1. COMS Transceiver – RF DataTech LRT470 Frequency: 432-442MHz Operation: Half-Duplex Max. RF Transmit Power: 750mW Typical Power Draw at 750mW RF: 3.5W Bandwidth: ≤ 25kHz Modem – PIC 16C711 from RF DataTech Modulation: 4800bps GMSK Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY Architecture

2. Link Budget Down-Link Ebno required = 9.6 dB for a bit error rate of 10 -5 [Jan_King_Calculator.xls; http://cubesat.wikidot.com/local--files/amsat-colloquium- 2007/Jan_King_Calculator.xls ] Modem chip from RF DataTech is a Microchip PIC. A board will be built to interface it to the transceiver and MCU. A circuit diagram has been supplied by RF DataTech. Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY Up-Link

3. Concept Variable voltage dual output power supply – zero to 800V Preamp Shaping amp DiscriminatorBuffer HV Power supply Power controller V/I Status monitor To MCU From MCU MCP Incident dust particles cause plasma-induced electron cascade in single microchannel plate (MCP) with single terminal anode. Charge pulse from anode goes through electronics chain, which produces a pulse-height signal to be read by the MCU PAYLOAD Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY

5. 1 st July 8 th July 17 th July 14 th July 21 st 22 nd July 24t h July 25 th 1 st August 6 th August Lab work Gain calculations Electronics testing MCA setup Detector assembly Vacuum pumpdown HV supply setup Electronics redesign First Power-up Detector repair and reassembly Second power-up? Test plate voltage 700V Gap voltage 100V Maximum safe plate voltage 850V Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY

6. Flight design Detector body height = 4.3mm Mass (assuming density is similar to aluminium) = 14g Approximate specifications: Power consumption: Plate supply = 70mW Support electronics = 50mW Detector area (assuming 46mm diameter disk) = 16.6cm 2 Open area = 10.5cm 2 Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY

7. Budget Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY SubsystemTotal CostCost to Date MECH/OBDH£2992£3819.79 ADCS£70 PSU£12000£1761.28 COMS CAM PAY £850 £184 £3,400 Launch Testing and development £20,000 £5,000 (excluding Heidelberg) Contingency (30%)£13,242 TOTAL COST£57,738£5351.07 Remaining Costto Completion £32157 to Orbit £52157

8. Mass Budget Internal Configuration Slot No.Spacing (mm)SubsystemMass (kg)Connector Masses (kg) Area (mm squared) Bottom - 04.5OBDH0.074? 8645.95 0 -125.0COMS0.1150.016 4056 1 – 215.0PSU + BATTERY0.152960.00098 9216 2 – 315.0ADCS + MODEM + PAY0.10.00098 4704 so far 3 – 415.0PAYundefined0.00098 undefined 4 - Top12.9DETECTOR + ANTENNA0.070.00117 undefined StructureMech0.170.01856 ExternalSolar Panels0.033750.009 Total87.40.715710.04767 Reserve0.00.23662 Summer Review 6 th Aug. 2008 SRC SPACE ACADEMY

9. Next Steps Summer Review 6 th Aug. 2008 SRC PSU Fix BCR1 Go through battery charge / discharge cycles Select and purchase Solar Cells Test PSU with the solar cells OBDH Flight board needs to be tested MCU needs to be programmed Subsystems need to be physically interfaced Subsystems need to be run from MCU ADCS Power consumption test whilst connected to the Flight Control Board Axes sensitivity deviation test Refining of electrical components on ADCS board PAY Laboratory Calibrations Heidelberg accelerator testing Support Electronics construction Detector body prototyping and construction SPACE ACADEMY