Welcome to the
Carroll County High-Altitude Balloon Experiment
Technical Results Page

See below for information about our humble CarrollSat-1 flight. You are welcome to participate with us on our next flight!

CarrollSat-1 was an Outstanding Success!


Tuesday, October 27, 2009

WESTMINSTER -- by Pat Kilroy -- We were caught by surprise. After the "SimSat, High-Altitude Experiments, Microcontrollers and More" Technical Session at the Mason-Dixon Hamfest & Computer Show on Sunday, October 25, several of us launched a tiny sensor-transmitter tied to a small latex balloon. Rich Mitchell built this "PICetSat Lite" module. The balloon was not much larger than one foot in diameter. We were pleasantly surprised by the loudness of the signal, the longevity of the flight and the robustness of the flight hardware.

Don't miss Steve Beckman's personal account, below.

Fast Facts (Post-flight)

Mission designation: CarrollSat-1
Sponsors: K3PZN, WA3NAN, NASA GSFC and individuals.
Launch date: Sunday afternoon, October 25, 2009.
Launch time: Released at 17:10:00 UTC (exactly 1:10 P.M. EDT.)
Flight time duration: LOS at 110 minutes aloft, nearly two hours!*
Launch site: K3PZN Space Port, at the Mason-Dixon Hamfest, in Westminster, MD 21157.
Launch site coordinates: 39.55583, -77.00000, ground level at 700 feet AMSL.
Mission Control: CCARC Mission Control Center set up (milling about) at the Carroll County Agricultural Center.
Flight ID: Callsign K3PZN, transmitting to all.
UHF balloon downlink: 433.920 MHz FM +/- 0.080 MHz, drifting, likely T and V sensitive.
Recovery team callsigns: None. This was designed as an expendable payload.
Telemetry Copied: See below for spreadsheets developing by N3SB, N3III and N8PK.
Sponsor Club: Carroll County Amateur Radio Club, Inc., P.O. Box 2211, Westminster, MD 21158.
Sponsor Club Web Site: http://www.qis.net/~k3pzn/

The PICetSat Lite module before flight, as built by Rich.
Click image for larger view.

PAYLOADS and Balloon Train Info

A PICetSat Lite flight module made by Rich Mitchell, N3III ...

Capsule structure: two standard white 10-ounce coffee cups, EPS "styrofoam" material, each trimmed in half, placed top-to-top, sealed with clear packing tape.
Capsule dimensions: about H 3.0 x W 4.5 x D 3.0-inch O.D., somewhat cylinder-shaped, wall thickness 0.2-inch, tiny PICetSat Lite module inside.
Flight battery: two watch batteries or as Rich described, "super coin cell batteries bought in bulk from an unknown Hamfest vendor over two years ago."
Antenna and feedline: Non-inverted Vee protruding from PCB and cups.
RF Power Output: about 10 mW (0.010 Watts).
Total mass of payload: 23 grams (0.81 oz., 0.051 lbs) max.
Capsule weight/size ratio: about 0.06 ounces per square inch.
Microcontroller: Revolution Education's PICAXE-08M
Onboard sensors: temperature (T) via a thermistor and light intensity (L) via a photodiode -- Rich's "one pixel" camera!
Balloon type: A KCI 30 30-gram pibal, filled with two-year old party-grade helium.
Ascent rate: Something between 50 and 200 feet/minute, a guess.
Float phase: No float phase. Only ascent & descent phases, drifting with winds aloft.
Footprint: Based on altitude, about 150-mile radius of Baltimore, Md.
Recovery, descent: Upon burst, flutter/tumble recovery, low mass & large surface area design predicts failsafe soft landing.
Recovery, landing: RDF-capable but battery capacity expected to be exhausted.
Ongoing Discussions: On the MCHUG e-mail reflector and club reflectors.

This PICetSat Lite module was smaller than the original PICetSat module that flew on the SimSat-3 mission!

The balloon flight trajectory after launch. Click image for larger view.

Telemetry Format (What You Heard!)

Here is the PICetSat sequence in 5 WPM Morse Code. It:

o Sent the "HI HI" salute to grab one's attention, then
o Sent the letter "F" for Frame, then
o Sent a sequential frame counter number, incrementing by one, each frame
o Sent "T" for Temperature, then
o Sent numerical code for temp, decreasing code for decreasing temp
o Sent "L" for Light, and then
o Sent a numerical code for light intensity, decreasing code for decreasing light on sensor.
o Then a silent period followed, resting to conserve battery and yield channel, and then
o Took sensor measurements and started over, repeating this cycle throughout mission.

At the end of every tenth frame (every frame number ending in zero) it:
o Sent "DE" for "from" and then its ID, the CCARC club callsign, K3PZN.

Example Frame:
HI HI F 160 T 852 L 992 DE K3PZN

Spreadsheets of Copied Telemetry, In Process

Steve Beckman, N3SB, PICetSat1-TLM-2009-1027sb.xls updated.
Pat Kilroy, N8PK, CarrollSat1-N3SBcopyTLM-v2009-1027pk.xls updating.
Rich Mitchell, N3III, Flight1-TLM-2009-1027rm.xls.

An Unbiased Account

As Steve described the event that very evening, ...
-----Original Message-----
From: n3sb@qis.net 
Sent: Sunday, October 25, 2009 8:56 PM
To: k3pzn-list@mailman.qth.net
Subject: [K3PZN-List] Hamfest and PICetSAT Flight

Hi Folks;

Fortunately we had good weather for the Mason-Dixon 
Hamfest today.  I think the hamfest went well; thanks 
to everyone who came out to help!  

Our Technical Presentation today featured Pat N8PK 
and Rich N3III, who talked about Amateur Radio High-
Altitude Balloons.  Pat discussed all the planning 
activities his team of students have been working in 
preparation for the SimSat-4 launch, now scheduled 
for Saturday October 31.  Rich showed off several 
versions of the PICetSat modules he'd built, and 
handed out some parts kits to the attendees.  

The presentation culminated in a PICetSat balloon 
launch.  The payload was a PICAXE-based module that 
contained a temperature sensor (a thermistor) and 
a light sensor.  The downlink transmitter was a 
10 milliwatt garage door opener transmitter module, 
operating near 433.920 MHz.  

The PICetSat balloon flight was a huge success!  We 
were able to copy the telemetry using HTs and rubber 
duck antennas for over an hour!  Using Rich's Arrow 
antenna, we copied over two hours of telemetry from 
the launch site at the Ag Center.  The balloon took 
a Southern flight path away from the Ag Center, 
and based on signal strength measurements with the 
beam antenna, may have turned a bit to the [east].  

When the telemetry downlink signal faded below our 
ability to copy, the balloon appeared to still be 
in flight, and was probably still climbing, with a 
good battery.  

This was a great demonstration, and it's going to 
be really hard to top this demo at next years' 

I've included the received telemetry below.  You 
should be able to import this info into your 
spreadsheet and plot the data to see what the 
PICetSat was doing during its flight.  If anyone 
was able to copy additional data frames, please 
pass them along.  Rich [or Pat] may be able to 
give us some help with translating the temp 
telemetry data to real temperature values -- 
either deg C or F.  It might also be interesting 
to perform some Fourier analysis on the Light 
sensor data to determine if there was a 
predominant flight capsule rotation rate.  

73; Steve, N3SB

[See Steve's telemetry data in the spreadsheet 
files above. -Ed.]


Our Thanks To:

o Mr. Rich Mitchell, N3III, Carroll County Amateur Radio Club, K3PZN.
o Mr. Steve Beckman, N3SB, Carroll County Amateur Radio Club, K3PZN.
o Mr. Gary Chatters, WA9ZZZ, the Goddard Amateur Radio Club, WA3NAN.
o More coming. Many more to list.

For info on this web page contact:

Mr. Pat Kilroy
Flight Systems I&T Engineer/Manager
SimSat Principal Investigator
NASA Goddard Space Flight Center
E-mail: Patrick.L.Kilroy@nasa.gov

Related Links

o You can visit the national balloon announcement web page, click on "ARHAB Balloon Schedules".

o Perhaps you will see one of our future flights nudge itself into the ARHAB records page. Scroll down and view the several categories.

o See also Bob Bruninga's tutorial on Radio Direction Finding (RDF) techniques, that we will use, as shown to be such a success on a CricketSat flight and the SimSat-3 mission!

IF YOU FIND an Amateur Radio High-Altitude Balloon (ARHAB) like a CarrollSat, or
what might be one, then please wait before disturbing it so that photo-documentation
and post-flight processing may be completed by the operators. Please call the phone
number on the recovery tag (301-286-1984) immediately. Thank you!

This is Version 1.02.0
Last Modified: November 19, 2009