CricketSat Assembly Manual

CricketSat Background Developed at Stanford University –Space Systems Development Laboratory Part of the NASA student satellite program –Teach fundamentals of space hardware development –Space Grant Fellowship Program Funded support Vermont Space Grant Consortium (VSGC) –UVM campus Student Satellite Programs CricketSat –Lowest cost - disposable –Live telemetry BalloonSat –Larger balloon –Expensive instruments –GPS tracking system CanSat –Dropped by parachute from plane or rocket –Many instruments –Live telemetry –Test bed for CubeSat CubeSat –Earth-orbit satellite

Getting Started Your Parts Kit Your kit contains parts for two CricketSat sensors They are all mixed together in the same bag The second unit will not have an RF transmitter or antenna The second unit may be used for your final project Prepare for Assembly Make a hard copy print out of the following page It will help you identify the proper components Place the components with the matching picture on the sheet T.A. sign off TA:

C1C3C2 C4C5C6 U2 R1 D1 DIP Socket Notch U1: 555 Timer IC Dimple Pin 1 Flat Side Up U3: RF Transmitter 5-Volt Regulator 10K Ohm Thermistor Printed Circuit Board (PCB) 47 micro-Farad Electrolytic Capacitors Longer Lead Light Emitting Diode (LED) 0.1 micro-Farad Capacitors + - Black BandD2 - Diode + - B1: 9-Volt Battery Pins: Antenna Wires Battery Snap Connector + - Red Lead is Positive R4: 100 Ohm R2: 3300 Ohm R3: 680 Ohm Brown-Black-Brown-Gold Orange-Orange-Red-Gold Blue-Gray-Brown-Gold Negative White Band

Printed Circuit Board Metal layers - conductors –Front and back sides –Epoxy board - insulator –Traces provide the wiring –Vias - connect the front and back metal layers Front side of board –Components on this side –White silkscreen layer Component outlines Reference designators –Green solder mask layer Insulates exposed metal Back side of board –Solder on this side

Assembly Techniques Inserting Devices –Bend leads if necessary to ease insertion into board –While pressing component to board, bend leads at an angle –This will hold components in place while soldering –Just 4 or 5 components at a time Soldering –Use enough heat –A shiny Hershey’s Kiss shape Snipping leads –Flying leads may damage eyes! –Hold lead while cutting or point downward Bend lead close to board 45 degree angle is best Snip just above solder joint

Resistors and Diode First D2 - Orange Diode (Black Band to the Left) R OhmsR OhmsR Ohms Clip leads after this step...

Small Capacitors and Battery Clip Install Battery Clip Feed 2 inches of wire down through strain relief holes, from top side of board Push bare wire ends completely up through solder pad holes from bottom side of board Pull excess wire tight. Should look like this… Solder connection on top side of the board Trim excess wire from connection No bare wire allowed! Route wire down through these holes Solder wire to these holes Bottom View Top View + RED - BLACK Install Capacitors C4, C5, C6 0.1 uF Clip leads...

DIP Socket Use the vise alligator clip to hold in place or press flat against table surface while soldering Make sure that socket is flat to the circuit board and that all the pins emerge from the backside of the board before soldering in place Align socket with white outline provided on board Place the notch up, towards C4.

Installing the Taller Parts Install these Parts... C1, C2, C3 -Polarized White band (-) to outside of board U2 - Orientation Flat side left, towards C3 Push only half-way into board D1 LED -Polarized Longer lead (+), next to socket Make sure capacitors are mounted close to board surface to minimize movement U2 - Voltage Regulator Push only half-way into board Clip leads...

Install the Antenna There are four antenna holes Wires are soldered to the center two holes, and pass through the outer two Insert a bare wire end from the bottom side of the board through one of the two center marked antenna holes Rest it on a table surface as shown left The weight of the board should insure that all of the bare wire extends through the top of the board In this position, solder the connection on the top of the board as shown Repeat for the other wire Feed the free ends of the wires through the strain relief holes Pull tight to set as shown Snip excess bare wire on top of board No bare wires through the strain relief holes

Transmitter and Timer IC Install the transmitter as shown to the left Metal can faces towards antenna Make sure the module is soldered close to the board to minimize movement Locate Pin 1 on the IC, marked with a “dot” This end of the IC goes next to C4 Straighten pins if necessary and press into socket If pins bend while inserting into socket, remove IC and straighten pins. Clip your leads... Transmitter Module 555 Timer IC

Finally, the Thermistor Stands up above other circuits Search parts bag for two pieces of black insulation Slide insulation up to the body of the thermistor in order to insulate the leads Insulation prevents “short circuits” to other exposed metal leads Solder at location R1 on the circuit board

Short Circuit Test We want to make sure that there are no short circuits on the board Performed before connecting the battery for the first time Set the meter to the OHMS setting Touch the meter leads to the battery connector as shown Meter should indicate an open circuit Reverse the test leads and measure again Should be an open circuit reading again Contact your T.A. before connecting the battery

Live Test Connect the 9-Volt battery Observe the LED, it should be flashing around 1-2 Hertz RF Test: Use a UHF radio receiver tuned near 434 MHz to hear pulses Optional: Measure the voltage on the V+ and 5V test points TA: Sign-off on Parts Sheet Congratulations!

Prototype Development Area Thermistor Test Points Dipole Antenna RF Transmitter Module Timing Capacitor 5-Volt Regulator IC 555 Timer IC Flashing LED 9-Volt Battery Leads Timing Resistor Primary Features

Output Jack Noise Decoupling Capacitor Series Isolation Resistor Current Limiting Resistor (LED) Noise Decoupling Capacitor Protection Diode (Reverse Battery Connection) Noise Decoupling Capacitors Secondary Features