WD9EWK and balloons



Updated 10 August 2009

Amateur radio can be combined with lots of other activities.  There are many groups that make use of the radio with balloon launches.  Some groups are interested in the weather at higher altitudes, others try to see how high or how far balloons can travel, and some enjoy combining the radio hobby with the balloons.  There is a local group that does the latter, and I enjoy watching - and, sometimes, participating - in their activities. 

In the Phoenix area, Arizona Near Space Research is a group that has been launching balloons for many years, and most of their flights carry amateur radio payloads that any amateur radio operator can monitor - and sometimes use.  Some of the balloon payloads have included a TV transmitter, data transmitters, even a repeater that allows amateur radio operators to use small handheld radios to talk with each other over several hundred miles/km.  Some of these flights go over 100000 feet (almost 20 miles, or 32km, high)! 

My primary interest is in that repeater.  It is very similar in concept to the repeaters carried on amateur radio satellites, except that the ground stations do not need to make adjustments to their transmit or receive frequencies to use the repeater.  The ANSR balloons are a great way to test a station before trying one of those satellites. 

ANSR cross-band repeater
The ANSR repeater, which flies on many ANSR balloon launches, is one payload that allows amateur radio operators in several states to talk with each other as the balloon is in flight.  The repeater also is a focal point for the recovery teams, providing an easy way for those teams to stay in contact with each other until the balloon is on the ground.  Many radios with 2m and 70cm FM can be used with this repeater, with the following frequencies:  Some radios will allow this frequency pair to be programmed into a memory channel, others will allow both frequencies to be entered into separate VFOs, and some require the operator to manually change bands - or use two radios - for this repeater.  Consult your radio's instruction manual for that information.  The repeater has a courtesy tone to allow for breaks between transmissions, and an automatic identifier in Morse code to comply with FCC regulations. 

On past ANSR balloon flights, stations separated by as much as 777 miles (1250km) have made contacts through the repeater.  In October 2005, two Mexican stations separated by 477 miles (767km) - Alex XE2BSS in northern Baja California, and Juan Francisco XE2MXZ in northwestern Chihuahua state - made a contact with each other during the ANSR-26 flight.  I have used a small VX-2R handheld radio outside my house to make contacts through the repeater, including contacts with both of those Mexican hams during that flight.  In July 2003, as I was driving from Phoenix to Flagstaff AZ, I used the ANSR repeater to talk with people. 

Here are some maps showing the approximate coverage of the ANSR repeater, when the balloons are launched from central Arizona (south of Phoenix). 

ANSR repeater coverage map at 50000 feet when launched from central Arizona
ANSR repeater coverage at 50000 feet (15.2km)

ANSR repeater coverage map at 75000 feet when launched from central Arizona
ANSR repeater coverage at 75000 feet (22.8km)

ANSR repeater coverage map at 100000 feet when launched from central Arizona
ANSR repeater coverage at 100000 feet (30.5km)

Maps courtesy of Ralph Wallio, W0RPK

Other ANSR payloads
ANSR balloon flights generally carry APRS transmitters, allowing the balloons to transmit data regarding their locations, where they are traveling (speed and direction), and - after the balloon bursts - even predictions on where the balloon will land.  These transmissions are normally on 445.950 MHz FM using 1200bps AX.25 packet, and relayed into the 144.390 MHz APRS network where the balloon's location can be seen on the Internet. 

On some flights, there is a PSK31 transmitter that sends much of the same information that the APRS transmitter does - except on the HF bands.  One flight in June 2004, the PSK31 transmitter operated on 3 HF bands (17m, 20m, 30m) as a test of HF propagation where the transmitter was on a balloon.  Being near the launch site, I could copy most of the transmissions easily, and others several hundred miles/km away could do the same thing. 

Other flights have carried a television transmitter, providing live video to go along with the data transmitted from the balloons.  I have not tried to receive this video, but it is a great idea. 

Links to more ANSR information
This page is not meant to be the definitive source of information for the ANSR balloons and flights.  If you would like to read more information about the group and its balloons, please follow these links: 
WD9EWK/VA7EWK - Ham Radio