[OZAPRS] VK2HAB 25/05/16

[Matthew Cook]

Hi Norm,

That sounds about right with respect to range, height is might !

Also don't forget that if you've got local traffic on a digi that this will
tromp on a balloon payload even at altitude.  It all comes down to sneaking
through the gaps.  Even with altitude you still have free space path loss
and the capture effect to contend with a the digi receiver.   It is always
sensible to run open squelch with software DCD if your packet engine
supports it.  That means weak signals don't have to crack the mute of the
radio first or get truncated if it drops too low.

Another quirk with balloons is the antenna pattern at altitiude can have
severe nulls in it, so being directly under a balloon can make it very
difficult to decode (from bitter experience) when people 50km or more can
copy it fine.  YMMV.

73

Matthew
VK5ZM




On 25 May 2016 at 17:44, Norm McMillan <vk3xci at gmail.com> wrote:

> Thank you Mathew,
>
> 100,000 feet  is 30480meters, range 625km.
>  VK3RBT to VK2HAB 510 km.
>
> Seems odd that VK3RBT picked it up but not VK3RBX, which is closer. Better
> check the squelch/sensitivity on RBX I guess
>
> norm
> vk3xci
>
> On Wed, May 25, 2016 at 4:55 PM, Matthew Cook <vk5zm at bistre.net> wrote:
>
>> Norm,
>>
>> Yes 100,000ft for a HAB is not uncommon.  See if you can find an online
>> radio horizon calculator and punch in 100,000ft. Take the position of the
>> balloon when you received the posit and draw a circle around it from the
>> horizon calculator.  I'm fairly certain you'll find Bambil tanks is within
>> this circle.
>>
>> We regularly have VK3 stations receive our HAB telemetry with the balloon
>> 25kms or more in to the stratosphere.  Height is might !
>>
>> 73
>>
>> Matthew
>> VK5ZM
>> AREG/Project Horus
>>
>> On 25 May 2016 at 16:12, Norm McMillan <vk3xci at gmail.com> wrote:
>>
>>> Copied a few (20 or so) packets from this event. the path is interesting
>>> to say the least. Is there a digi not correctly identifying or did VK3RBT
>>> at Bambil Tank REALLY receive the balloon direct.
>>>
>>>
>>> 0:TNC->
>>> VK2HAB-11>APT314,VK3RBT-1,VK2RBX-1,WIDE2*:!3349.O1S/14701.26E0161/003/A=100594/UpLift
>>> Balloon Flights|$"!!!!|
>>>
>>> And did it really make it to 100594 feet?
>>> And what does the   |$"!!!!|   at the end mean. I noticed the first two
>>> characters change as the flight progressed
>>>
>>> Due to my inexperience with xastir I didn't log it, but I have a screen
>>> shot!
>>>
>>>
>>> norm
>>> vk3xci
>>>
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