Day 58 update: 11-Jun-2020
Day 52 update: 05-Jun-2020
Day 48 update: 01-Jun-2020
Day 46 update: 30-May-2020
Day 44 update: 28-May-2020 (two days)
Day 42 update: 27-May-2020
Day 41 update: 26-May-2020
Day 39 update: 24-May-2020
Day 36 update: 21-May-2020
Day 35 update: 20-May-2020
Day 34 update: 19-May-2020
Day 33 update: 18-May-2020
Day 32 update: 17-May-2020
Day 31 update: 16-May-2020
Day 30 update: 15-May-2020
Earlier updates in lap 2
Earlier updates in lap 1
This is the 6'th test flight of the new U4B tracker. For details see below.
U4B-6 was launched from Toronto by Dave VE3KCL on 18-Apr-2020.
U4B-6 uses callsign VA3UAL and the old-style telemetry channel 03. The WSPR report is at minutes :06 :16 :26 minutes past the hour, followed at :08 :18 etc by the QRP Labs telemetry packet.
U4B-6 lost its fight against icing today, last report was at an altitude of 240m on 11-Jun-2020 at 0216Z. The left chart shows a zoomed graph of the altitude over the last few days. RIP!
A complete Excel file of data and telemetry for U4B6 can be downloaded by clicking here.
Nice copy of the balloon glyph of U4B-6 and in one of the images, U4B-4 on the same screenshot, by TA4/G0UPL in SW Turkey KM46
U4B-6 completed its second circumnavigation!
<Several "balloon sightings" today too from the QRSS enthusiasts:
Andy G0FTD in UK, the U4B-8 balloon glyph clearly visible at the right, and U4B-6 more weakly towards the middle.
Bob K4RCG has U4B-8 top left, and a very strong signal from U4B-6 burning up his radio, at top right
Vernon VE1VDM again has a nice picture, showing both U4B-6 and U4B-8 clearly visible
Bill W4HBK has very strong signals from U4B-8, and U4B-6 pretty good too!
Reports were received of the balloon glyph; below shows Vernon VE1VDM's hat-trick, he copied U4B-4, U4B-6 and U4B-8 glyphs all at the same time! The image from W4HBK shows U4B-6 and U4B-8.
The screengrab below is by Dave Hassall WA4DJJ and shows the U4B-6 balloon glyph flying by on his screen. Dave runs a very impressive array of 13 QCX 5W CW transceiver kits converted for grabber operations, and the photo below; see his website http://www.qsl.net/wa5djj/
More icing problems yesterday (09-May-2020) hit the altitude again, but again, U4B-6 thawed out and recovered to reasonable altitude. One image below shows a zoom on the altitude graph of the last few days.
U4B-6 had some nervous moments today as probable icing took the altitude down to 8,720m before a gradual recovery!
Both U4B-6 and U4B-7 were awake today. U4B-6 was a frequent visitor to my WSPR log and to my Argo screen with the distinctive balloon glyph appearing many times through the day. Occasionally U4B-7 showed up to and on a couple of occasions they were there next to each other on the screen, very cool.
Today U4B-6 completed its first circumnavigation!
Note: On 30-Apr-2020 WSPRnet suffered an extended outage so part of the day's data is not available.
Today Bill W4HBK copied the balloon glyph on his own receiver in Florida (above right); alongside the glyph of U4B-7 (above left), which additionally has a little slow-Hellshreiber "7" to the lower left of the balloon image. Beautiful picture!
Nice images of the balloon glyph from KL7L in Alasaka, and W4HBK operating a remote grabber in Hawaii.
Glyph copied by SA6BSS
Bill W4HBK reports: "The glyph from Dave's little bird came thru to the W1NT KiwiSDR this morning as it was cruising over Greece. NT uses a 500 foot Beverage aimed to EU....oh the luxury of such receiving wires!"
Balloon glyph reception examples by WD4ELG and VE1VDM
A trouble-free ascent to floating altitude. Balloon glyph reception by W4HBK.
Note the presence of large dogs on the Toronto beach, who took a particular interest in trying to eat the U4B. However after a few anxious moments, physics got the better of them and it escaped safely into the air...
This is the 6th test flight of the new U4B tracker. U4B-6 was assembled by Dave VE3KCL. This YouTube video explains the features of the U4B tracker.
The BASIC program listing:
5 LET C = 35 10 PRINT BT 11 IF BT < 3200 12 SLEEP 10 1 13 GOTO 10 14 ENDIF 15 LET FR = 26999982 20 OUT 9 0 25 GPS 300 "$PSIMNAV,W,3*3A" 26 OUT 9 CL 30 PRINT BT 32 IF BT > 3800 33 LET I = 1 35 GOTO 40 38 ENDIF 39 LET I = 0 40 SLEEP 10 5 41 CW 0 14097220 12 0 " VA3UAL" 42 CW 0 14096960 5 0 "*01IFLCNAP8Q7R6R5S0S0S5R6R7Q8PANCLFI*" 43 CW 2 14097220 3 6 "*120*" 65 TELE 70 GOTO 15 -6 testing low dual power thresthold frequency 14097020 VA3UAL modify sleep voltage is measured right after gps lock
Prior flights in the series used a slow FSKCW "TT" transmission to warm up the system, ready for WSPR transmission (which must be drift-free). But in U4B-6 we decided to have fun with a little Balloon glyph which is created by the custom shift specification in the command at line 42. As in the Ultimate3S kit, the first two numbers after the asterix specify the duration of these symbol; in this case, "01" therefore means a symbol duration of 1 second; the subsequent characters represent a shift relative to the base frequency of 14,096,960, that trace out the pattern of the balloon.
In the photos below you can see how the balloon looks on the WSJT-X waterfall (which is rotated 90-degrees); some examples of the balloon glyph reception using the more common horizontal scrolling display for weak signal (QRSS, FSKCW etc) enthusiasts are shown in the Day 1 and Day 2 updates above (for example).