Go to advanced search

by daveake
Mon Jan 16, 2017 9:16 pm
Forum: High Altitude Balloon
Topic: Aerial issues:
Replies: 8
Views: 9942

Re: Aerial issues:

I disagree about placing the payload aerial horizontally. The payload itself rotates continuously during flight so a horizontal aerial will cause frequent drops in the received signal. Pretty much every balloon flight uses a vertical quarter-wave aerial with ground plane, with the radiating part of ...
by daveake
Mon Jan 16, 2017 3:19 pm
Forum: High Altitude Balloon
Topic: from SDR to fldigi?
Replies: 12
Views: 12420

Re: from SDR to fldigi?

Seems like that raspi-config was run at some point and the serial port then disabled. The instructions assume that the serial port is enabled, which is the case on a fresh installation, but you may have disabled it at some point.

Dave
by daveake
Tue Jan 10, 2017 12:42 pm
Forum: High Altitude Balloon
Topic: Radio Communications: Proper Guide for Newbies?
Replies: 7
Views: 10967

Re: Radio Communications: Proper Guide for Newbies?

Well, the PITS software and hardware are all open-source so you can refer to those. The circuitry needed is shown here - https://ukhas.org.uk/guides:linkingarduinotontx2, however don't try and use that software method on a Pi, as it relies on accurate timing; instead use the serial port and send dat...
by daveake
Thu Jan 05, 2017 10:24 pm
Forum: High Altitude Balloon
Topic: Pi Zero in a weather balloon
Replies: 3
Views: 9530

Re: Pi Zero in a weather balloon

The BME280 is nice - SPI and I2C, and does temperature and humidity as well as pressure. However, at high altitudes the air pressure is very, very low (approx 1% of ground air pressure when at 30km, and approx 0.3% at 40km), and few sensors will read accurately at those pressures. Plus the relations...
by daveake
Fri Dec 16, 2016 2:18 pm
Forum: High Altitude Balloon
Topic: from SDR to fldigi?
Replies: 12
Views: 12420

Re: from SDR to fldigi?

I see that a couple of people joined, and posted the same message, but haven't responded to the replies. Replies appear in the large window just above where you type in your own messages. You/they were asked to post screenshots (as I said would happen). The other thing you can do is check to see if ...
by daveake
Fri Dec 16, 2016 10:54 am
Forum: High Altitude Balloon
Topic: Avoiding 'splash' down!
Replies: 6
Views: 9756

Re: Avoiding 'splash' down!

In my experience, the moment that anyone with a H&S badge gets involved, it's only going one way. It's just not worth the hassle of producing risk assessments etc when the end result will be "no". So for school launches I use helium.
by daveake
Thu Dec 15, 2016 11:20 pm
Forum: High Altitude Balloon
Topic: from SDR to fldigi?
Replies: 12
Views: 12420

Re: from SDR to fldigi?

That should work, however it's probably simpler to use the web client - https://ukhas.org.uk/ukhas:irc_channel Whoever helps, you'll soon be asked to post screenshots of the SDR s/w and dl-fldigi, so you might as well get those ready - e.g. upload to imgur.com. You can then post the links in the cha...
by daveake
Wed Dec 14, 2016 6:45 pm
Forum: High Altitude Balloon
Topic: from SDR to fldigi?
Replies: 12
Views: 12420

Re: from SDR to fldigi?

You need to use the largest peak. Be aware that cheap SDRs have a false peak right in the centre of the received band, so ignore that one. When you zoom in to the correct peak (the largest PITS-generated one) it will either be a single peak (meaning PITS is not set up correctly) or 2 peaks separated...
by daveake
Wed Dec 14, 2016 3:07 pm
Forum: High Altitude Balloon
Topic: Avoiding 'splash' down!
Replies: 6
Views: 9756

Re: Avoiding 'splash' down!

Yeah H2 is cheaper, though personally I've switched to using composite cylinders rather than the steel ones (much much much easier to carry around) and that brings the price back closer to that of helium. And yes, H2 is renewable resource so no concerns about using up helium. It also goes a bit high...
by daveake
Sun Dec 11, 2016 11:46 pm
Forum: High Altitude Balloon
Topic: from SDR to fldigi?
Replies: 12
Views: 12420

Re: from SDR to fldigi?

First, zoom in to confirm that it is a single peak. If so then most likely you've disabled the serial port, which is where the data stream goes to feed the RTTY transmitter. No data stream means one peak not two peaks. See the manual or online instructions which explain how to correctly set up the s...
by daveake
Sun Dec 11, 2016 11:41 pm
Forum: High Altitude Balloon
Topic: Avoiding 'splash' down!
Replies: 6
Views: 9756

Re: Avoiding 'splash' down!

I can't get a flight time of anywhere near 4 hours using your figures, so something is wrong. Roughly, that would be a 3 hour ascent and 1 hour descent, and 3 hours at 7.3m/s is an altitude of 79km. You're not going to get anywhere near that with any latex balloon. To reduce the distance travelled y...
by daveake
Wed Oct 05, 2016 9:34 pm
Forum: General discussion
Topic: How to do serial communication on Raspberry pi 3 using putty
Replies: 5
Views: 5574

Re: How to do serial communication on Raspberry pi 3 using p

stty is the command to configure serial ports.
by daveake
Fri Sep 23, 2016 8:14 am
Forum: General discussion
Topic: Anyone tried 4xAlkaline AA batteries on PiZero?
Replies: 40
Views: 5131

Re: Anyone tried 4xAlkaline AA batteries on PiZero?

Be aware that Lithium AAs start at about 1.84V, not the ~1.5V of an alkaline cell, so if someone does pop 4 of those in to your device then their Zero and USB device are going to see over 7.3V. Primary Lithium cells do lose voltage pretty quickly under load, but over-voltage damage also happens quic...
by daveake
Thu Sep 22, 2016 1:57 pm
Forum: Camera board
Topic: STICKY: Pi Zero not seeing camera module? Please read.
Replies: 37
Views: 40591

Re: Pi Zero not seeing camera module? Please read.

Yeah, dunno what happened there. The camera has been enabled all the time in raspi-config, and after the edit /proc/cpuinfo showed the changed value, yet raspistill couldn't see the camera. Odd. Anyway working now, which saves me desoldering this zero (hard-wired to GPS/radio) and replacing it. Dave
by daveake
Thu Sep 22, 2016 12:58 pm
Forum: Camera board
Topic: STICKY: Pi Zero not seeing camera module? Please read.
Replies: 37
Views: 40591

Re: Pi Zero not seeing camera module? Please read.

I've tried the "force_board_rev=0x900093" bit again, and this time it worked. Dunno why it didn't yesterday.

Dave
by daveake
Wed Sep 21, 2016 8:06 pm
Forum: Camera board
Topic: Pi Zero not recognising camera
Replies: 3
Views: 757

Re: Pi Zero not recognising camera

Cheers. I've had a few emails with Gordon today about it so he was aware, but I don't know if he knew about your experience before. I did try your suggestion of editing config.txt, but raspistill produced a different error message (the one suggesting updating the firmware). I'll reply again when I h...
by daveake
Wed Sep 21, 2016 1:49 pm
Forum: Camera board
Topic: Pi Zero not recognising camera
Replies: 3
Views: 757

Pi Zero not recognising camera

I have 2 apparently identical Pi Zero V1.3 boards, one of which refuses to see an attached Pi camera, whereas the other is fine. When trying with raspistill I get .. mmal: Cannot read cameara info, keeping the defaults for OV5647 mmal: mmal_vc_component_create: failed to create component 'vc.ril.cam...
by daveake
Wed Sep 14, 2016 9:34 am
Forum: High Altitude Balloon
Topic: PI In The Sky - keeps ignoring the PISKY.txt file
Replies: 12
Views: 11906

Re: PI In The Sky - keeps ignoring the PISKY.txt file

> How do I parse the data into an image file ? You don't; dl-fldigi does. It creates jpegs locally - check the settings dialog to enable - and if it's online it uploads to the habhub server which puts the images on ssdv.habhub.org. > Where in the code can I change temporarly the APRS rate ? aprs.c >...
by daveake
Tue Sep 13, 2016 3:07 pm
Forum: High Altitude Balloon
Topic: PI In The Sky - keeps ignoring the PISKY.txt file
Replies: 12
Views: 11906

Re: PI In The Sky - keeps ignoring the PISKY.txt file

Yeah, the other one doesn't work very well. Can't do low baud rates, for a start.

Bluetooth doesn't have a great deal of use in a HAB, so it was an easy decision.

Dave
by daveake
Tue Sep 13, 2016 11:13 am
Forum: High Altitude Balloon
Topic: PI In The Sky - keeps ignoring the PISKY.txt file
Replies: 12
Views: 11906

Re: PI In The Sky - keeps ignoring the PISKY.txt file

On a Pi 3B you should be looking for 'ttyS0' in '/dev' and the soft link 'serial0' which should point to 'ttyS0'. 'ttyAMA0' is normally reserved for Bluetooth. Dave. Except that we need the proper serial port for PITS, hence (in the instructions) we load a devicemap to restore that port to the GPIO...
by daveake
Tue Sep 13, 2016 8:39 am
Forum: High Altitude Balloon
Topic: STICKY: PITS Support
Replies: 0
Views: 8808

STICKY: PITS Support

For post-sale support on Pi In The Sky software or hardware, please use one of the following methods rather than posting in this forum:
Dave
by daveake
Tue Sep 13, 2016 8:17 am
Forum: High Altitude Balloon
Topic: PI In The Sky - keeps ignoring the PISKY.txt file
Replies: 12
Views: 11906

Re: PI In The Sky - keeps ignoring the PISKY.txt file

Yes use the upuaut email; anything software-related gets forwarded to me, but Anthony does the first-line support. He forwarded your email to me last night and I replied to him this morning, saying that I'd answered you here. I don't recall the earlier email. If you think you have a special talent, ...
by daveake
Tue Sep 13, 2016 6:20 am
Forum: High Altitude Balloon
Topic: PI In The Sky - keeps ignoring the PISKY.txt file
Replies: 12
Views: 11906

Re: PI In The Sky - keeps ignoring the PISKY.txt file

OK, a few things to say here. First, for PITS support please use the official support email address - that way all those involved get to see it. Although I check this forum periodically, Anthony doesn't, so you should get a better and faster response that way. Second, the manual was updated weeks ag...
by daveake
Sun Sep 11, 2016 1:14 pm
Forum: High Altitude Balloon
Topic: Helium
Replies: 6
Views: 10230

Re: Helium

another one: http://theinspirationroom.com/daily/2014/helium-the-oscar-winner/ please use a somewhat more descriptive subject line next time so posters do not have to guess what you actually want! one word subjects are too short! Indeed. Next comment might be "those are UK suppliers and I'm in Uzbe...
by daveake
Sun Sep 11, 2016 8:18 am
Forum: High Altitude Balloon
Topic: Helium
Replies: 6
Views: 10230

Re: Helium

Go to advanced search