High Altitude Balloon - VK3YT on WSPR (and JT9) - STILL UP!

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ZL1RS
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High Altitude Balloon - VK3YT on WSPR (and JT9) - STILL UP!

Another high altitude balloon experiment by VK3YT carrying a solar powered 25mW GPS locked WSPR + JT9 transmitter is scheduled for launch at 21:00 UTC on Friday 26 Dec 2014 (8am Saturday morning local time in VK3). This launch is called "PS-30" and its expected track is generally eastwards from VK3. WSPR signals from the balloon borne HF data transmitters of previous launches have been decoded worldwide when ever / where ever the propagation paths are favourable. More ...

The balloon position will display on the WSPRnet.org mapping according to WSPR decodes received as the encoded grid locator is updated by the GPS along the flight route. It will also appear on the mapping at the 'Space Near Us' web site (aka SNUS) according to the JT9 decodes received ... http://spacenear.us/tracker/?filter=PS-30 (this link will re-direct to a new tracking display format on http://tracker.habhub.org/ ) This site will also carry the decoded telemetry showing various data including altitude, the speed that the balloon is traveling at, battery voltage, etc.

Frequencies:
WSPR on 30m (dial 10.138700Mhz) and 20m (dial 14.095600Mhz), both are the standard WSPR frequencies for those bands.
JT9 on 30m (dial 10.141000Mhz for a JT9 signal at 1000Hz) and on 20m (dial 14.074000Mhz for a JT9 signal at 1000Hz).

Time and frequency schedule:
(minute : band : mode : condition)

00 30m // Mandatory JT9 and WSPR, two per hour
06 30m // Optional JT9 - batt full
10 20m // Optional JT9 and WSPR - batt low
16 20m // Optional JT9 - batt full
20 30m // Optional JT9 and WSPR - batt low
26 30m // Optional JT9 - batt full
30 20m // Mandatory JT9 and WSPR, two per hour
36 20m // Optional JT9 - batt full
40 30m // Optional JT9 and WSPR - batt low
46 30m // Optional JT9 - batt full
50 20m // Optional JT9 and WSPR - batt low
56 20m // Optional JT9 - batt full

"batt full" means a transmission will occur in this time slot only when the battery is fully charged (>4.2V)
"batt low" means NO transmission will occur in this time slot if the battery voltage is low (<3.4V)

Example:

10 20m // Optional JT9 and WSPR - batt low

means that at minute 10 and minute 11 past the hour, two blocks of telemetry will be sent using JT9 on the 20m JT9 frequency, followed by a WSPR transmission sent at minutes 12/13 on the 20m WSPR frequency, as long as the battery voltage is above 3.4V

Previous balloon flights have lasted from a matter of hours (suspected defective balloon), up to several days with distances physically traveled by the balloon extending as far as to South America. Recent flights have carried the present HF data transmitter configuration rather than the VHF APRS style transmitter used in earlier flights and normally used by other high altitude balloon experimenters. The HF data transmitter has of course allowed tracking of the balloon from thousands of km away rather than the few hundred km provided by VHF line-of-sight signals from the balloon's typical flight altitude of around 8000 to 8400m ASL.

[edit 05 Jan 2015 at 0755 UTC - add a missing 'optional' transmission sequence to the timetable at minute 56]