maser may need replacement.

(4) RF Systems:

No immediate changes, although a new 6GHz cooled Rx is nearing
completion. Work continues on integrating the various Jodrell
observing programs, and the MK2 telescope carousel is now
fully operational. Works starts on the Lovell upgrade next year,
allowing 5GHz observing.

(5) Operations:

No significant operations issues at present. Some tape shipments
were delayed in the September session due to fuel shortages!

Paul Burgess, Alastair Gunn, Simon Garrington