2013-09-14 Kickoff Meeting[W2CXM]

2013-09-14 Kickoff Meeting

Vet basic design. Anything missing / incorrect?
We need to spec out and acquire the Mosfet transistors that we'll use for the radio and nichrome wire.
We need to find a piezoelectric buzzer that will run on 3.7V, and use less than 40ma.
Do we need a resistor or something else to bring the LED into Spec?
We need to weigh all our provisional components. How much lift do we need.
Balloon options
- Mylar + Helium. Can we find a cheap source on campus?
- Mylar + Hydrogen. We could make some.
- Hot air. We'd need to craft the balloon from very light materials.

Circuit looks good!
- We'll drive the LED and buzzer from the Atmel directly
- Atmel Tiny 13 can drive approx 40mA per pin
- Top power draw of Atmel is 200mA
- Need to find a TO-92 package MOSFET/BJT that will work.
- Need a 0.1uF bypass cap for the Atmel
- The Alinco DJ-C4T radio is about 300mA on TX, 70cm band.
Parachute
- Total weight of system
- Desired landing speed (usually 15 ft./s)
Gas system
- Can we get a helium source?
- Are we going to make hydrogen from drano + Al foil for fun & profit?

Test nichrome trigger on battery with MOSFET/BJT
Test nichrome trigger's capability to burn the nylon string
Test the shock load of the nylon string.
Get a dummy weight and drop a parachute off of some building (this is totally not sketchy).
Test the radio under repeated power cycling (will it hold programming?)
Atmel Tiny programming/debugging
Test balloon lift properties with various gases.
Foxhunt the Alinco to test range/signal strength, etc.

Jon
- ~~Get appropriate transistors!~~
- ~~Get a buzzer that's obnoxious and runs on < 40mA @ 3.7V~~
- ~~Get a 0.1uF cap~~
Matt
- Parachute calculations in spreadsheet for reference
- Parachute diameter, landing velocity, mass of system
Mike
- Total weight of system
  - Alinco
  - Atmel circuit stuff
  - Battery
  - Nichrome, etc
  - Container (bottle)
- Work on containment/bubblewrap system.
- Program the Atmel to do cool things
  - Twiddle a pin to make more sounds
  - Turn on/off the radio
  - Time the nichrome trigger
Stephen
- Look at gas/balloon sources
- Optimize gas sources on pricing/availabilty/# of launches.
- Check out airgas, a local? supplier.
Jules
- ~~Get nichrome wire~~