Cambridge Amateur Radio Astronomers - Proposed Letter of Intent

Phase One

Primary Goals :

Secondary Goals :

Methodology

General Hardware :

We have obtained a Focus box and are making the following modifications:

Once the Focus box modifications are complete, the unit can be tested and refitted to the 18m dish at a time convenient with MRAO. There are two RF feeds from the focus box. One will pass 408/432MHz clockwise signals and the other will pass 408/432MHz anticlockwise signals together with 1407MHz signals.

Either 408/432MHz or 1420MHz signals are converted to IF and the signal levels are detected using existing MRAO equipment in the equipment room.  The IF and detection equipment will be used without modification unless it is found to be faulty. 

System testing

Using either the Sun or the moon as a signal source, the system noise temperature and aerial responses can the estimated.

Pulsar measurements

Using 408MHz at either polarisation, the detected  power level is  sampled using a PC and A/D converter at a suitable rate above the Nyquist frequency for the Pulsar being observed. The observation will continue for the time that the Pulsar is above the horizon, the Telescope being set to track . Once  data has been collected for a number of hours,  a spectral analysis is performed and the Pulsar frequency should be observable as a peak above the noise.   

Moon bounce

A 433MHz signal will be radiated from a 4m dish located about 6 miles from MRAO. This signal will be picked up at MRAO directly as well as from the moon. The time difference between the arrival of the two signals can be measured using a Digital Storage Oscilloscope. 

Hydrogen Line

The spectrum and sky map of the Hydrogen line will be investigated at 1420MHz and below. 

Software

Dish pointing software

There are two threads for suitable dish positioning software:

Peter DS 

This program will run on the existing PC in the control room, and will provide positioning information to the Telescope operators. 

Matthew/Andy/Nick

This will be an implementation of a queuing system for scheduling observations, giving pedantic instructions to an operator.

Data processing software

The control room under the Telescope has a PC with A/D converter card suitable for any data processing requirements for Phase 1.

Milestones:

Acquisition of dual-band Focus Box

Bernie, PeterDS

Complete

Modification of Focus Box aerial system

Bernie

Complete

Testing of Focus box aerial system

Bernie PhilR

End Feb

Replacement of 408MHz LNAs

PeterK

Early-March

Replacement of 1420MHz LNA

Jenny

End-Feb

Test and Integration of Focus Box

Jenny/Bernie/PeterK/PhilR

Mid-End-March

Re-mounting Focus Box

MRAO staff

End-March

DOS aerial positioning software

PeterDS

End-March

Linux aerial positioning software *

Matthew/Nick/Andy

End-March

Web Interface *

Jennifer/Nick

End-March

Data Acquisition software

PeterDS

End-March

Data processing software

T.B.D.

End-March

Initial system testing

All

Early-April

OMT First Light ( RF )

All

Mid-April

Publish results on Web

T.B.D.

End-April

* = non-critical