WSPR Launch Process
Launching WSPR trackers can be a pain due to the very long length of the antenna.
Given the 20m (~14MHz) frequency we transmit on, the total length of of the dipole is ~33 feet.
For weight-reduction purposes, we've moved to using magnet wire for the dipole, and this gets tangled extremely easily.
The launch process we've gravitated toward looks to avoid tangling of the dipole wire.
This involves transporting the tracker to the launch site safely, as well as actually launching it safely.
The broad overview is:
Strain relief on the points where the antenna is soldered to the tracker.
Suspend the tracker from the balloon by the upper antenna.
(as in, no separate thread/ribbon, use the actual antenna to attach to the balloon)
Wrap the antenna halves around cardboard tubes for transport.
Unwrap the two halves in opposite directions at the launch site and avoid tangling.
Only attach the balloon to the upper half at the launch site (avoids transport issues).
Here are some photos that highlight the long lengths of wire in use for the WSPR antenna.
Anatomy of a tracker in flight.
Looking up during launch, antenna length requires long ribbon to balloon from tracker.
We don't use a ribbon anymore, we just use the top part of the dipole. The view is the same though.
Here is some strain relief on the tracker itself.
Some extra tape on the antenna halves keeps the pressure off the solder points.
Each half of the antenna is wrapped around a cardboard tube and lightly taped in place.
This is purely for keeping the wires untangled while transporting to the launch site.
At the launch site, unpack tracker and two cardboard rolls.
Keep the balloon held down with some water bottles attached to a ribbon on the balloon.
Then:
Unroll the bottom antenna, lightly tape in place
Unroll the top antenna, hold down with tape dispenser
Move balloon (held by water bottles) near to the end of the top antenna
Then tape the top antenna to the balloon.
Best to coil a few loops of the top antenna, fan out, and then tape. This provides more surface area for the tape to grab onto.
Once ready:
Move tape dispenser away
Detach balloon from water bottles (you now control the balloon with your right hand)
Walk toward the tracker and pick it up with your left hand (don't step on top antenna)
Lightly pull on the bottom antenna to detach the bottom antenna from the ground where it was lightly taped
Walk backwards to keep antennas away from your feet and one another
Once wind ok to launch:
Release balloon from right hand
Continue holding tracker with left hand with light grip (or open palm)
The balloon will lift the tracker from your hand and continue to rise until bottom antenna off the ground
Done!
