Flight Wisp1c_10
Planned changes
- Two 36" Qualatex envelopes. Unstretched. Using Hydrogen this time.
- Transmit frequencies: 20 meter band only. 10 minute intervals.
- New code version (wisp1k). Additional telemetry is now stored in EEprom. A secondary telemetry packet will be sent hourly. The data in the secondary packet includes total number of transmit cycles, number of tracker boot-ups, number of watchdog resets, and number of GPS resets.
- Gatewayed to APRS at kd2eat-10. The secondary telemetry packet data will not be sent to APRS, but can be manually decoded for diagnostic purposes.
- Antenna built the same as Wisp1c_9, but additional tether added between the end of the counterpoise and balloon, to reduce potential interference.
- VCC on the board is reconfigured to 3.3 volts (from 2.5 and 2.7 on previous flights) to maximize transmit power.
Preparation
As per the previous flights. Nothing particularly warranting new photos.
| Item | Weight (g) |
|---|---|
| Tracker |
13.4
|
Tape and String attaching balloons
|
2.3
|
| Free Lift |
7.4
|
| Total |
21.7
|
Preflight prediction
Looks pretty good:
Day 1 - 9/15/2016
It was a glorious day to launch from my building!
Here are pictures of a pair of balloons in the same configuration as I launched today. I just didn't happen take a picture of today's balloons. Today's were filled with hydrogen, and looked a little less full than these.
Here's the tracker, getting it's first lock and doing a transmit test prior to launch. Note the blue LED illuminated on the left side. That's the transmit light.
And it's off!!!! The winds were calm. It went basically straight up! You can see the tracker dangling below, and if you look carefully, the antenna hanging below the tracker.
It flew 370 miles, starting in grid square FN12sk and ending in FN51hl. More statistics are in the table at the bottom of the blog.
The altitude with the hydrogen was quite nice. It floated comfortably around 10,333 meters, peaking at 10,666 a few times.
The GPS still had a few late locks, but none missed and no resets to speak of. There IS a problem with the new telemetry packet. They were sent on schedule, but there seems to be a problem which is causing the telemetry callsign to be garbled at times. I'll have to investigate it more.
The antenna performed VERY well. Below is a map of the stations that received it today.
Predictions for the future still look pretty consistent. It's going to loop around Europe, if it makes it there. The weather ahead looks clear, so barring any problems, I'm optimistic that it'll be there in the morning.
The tracker awoke on schedule in grid GNOO0b, having traveled 562 miles overnight. We ended the day in grid GN61ek having traveled 592 miles by light of day. Very nice!
The altitude held steady at about 10,777 meters throughout the day.
APRS coverage was great throughout the day. Here's a map of the stations that received the tracker today.
Here are pictures of a pair of balloons in the same configuration as I launched today. I just didn't happen take a picture of today's balloons. Today's were filled with hydrogen, and looked a little less full than these.
Here's the tracker, getting it's first lock and doing a transmit test prior to launch. Note the blue LED illuminated on the left side. That's the transmit light.
And it's off!!!! The winds were calm. It went basically straight up! You can see the tracker dangling below, and if you look carefully, the antenna hanging below the tracker.
The altitude with the hydrogen was quite nice. It floated comfortably around 10,333 meters, peaking at 10,666 a few times.
The GPS still had a few late locks, but none missed and no resets to speak of. There IS a problem with the new telemetry packet. They were sent on schedule, but there seems to be a problem which is causing the telemetry callsign to be garbled at times. I'll have to investigate it more.
The antenna performed VERY well. Below is a map of the stations that received it today.
Predictions for the future still look pretty consistent. It's going to loop around Europe, if it makes it there. The weather ahead looks clear, so barring any problems, I'm optimistic that it'll be there in the morning.
Day 2 - 9/16/2016
The tracker awoke on schedule in grid GNOO0b, having traveled 562 miles overnight. We ended the day in grid GN61ek having traveled 592 miles by light of day. Very nice!The altitude held steady at about 10,777 meters throughout the day.
APRS coverage was great throughout the day. Here's a map of the stations that received the tracker today.
The prediction for the coming days has improved. It looks like we may not loop-de-loop after all. It's hard to be sure, but at least this hysplit model shows it curving out to the southeast, instead of back northwest!GPS reset
We did have one GPS reset today, and the new telemetry packet confirmed it. The transmit sequences should be 10 minutes apart. When we're late, it'll be some multiple of 2 minutes later. The GPS is reset if we can't get a lock for 5 consecutive minutes. Well, one of the transmissions was six minutes late. That indicated that the GPS should have been reset. Sure 'nuff, when the next secondary telemetry packet came out, on the hour, it showed that a GPS reset had occurred. Hurray for the new functionality. There's still a glitch causing some garbled data, but I'll track that down before the next flight.
Day 3 - 9/17/2016
The tracker woke up on schedule at around 4:14am Eastern in grid square HO61li, having traveled 1190 miles overnight. It was really moving fast today, averaging over 100mph for the day. We ended in grid square IP26qb after traveling 1105 miles in daylight. It was a little lower all day, around starting at around 10,444 meters, and gradually sinking to 10,222 meters near the end of the day. I'm hoping this is due to the high latitude, and not a leak.
The tracker was received very well throughout the day. Here's a map of the receiving stations during the 12 hour period of activity.
The hysplit predictions are improving. Many of them now show the payload traveling east, rather than doing a loop-de-loop. Yay!Day 4 - 9/18/2016
Day 4 went OK. The tracker awoke on schedule around 2:16am Eastern in grid square KQ18oq, having traveled 1136 miles overnight. It had slowed down significantly, moving at about 59 mph through the short day. It only beaconed for about 5 1/2 hours before it the sun was too low on the horizon. It's WAY up north, and the solar cells don't work so well. It ended the day in grid square LQ39xc, some 328 miles traveled by day. The good news was that the altitude was up again. Most altitude reports were at 10,666 meters.
The ensemble predictions for the trip are looking better. It's most likely to continue east, now, rather than looping around Scandinavia.Given the short day, I'm guessing it'll be about 2AM UTC (10pm EST) before we see the tracker again.
Propagation was poor today. The receiving stations are shown at the left. We averaged 3.3 receiving stations per beacon, and had the worst packet reception percentage to date, at 85%.Day 5 - 9/19/2016
Day 6 - 9/20/2016
It's "hide and seek" day for the tracker. No packets received during its short transmission window. Remaining optimisitc that it's just due to the short daylight cycle and extreme distance from receiving stations.Final Status
The tracker was not heard from after day 5. It's unclear what caused the failure.Statistics
| Day | Rcvd Pkts | Lost Pkts | Percent Rcvd | Late GPS locks | GPS Resets | Watch dog Resets | Farthest Rcv Station (miles) | Average stations / beacon | Max stations / beacon | Daylight Dist covered (miles) | Avg MPH |
|---|---|---|---|---|---|---|---|---|---|---|---|
1
|
118
|
4
|
96.7
|
4
|
0
|
0
|
3,738
|
7.5
|
15
|
370
|
37
|
2
|
110
|
10
|
91.7
|
5
|
1
|
0
|
7,986
|
7.4
|
18
|
592
|
57
|
3
|
120
|
8
|
93.8
|
2
|
0
|
0
|
9,483
|
15.2
|
25
|
1105
|
112
|
4
|
64
|
11
|
85.3
|
1
|
0
|
0
|
2,781
|
3.3
|
12
|
328
|
59
|
5
|
58
|
12
|
82.9
|
1
|
0
|
0
|
3,554
|
1.5
|
5
|
108
|
18
|
6
|
0
| ||||||||||
7
| |||||||||||
8
| |||||||||||
9
|
Hi there, I stumbled across your current flight from the HabHub tracker. This and some of your previous efforts are sensational! Do you mind if I ask a few (hopefully simple questions); The transmitter looks custom, is that correct? Are your balloons "zero pressure" (i.e., designed to vent)? At around 10Kms surely you're exposing the poor little thing to something like -50 or -60 deg. C temps... how does the transmitter hold up under that extreme without any insulation or heater?
ReplyDeleteYes, it's a custom tracker I designed and built myself. The balloons are launched only partially inflated. They reach superpressure at around 10,000m and stop swelling. Since there is very little extra lift at launch, the balloons swell but don't burst, and they reach equilibrium. They do not vent.
DeleteThe parts on the tracker board are carefully selected to assure that they are rated down to as low as -40c. I've seen them operate as low as -50 or -60, but the GPS can get squirrely (a technical term) at those temperatures. If you look at it in APRS (rather than HabHub) you can click on the "Telemetry" link and see the temperature data. It hasn't gone below -25c during the day. Not sure at night, since it's powered down.
Enjoy!
Hi Michael, really impressive work. I'm just moving into the hobby myself after completing a photography high-altitude balloon.
ReplyDeleteI'm wondering where you got your wind prediction results from. I tried going to the HYSPLIT NOAA site but their generated images are clearly very different from seemingly the interactive google map you have images of.
I took a good crack at searching for what the site must be but can't find anything like it really.
Could you pass along the URL?
Thanks!
doug
Doug, Sorry for the delay. Most of the images I got from the tracking were from: https://tracker.habhub.org/
DeleteFor initial predictions I also use http://predict.habhub.org.
Mike
Thank you Michael, very helpful!
ReplyDeleteI subsequently found the HYSPLIT site:
https://ready.arl.noaa.gov/HYSPLIT_traj.php
And a youtube which quickly walks you through how to use it:
https://www.youtube.com/watch?v=71OjOqySJwU
I've linked to both for people that may find this comment later.
I would ask another question if I can, about WSPR gateway to APRS.
I am implementing a WSPR transmitter and wonder what you specifically meant in your blog when you said your WSPR transmissions were "gatewayed to APRS."
That was from this post: http://hojoham.blogspot.com/2016/07/flight-wisp1c5.html
Basically, I like the APRS.FI site for tracking my APRS transmissions, and expect to be able to transmit WSPR ultimately, but would like to have my WSPR transmissions recorded on APRS.FI as well.
It wasn't clear to me if you were doing the gatewaying yourself (with your own software and receiver?) or if there was another mechanism you were using.
Thanks!
And also thanks for all the great information on your blog. I have read through it extensively and found it very helpful in my research while preparing to implement WSPR!
doug (KD2KDD)