Receiver not receiving anything?

315MHz and 433MHz wireless connections are very commonly used by consumer electronics including weather stations, home automation remote controls, power consumption meters, car alarms, and also many DIY projects.
Post Reply
acherion
Posts: 3
Joined: Sat Nov 23, 2013 12:06 pm

Receiver not receiving anything?

Post by acherion » Sat Nov 23, 2013 12:29 pm

Hi everyone,

Arduino novice here. I had purchased the 433MHz version of this shield some time back to work with my LaCrosse weather station (I don't remember the model number, but it's a couple of years old and it comes with temperature sensor, wind direction, humidity detection and rain bucket). I had some spare time this weekend, so I decided to connect this shield to my Arduino UNO and give the program listing for the Weather Station Logger from the Practical Arduino book a go.

After I had hooked everything up and uploaded the sketch to my Arduino (after replacing all the BYTE-specific Serial.print() calls with Serial.write()), all worked well and I was getting data showing up in my Serial Monitor. Exciting!

However, after I disconnected it to try and get it connected and working with a PHP script that I wrote on my Linux box, I discovered that no data was being sent over the line from the Arduino anymore. Curious, I connected this back to my development machine (an iMac) and all I get when I power the thing up is "Weather Station Receiver has powered up". No more data is sent.

My weather station comes with its own LCD panel for data display, and the first time I tried the Arduino sketch out it updated almost at the same time as this LCD panel, but now the LCD panel is updating normally and the Arduino sketch isn't picking up anything. Both the LCD panel and the Arduino are located in the same room, sitting approximately 20cm away from each other.

I tried to retrace what physical changes I had made to my Arduino creation here between the time that I had it working and now, and the only things I could think of were:
  • I wrapped the antenna cable (it came supplied with the receiver shield) around an old plastic ball point pen barrel, and taped it on either end so that it didn't unravel
  • Physically removing the USB cable to transport it from one computer to another
I did a continuity test with my multimeter from one end of the antenna wire to the header pin on the receiver PCB and continuity is fine there, I am pretty sure the antenna wire is not damaged.

Have I damaged my Arduino and/or my receiver shield? I find it hard to believe that I had done anything physical to damage it.

I have tried to debug the sketch and reuploading by placing some strategically placed Serial.println() commands to see if perhaps the sketch is stopping abruptly without any error message. I added a line in the Init_Ports() subroutine and another in Init_RF_Interpreters() and they show up in the Serial Monitor, but still no data. I changed the characters to print out from blank spaces (in the comments about a blank separator line for every 2 seconds since last packet) to characters like '.' and '#', but none of these characters appear. I added an else construct to compliment the line "if( (ulICP_Timestamp_262_144mS - ulWSR_LastTimestamp_262_144mS) > 8 )" but it just spewed out heaps of characters into Serial Monitor (which then crashed). The timestamp is not incrementing for some reason.

I also noticed that there is a call to RED_TESTLED_ON() in Init_RF_Interpreters() but when the sketch is running on the Arduino the red LED never turns on. I can't find any call in the sketch to RED_TESTLED_OFF() or RED_TESTLED_TOGGLE() either, so I am perplexed as to why the red LED never turns on (the green one is lit all the time, as is the blue power LED).

I also don't understand why defining DEBUG prints no new information in Serial Monitor. How much debugging has been considered in this sketch?

I tried starting from scratch and redownloaded the code from GitHub, made the changes to Serial.write() and then just upload to the Arduino, and I still get the same output.

Apologies if I am asking insane or muddled questions, I am a web developer by trade and just wanted to try something new.

I have added a link to my sketch here: http://pastebin.com/QXdW7vRk All my changes have been in the main .ino file, and I haven't changed anything in the .h file.

Thanks
— acherion

acherion
Posts: 3
Joined: Sat Nov 23, 2013 12:06 pm

Re: Receiver not receiving anything?

Post by acherion » Sun Nov 24, 2013 12:54 am

OK so I moved to a completely different computer (Windows this time) and in a completely different room, which incidentally is physically closer to the weather station, and the Arduino is now reporting stats from the weather station to the Serial Monitor. I'll chalk this one up to an environment issue ;)

I also understand now that DEBUG is to debug the data coming in from the weather station, and although useful for troubleshooting, doesn't accommodate troubleshooting whether you are getting a signal from the weather station or not in the first place.

angusgr
Freetronics Staff
Freetronics Staff
Posts: 853
Joined: Tue Apr 09, 2013 11:19 pm
Location: Melbourne, Australia
Contact:

Re: Receiver not receiving anything?

Post by angusgr » Mon Nov 25, 2013 9:46 pm

Hi acherion,

I'm glad to hear you got it working. I noticed you mentioned:
acherion wrote: I wrapped the antenna cable (it came supplied with the receiver shield) around an old plastic ball point pen barrel, and taped it on either end so that it didn't unravel
When you say wrapped, the antenna wire is now a spiral (helix) and no longer straight? The wire as supplied is really intended to be used straight as a monopole antenna, not a helical antenna. This may be the reason for the reduced range (if you're still curious, it could be worth unravalling it again and seeing if the range increases back to what you were previously seeing.)

acherion
Posts: 3
Joined: Sat Nov 23, 2013 12:06 pm

Re: Receiver not receiving anything?

Post by acherion » Tue Nov 26, 2013 4:05 am

angusgr wrote:When you say wrapped, the antenna wire is now a spiral (helix) and no longer straight? The wire as supplied is really intended to be used straight as a monopole antenna, not a helical antenna. This may be the reason for the reduced range (if you're still curious, it could be worth unravalling it again and seeing if the range increases back to what you were previously seeing.)
Yes, it looked like a pig's tail all spiralled up. I tried straightening it as much as I could but it's still a little curly.

As I was previously powering up the Arduino via USB, I tried again with a wall-wart power supply (output 12V DC, 1.7A) and the signal seems to receive much better, so I figured it's also a power supply issue, which makes sense in my head.

I'm planning on getting another Arduino, probably the Etherten, so that I can send the data from my Arduino over the network in my house, rather than have the Arduino tethered to a PC -- where I want this creation located in my house is in a unique position where there's an ethernet port and power point available, but it's not practical to have a PC there to receive the Arduino information.

I found through my testing that the signal was being picked up acceptably via the Arduino, but the wall wart I was using was getting incredibly hot. I'm an electronics n00b (did a bit of electronics theory in high school) and figured that I should try and aim for a wall wart with different voltage / amperage, but I'm not sure which way I should go.

I want strong signal reception but a cooler running wall-wart. Should I go for a lower amperage (I've read that even 1A is more than plenty to run this stuff) or should I go lower voltage?

I also want to get a project case to house all this stuff in, would you know angusgr if I can house the antenna inside this case too, perhaps loosely looped inside? Or does it need to be sitting outside this case? FWIW, the case will most probably be plastic.

Thanks for reading/replying.

angusgr
Freetronics Staff
Freetronics Staff
Posts: 853
Joined: Tue Apr 09, 2013 11:19 pm
Location: Melbourne, Australia
Contact:

Re: Receiver not receiving anything?

Post by angusgr » Tue Nov 26, 2013 4:57 am

acherion wrote: As I was previously powering up the Arduino via USB, I tried again with a wall-wart power supply (output 12V DC, 1.7A) and the signal seems to receive much better, so I figured it's also a power supply issue, which makes sense in my head.
That does sound possible, glad to hear that helped.
acherion wrote: I found through my testing that the signal was being picked up acceptably via the Arduino, but the wall wart I was using was getting incredibly hot. I'm an electronics n00b (did a bit of electronics theory in high school) and figured that I should try and aim for a wall wart with different voltage / amperage, but I'm not sure which way I should go.
If all that's connected was the Arduino with the 433RX shield, I'm surprised it got particularly hot. I think it may be less due to the output rating of the power supply, and more due to the internal efficiency (or lack of efficiency) of the supply or possibly a fault with it. Alternatively something in your circuit is consuming more power than it should.

A supply outputting anywhere from 7V - 12V and 500mA should be plenty. A higher current rating, say 1A or more, would also be fine - the current rating can be higher than required with no problems.

However keep the voltage as low as you can find above 7V (this means less heat is dissipated at the device end, although it shouldn't make much difference at the wall wart end.)
acherion wrote: I also want to get a project case to house all this stuff in, would you know angusgr if I can house the antenna inside this case too, perhaps loosely looped inside? Or does it need to be sitting outside this case? FWIW, the case will most probably be plastic.
In a plastic case you should be fine, however you'll still get the best reception if you keep the antenna wire as straight as possible inside. You may want to consider drilling a hole in the case and letting it dangle out.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest