The following people met at the control building of the 1 mile
telescope at Lord's Bridge at 14:00 on Sunday the 20th November 1999.
The state of the equipment
Peter explained the operation of the equipment in the control room,
and gave a summary of its current state of repair. This can be
summarised as follows :
The dish steering equipment consisting of positional sensors,
positioning motors and control equipment is working for the dish
mounted adjacent to the control building. Eventually the position
encoders and possibly the motor switching will have to be replaced,
together with the steering control processor.
A suitable sidereal clock source accurate to a number of ms will have
to be obtained. Two possibilities are GPS and NTP ( network time
protocol ) . The dish surface is accurate enough for work up to
1407MHz, and probably up to 5GHz.
The state of the dish feed and LNA is unknown, this is to be
investigated. There was a discussion about mixing down to IF at the
dish feed or mixing in the control room. For an interferometer, mixing
at each dish feed would be ideal. However, for the single dish
configuration, mixing in the control room gives us more flexibility.
The IF unit ( at 45MHz, 4MHz BW ) is believed to be working. It can
output a DC signal proportional to the received noise power. There is
a working PC loaded with DOS and an A/D converter card that can be
used for logging. If this computer is to be interrogated remotely,
then another operating system such as Linux might need to be
installed. The capabilities of this PC ( HD space, RAM, CPU ) should
be assessed. Note that it might be difficult to drive the existing
A/D converter card under Linux.
The state of the other dishes is unknown.
Phase 1 It was decided that Phase 1 should be quickly
attainable and therefore the existing equipment should be used where
The aim of this phase is to observe the radio source in the crab
nebula at 408MHz. This will be automatically tracked with the existing
Investigate the state of the existing LNA - Peter and Guy
Find diagrams/specifications for system - Peter and Guy
Acquire spare LNA for Bernie - Peter
Set up mailing list for group - Andy
Investigate domain name for group - Andy
Investigate Internet access from control room - Peter
Access to site - keys, introductions - Peter
Web site design - Matthew