2012 /13 Monmouth Science Imitative Project 11Ghz Small Radio Telescope Electronics developed during 2012 Commercial satellite TV equipment modified Measurements made in 2013

Post detector amplifier Digitiser Lap top computer Main component are: 1.2m dish Low noise receiver Detector unit Post detector amplifier Digitiser Lap top computer Detector Post detector amplifier Digitiser Low Noise Receiver 1.2m diameter offset Parabolic dish

Students built and tested the post detector electronics It provides signal offset Amplification Filtering

Data is generated by driving the antenna in azimuth and recording the digitised received signal The dish elevation is raised and the scan repeated This produces a two dimensional array of numbers False colour images can be generated from this data All hot bodies (ie T > 00 K) emit radiation This extends into microwave region The ground is ‘hot’ at microwave frequencies This can be measured with the sensitive 11GHz ‘Radiometer’ Signal level from hot bodies is greatest toward optical frequencies Plank’s Law microwaves

11GHz Radio Data Map 13/11/2013 Values represent intensity of Elevation Angle Elevation Angle 11GHz Radio Data Map 13/11/2013 Azimuth Bearing Azimuth Bearing Values represent intensity of received signal

The first step of data reduction is to plot each azimuth scan This can be done in EXCEL Shows some large spikes These are satellites Also shows ground features Excel Plot of 11GHz Azimuth Scans for different Elevations – Monmouth School 13/11/2013 Signal Intensity (Volts) 150E 120E 00 100 Azimuth Bearing 90E 200 Elevation Angle 300 60E 400 30E 500 S 30W

Excel Plot of 11GHz Azimuth Scans for different Elevations - Monmouth School 13/11/2013 European Satellites Building Signal Intensity (Volts) High Ground Ground temperature Building Atlantic Satellites 00 100 30W S 30E 60E 90E 120E 150E 200 300 Azimuth Bearing Elevation Angle 400 500

The 2D data map can be converted to a visual image Used ‘Stanford Chart’ software Shows ‘cold’ blue sky ‘Hot’ satellites Ground temperature

Radio image of Sky at 11 GHz 11GHz Radio Map of Sky South of Monmouth 13/11/2013 500 ‘Cold Sky’ 450 400 Atlantic Satellites 350 European Satellites 300 250 Elevation 200 Satellite Building Building 100 High Ground 150 50 00 Time 15:35hrs GMT, Dish No 1, Automatic Azimuth Drive, 50 elevation steps,ADC11 Data Logger, Stanford Chart Mapping 150E 140E 130E 120E 110E 100E 90E 80E 70E 60E 50E 40E 30E 20E 10E S 10W 20W 30W Azimuth Bearing

Graphic showing area scanned by antenna SOUTH EAST WEST Sector Scanned Satellites(200E) High Ground (900E) Map of Test Location showing Key Features of Radio Map Antenna Site

The measurements were repeated with the system sensitivity at maximum Similar features More detail in the sky Can see water vapour concentration in clouds over high ground

More sky temperature detail can be seen

Map with no colour blending – shows maximum effect

A second series of measurements was undertaken Aim was to map the SUN Equipment moved onto the ‘Green’ for southerly view Unfortunately the SUN was below the building line It was obscured and no SUN image was obtained Experiment to be repeated in summer time

Building obscured views in most directions Some gaps between buildings Location of Antenna Hemisphere scanned North Location of Antenna satellites

A composite picture of the buildings was created This was used to make building outlines These outlines were applied to the radio image Able to identify some building features

Radio image of sky and buildings Shows satellites and unidentified signals Can see some details of buildings 45 0 Satellites SUN was behind building here Unknown signal sources Can see radio emission from chimneys Elevation 0 to 450 0 0 0 0 Azimuth 20 0 East of South South West North West

The project has shown that it is possible for students to construct a small 11GHz radio telescope Use to map the sky and show the ‘ arc’ of geostationary satellites Discover that the ground, buildings etc emit microwave radiation Record and analyse large data sets Make false colour images with software Understand some of the techniques used in Radio Astronomy