Go to advanced search

by sparkyhall
Sat Apr 01, 2017 4:37 pm
Forum: General discussion
Topic: Soldered USB dongle won't work without cable connected
Replies: 5
Views: 2013

Re: Soldered USB dongle won't work without cable connected

Actually it's not at all weird. There is a lot more to connecting high speed data lines than just connecting them with a piece of copper wire, look up transmission line theory. The connecting cable has to have the correct characteristic impedance otherwise you get signal reflections due to impedance...
by sparkyhall
Thu Mar 16, 2017 8:54 pm
Forum: General discussion
Topic: One large 5 volt supply?
Replies: 26
Views: 5443

Re: One large 5 volt supply?

You need to think very carefully about potential fault conditions before doing something like this. If, for example, you connect 10 PiZero to a 5V@20A PSU, a fault such as a short circuit in a connected USB device may well cause a fire due to severely overloaded cables and PCB tracks. Clearly using ...
by sparkyhall
Sat Jan 28, 2017 10:42 pm
Forum: General discussion
Topic: Power issue on PI3
Replies: 10
Views: 2516

Re: Power issue on PI3

The meanwell 5V 5A PSU you linked to in your first post has a small voltage adjuster next to the two pin output connector (labeled SVR1 in datasheet), according to the datasheet this allows you to adjust the output voltage between 4.75V and 5.5V. Ideally you want to set the output to 5.1V with a mul...
by sparkyhall
Fri Dec 23, 2016 10:01 am
Forum: Weather station
Topic: Weather Station Components
Replies: 21
Views: 8308

Re: Weather Station Components

You can find details of how to connect the sensors in this thread: https://www.raspberrypi.org/forums/viewtopic.php?f=112&t=142570 I also put some of my build info, including a schematic on github: https://github.com/sparkyhall/DIY-Raspberry-Pi-Weather-Station My home build has been running with...
by sparkyhall
Thu Nov 17, 2016 12:57 pm
Forum: General discussion
Topic: Stepper Motors and the L293D
Replies: 12
Views: 4022

Re: Stepper Motors and the L293D

If it is not a sofware issue then it may be an electrical noise issue. Here are a few initial thoughts: -The L293D is a 5V logic device so if you are driving directly from the Pi GPIO you will have reduced noise immunity. -Have you kept the L293D 5V logic supply seperate from the motor supply? -Have...
by sparkyhall
Tue Nov 08, 2016 7:15 pm
Forum: Weather station
Topic: Ambient Temperature +5 degrees
Replies: 33
Views: 6729

Re: Ambient Temperature +5 degrees

Does Figaro TGS2600 include heater? Most of gas sensor need to heat up before you can get reliable readings. If so ... that is why only ds1820b give reliable readings. Yes the TGS2600 does include a heater and I suggested this may be the problem back in post 9 of this thread: https://www.raspberryp...
by sparkyhall
Sat Nov 05, 2016 10:21 pm
Forum: General discussion
Topic: rpi3 resistor help
Replies: 19
Views: 3563

Re: rpi3 resistor help

I just measured R31 as zero Ohm on my Pi3.
by sparkyhall
Sat Nov 05, 2016 8:58 am
Forum: Weather station
Topic: Ambient Temperature +5 degrees
Replies: 33
Views: 6729

Re: Ambient Temperature +5 degrees

DS18B20 is most accurate. In those two other temp sensors are only used to correct main purpose readings. While this may be true the HTU21 is supposed to be within 0.4 degrees over 5 to 60C so this doesn't account for the errors people are seeing here. On my home build version of the weather statio...
by sparkyhall
Sun Oct 30, 2016 1:05 pm
Forum: General discussion
Topic: Uninstalling programs?
Replies: 9
Views: 2802

Re: Uninstalling programs?

I think when the OP says he installed windows Iot he means "Windows IoT" which has nothing to do with linux. I'm afraid I have no idea how that installs though.
by sparkyhall
Sun Oct 30, 2016 9:00 am
Forum: General discussion
Topic: Putting Up A Web Page: "Web Server"?
Replies: 31
Views: 5720

Re: Putting Up A Web Page: "Web Server"?

As others have said you do not need to install Apache.

I have recently started using "cherypy" for one of my python projects and it works very well. I did install a more recent version of cherrypy through pip rather than use the one available through apt-get.
by sparkyhall
Mon Oct 17, 2016 6:21 pm
Forum: General discussion
Topic: SSH and Jessie Lite?
Replies: 3
Views: 1848

Re: SSH and Jessie Lite?

I installed Jessie Lite only last night and ssh was already enabled.

What model Pi do have and how are you connecting, wi-fi or ethernet?
by sparkyhall
Thu Oct 13, 2016 6:18 pm
Forum: Weather station
Topic: Connecting wind and rain sensors (build your own station)
Replies: 190
Views: 90133

Re: Connecting wind and rain sensors (build your own station

Yes you can connect different sensors to the same data and clock pins with I2C, although the clock speed will be limited to the slowest device. You do have to make sure that each sensor has a unique address though. Some have a single pre-programmed address, some have one or more pins that you can ti...
by sparkyhall
Mon Aug 15, 2016 7:35 pm
Forum: General discussion
Topic: Expander Board.
Replies: 3
Views: 787

Re: Expander Board.

by sparkyhall
Mon Aug 08, 2016 9:25 pm
Forum: General discussion
Topic: Need someone battery knowledge
Replies: 2
Views: 738

Re: Need someone battery knowledge

It is not possible to confirm with the information provided, assuming you plan to connect the TFT interface board directly to the battery. I say this because the TFT interface board doesn't give a input voltage tolerance, it simply states 12V@1000mA input. The battery output voltage range is 10.8V -...
by sparkyhall
Tue Aug 02, 2016 7:21 pm
Forum: General discussion
Topic: EMC emission at 200mhz
Replies: 31
Views: 11042

Re: EMC emission at 200mhz

You haven't stated if you had HDMI connected with your marginal pass or what you are testing too? The quality of the HDMI cable (ans USB for that matter) will more the likely have a big impact on EMC performance, you need a cable that is properly screened. I'm afraid I can't recommend a good cable, ...
by sparkyhall
Mon Jul 25, 2016 9:49 pm
Forum: Weather station
Topic: Solar Radiation
Replies: 22
Views: 15391

Re: Solar Radiation

Now, the problem: the VML is giving me something like 40% less UV index than what i was expecting. I intended the light bulb to be more or less completely transparent to UV, am i wrong? what am i missing? I believe pond UV filters use transparent quartz because normal glass blocks too much UV, my g...
by sparkyhall
Sun Jul 24, 2016 8:11 pm
Forum: Weather station
Topic: Weather Station Web Time Offset?
Replies: 5
Views: 1705

Re: Weather Station Web Time Offset?

Adding timezone: "browser", under var flot defaults to var/www/html/demo/index.html should do it:

Code: Select all

      var flot_defaults = { 
        xaxis: { 
           timezone: "browser",
           mode: "time",
This tells flot to use your local browser time rather than utc.
by sparkyhall
Fri Jul 22, 2016 8:20 am
Forum: Weather station
Topic: Made a dashboard for the RPi Wx Station
Replies: 40
Views: 8941

Re: Made a dashboard for the RPi Wx Station

I'd like to add a current radar for "your" location to the dashboard. The equivalent in the UK is the "Met Office", lots of info in their web site for example a rain radar map: http://www.metoffice.gov.uk/public/weather/observation/rainfall-radar#?map=Rainfall&fcTime=1469131...
by sparkyhall
Thu Jul 21, 2016 2:37 pm
Forum: Weather station
Topic: Ambient Temperature +5 degrees
Replies: 33
Views: 6729

Re: Ambient Temperature +5 degrees

This issue has come up before: https://www.raspberrypi.org/forums/viewtopic.php?p=971836#p971836 Although I don't have the official weather station my suspicion is that the heater inside the TGS2600 (air quality sensor) is to blame. One way to reduce the impact of this is to blow air over the board ...
by sparkyhall
Tue Jul 12, 2016 7:36 pm
Forum: Weather station
Topic: Made a dashboard for the RPi Wx Station
Replies: 40
Views: 8941

Re: Made a dashboard for the RPi Wx Station

You've got a RPi2, so you can install Chromium. https://www.raspberrypi.org/forums/viewtopic.php?p=818455#p818455 Well, actually I have 3x2Bs, 1x3B, 2xBs, 2xAs and a zero so plenty of Pi here. I tend to use my Pi's headless so I was simply pointing this out for others. Anyhow thanks for taking the ...
by sparkyhall
Tue Jul 12, 2016 7:10 pm
Forum: Weather station
Topic: Questionable wind speeds
Replies: 14
Views: 3191

Re: Questionable wind speeds

The calibration factor in "interrupt_daemon.py" is wrong and should be 2.36 not 1.18. I reported this some time ago in the DIY build thread here: https://www.raspberrypi.org/forums/viewtopic.php?p=972369#p972369 This results in the wind speed being reported at half speed. Here is a copy of...
by sparkyhall
Mon Jul 11, 2016 11:43 am
Forum: Weather station
Topic: Made a dashboard for the RPi Wx Station
Replies: 40
Views: 8941

Re: Made a dashboard for the RPi Wx Station

joshcarroll wrote: Are they animated so that the needle naturally moves to the next value when an update is processed?
Indeed they are. The only downside I have found so far is that they do not seem to work properly in the Raspian epiphany browser.

Chris
by sparkyhall
Sun Jul 10, 2016 8:15 pm
Forum: Weather station
Topic: Made a dashboard for the RPi Wx Station
Replies: 40
Views: 8941

Re: Made a dashboard for the RPi Wx Station

Nice work joshcarroll. I have been trying the "steelseries" gauges with your code: https://github.com/HanSolo/SteelSeries-Canvas These gauges have many options, including a traditional thermometer style for temperature, min/max and trend indicators. Here is the results of my efforts so far...
by sparkyhall
Wed Jun 29, 2016 12:15 pm
Forum: Weather station
Topic: Very wrong readings.. worked before
Replies: 8
Views: 1884

Re: Very wrong readings.. worked before

It looks like your pressure reading is rather erratic as well, this may suggest something else is wrong like an intermittent connection somewhere. It may be worth simply unplugging everything and plugging it back in. For the record the last four pressure readings I got from your web site were 956, 8...
by sparkyhall
Tue Jun 28, 2016 11:38 am
Forum: Weather station
Topic: setup and demo site
Replies: 39
Views: 5320

Re: setup and demo site

You can tell flot, the graph plotting program, to use your browser time instead of UTC. To do this you need to edit /var/www/html/demo/index.html and add "timezone: "browser"," in var flot_defaults as follows: var flot_defaults = { xaxis: { timezone: "browser", mode: &q...

Go to advanced search