U4B Flight Testing has begun


VE3KCL
 

A stripped down version of the U4B is now in the air currently flying at over 100 knots mid Atlantic.
In the coming months I should be launching various setups of the U4B balloon transmitter to check out any potential snags while utilizing more and more features of the Hans Summers STM32 creation.
Winds are good this time of year but the solar radiation is pretty poor up north.
This version is transmitting at minute 4 and minute 6 every 10 minutes on wspr on 10.140120 MHZ on channel 31 under call VE3OCL
More information here : http://qrp-labs.com/flights/u4b1.html

73 Dave VE3KCL


Graham, VE3GTC
 

Very cool Dave - go go gadget U4B VE3OCL!

I was just reading that a British Airways flight from New York to London set a subsonic cross Atlantic flight  time due to a very strong jet stream associated with a recent storm in Europe  - under five hours but I don't recall the exact time.

cheers, Graham ve3gtc


On Sun, Feb 9, 2020 at 8:34 PM VE3KCL <airdry@...> wrote:
A stripped down version of the U4B is now in the air currently flying at over 100 knots mid Atlantic.
In the coming months I should be launching various setups of the U4B balloon transmitter to check out any potential snags while utilizing more and more features of the Hans Summers STM32 creation.
Winds are good this time of year but the solar radiation is pretty poor up north.
This version is transmitting at minute 4 and minute 6 every 10 minutes on wspr on 10.140120 MHZ on channel 31 under call VE3OCL
More information here : http://qrp-labs.com/flights/u4b1.html

73 Dave VE3KCL


Tim Wiwel
 

Will be watching for VE3OCL.  Currently we are stuck in Morocco on our second pass. 

Tim KM4EFW

On Sun, Feb 9, 2020 at 8:34 PM VE3KCL <airdry@...> wrote:
A stripped down version of the U4B is now in the air currently flying at over 100 knots mid Atlantic.
In the coming months I should be launching various setups of the U4B balloon transmitter to check out any potential snags while utilizing more and more features of the Hans Summers STM32 creation.
Winds are good this time of year but the solar radiation is pretty poor up north.
This version is transmitting at minute 4 and minute 6 every 10 minutes on wspr on 10.140120 MHZ on channel 31 under call VE3OCL
More information here : http://qrp-labs.com/flights/u4b1.html

73 Dave VE3KCL


Glen Leinweber
 

Been watching SpaceWeather.com where they note that up north, the stratosphere
is unusually cold, creating some amazingly colourful crystal clouds. Apparently
they may appear when temperature is -80C.
I'm curious what steps Dave has taken to keep his "package" temperature so
warm (looks like about 0 C)?


Tim Wiwel
 

On ours, I glued the Tx to the back of the solar cell with no other insulation.  We are seeing temps as high as +12C with ambient of -45C.  Just about every day the first packet is seen at about -20C on board.  On board temps have ranged from -24C to +12C with ambient from -65C to -40C.    The on board temp tracks well with the battery voltage. 

On Mon, Feb 10, 2020 at 11:30 AM Glen Leinweber <leinwebe@...> wrote:

Been watching SpaceWeather.com where they note that up north, the stratosphere
is unusually cold, creating some amazingly colourful crystal clouds. Apparently
they may appear when temperature is -80C.
I'm curious what steps Dave has taken to keep his "package" temperature so
warm (looks like about 0 C)?


VE3KCL
 

Hi Glen,  As Tim said the back of the solar panels are pretty warm. This rig has a 1/16" piece of foam with the solar panels glued on the top and just under that is the radio in a foam box. Ambient temperatures are in the -45c range and the radio often reports temperatures above freezing. The U4B has the potential to switch telemetry and can send tele of other the sensors in alternate transmissions ... so on future flights we will report inside and outside temps and .. .perhaps gama radiation and cloud cover on the earth's reflectivity.... a simple indicator with a down facing solar cell to tell if you are flying over clouds. The current  data indicates U4B1 may have a broken solar panel limiting the current to mid day tx only.... The firmware Hans has made, will have potential to stop reporting its normal 10 minute tx so frequently and after a few months of flying ( or predetermined time ), check in once a day as not to clutter up the bands. Even using these cheap chinese balloons, there is the potential to stay aloft for 1/2 a year or more.. and that could be too much reporting for the bands. Next flight we will probably try a few more things out.  The U4B1 is headed north for a few days and without a battery on board this flight,  I expect it will be silent till Valentines day.

73 Dave VE3KCL