Field Day 2026
Balloon Flight 20 miles High with Ham Radios
Mark
Hoeft, WA5TBK
Mark will talk about the San Francisco High Altitude Balloon Club https://sf-hab.org He will
tell us about the flights, which rise to over 20 miles high! The payloads
include a dual-band repeater, APRS on LoRa, Meshtastic and a MeshCore repeater.
Topics
· Who Is Mark Hoeft, WA5TBK
· High Altitude Ballooning (HAB)
· San Francisco High Altitude Balloon Club SF-HAB
· SFHAB-11 MeshCore Repeater Payload (WA5TBK)
· National Weather Service Balloons
· Pico Balloons
· Additional Information
Who Is Mark Hoeft, WA5TBK
|
|
· Software Engineer and Manager at HP for 22 Years · Got Ham License KE6TYS in 1992 · Rejoined as KO6JUV in 2025 · Took over Father’s Call sign WA5TBK · “Mark in Lompico” “The Balloon Guy” · ARES |
High Altitude Ballooning (HAB)
· https://www.bing.com/images/search?q=Amateur+Radio+high+alttude+balloons
· https://www.youtube.com/results?search_query=launching+weather+balloon
· Amateur Weather balloons
· MAX <12lbs, 6lb each payload; May 9 flight was 4 payloads 4.57lb, 2075gm
· 105,000’, 20 Miles, 32,000m High
· Air Presure: 1% .15 PSI 1/100 Sea Level
· Expand to 35’ and bursts. 145 mph
· -70 degrees C
San Francisco High Altitude Balloon Club SF-HAB
· Launches and Chases every couple of months
· Mostly Hams
· Up to 6 radios on a Balloon
· Hit the dual band repeater and MeshCore 20 Miles up
· Mark WA5TBK will post on https://k6bj.groups.io
· https://amateur.sondehub.org
· Viewing on Google Earth from Walnut Creek
· https://groups.io/g/sf-hab-chatter/message/1166?
· https://groups.io/g/sf-hab-chatter/message/1307?
· Next Flight: Tomorrow June 28th
· All are welcome Launch and Chase (need co-pilots)
· Launch from East Bay typically
|
441 MHz
input 147.58
MHz output pl 162.2
Hz |
500 mW |
Crossband
Repeater |
|
431.05 |
25 mW |
UHF
Radiosonde - Horus Binary |
|
912.125 MHz ISM |
158 mW |
Meshtastic Geiger and Router |
|
906.875 MHz ISM |
158 mW |
RAK Meshtastic |
|
910.525 |
158 mW |
MeshCore – WA5TBK |
|
|
50 mW |
Wenet |
|
433.775
MHz ISM |
150 mW |
LoRa APRS |
|
|
|
Multiple
GoPros |
|
Radar Reflector
and Parachute |
SFHAB-11 MeshCore Repeater Payload (WA5TBK)
· Call Sign “SF-HAB.org 11”
· Any Channel repeats but only those directly heard by the balloon
· All forwarded as 0-hop to prevent Storm
· You can request Telemetry with GPS
· Truck Companion node logs all packets -> USB -> PC for Post Flight analysis
· Send MeshCore messages to your friends across that state
· 17.1 Degrees incline from Santa Cruz
· Can see most of California and other states from 20 miles up
· Radio Horizon 440 miles
· +22 dBm, 158 mW
· Meshtastic reached San Luis Obispo
· Monitor #Public for in-flight messages
National Weather Service Balloons
· https://www.bing.com/images/search?q=nws+weather+balloons
o This Payload: 6/12/2026 5:50pm https://sondehub.org/X4656707
o This Morning, 6/25/2026 6:05am https://sondehub.org/X4666320
· https://predict.sondehub.org/ sfhab11
· To follow one:
o Click on black circle near Alameda
o Select “12 hours”
o Left side will open, click on plots
o Copy “Serial Number”
o Enter into https://sondesearch.lectrobox.com/analyzers/kml-converter/
o Click download to see 4D Rollercoaster map in Google Earth
o 404Mhz (RTL-SDR?)
Pico Balloons
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|
· Super-pressure balloons 3’ at launch and at 40,000’ · https://www.bing.com/images/search?q=pico+balloons · 20m WSPR · 1.8gm U4B radio with GPS · 8-17 times around the world, up for months or longer · https://qrp-labs.com/circumnavigators.html#b64 · https://qrp-labs.com/flights.html |
Additional Information
· Linux in the Cloud
o https://www.digitalocean.com/
o $4 a month
· Domains
o ham0.cc (my tinyurl redirector) cost $34 for 10 years