Hi @eivholt, I’ve soldered the SMA connector on the board without removing the u.FL. It sits perfectly there… I just had to put my soldering iron to high temperature as the SMA seems o absorb all heat making very difficult for the solder to melt nicely.
Btw, I’m also having fun with my nodes, but I keep moving them from one project to another… might need a few more.
Cool, I’ll try leaving it on. I assume the u.FL doesn’t form a closed circuit as long as no antenna is connected to it. I can imagine the SMA absorbs a lot of heat. I don’t have a broad tip for my soldering iron so thanks for the heads up!
I am going to add a coin cell battery holder on some of my Whisper Nodes and see how it works out.
Just to confirm that it’s not necessary to desolder the u.FL connector. The SMA Edge will fit without creating any short.
In case anyone needs to desolder an u.FL or SMA, the best way is by using hot-air. Alternatively carefully destroying the component with a wire cutter and desoldering individual “legs” is the safest approach.
Thanks for the confirmation. I have done this successfully on two nodes so far. Is it possible to give any general comparison on using the supplied pcb-antenna as apposed to the SMA whip antenna with respect to energy consumption. This is probably a many faceted problem to answer but taken the scenario: I have my lora gateway (TTN GW) in my house and I want nodes no further than 15 meters from this point. I want my nodes to run on 3V coin cells. Are these two antennas even anything I should consider when optimizing energy consumption? I take it a “larger” antenna requires more energy to resonate, but at what order of magnitude? Downlink is not in use in this example. Snowy and wet scandinavian weather is a consideration as the antenna will be exposed.
I would appreciate any insight that could help me make the nodes last as long as possible. I am awaiting an oscilloscope and will perform some tests with the different antenna configurations but I suspect someone with deeper knowledge has already done this.
In general, the larger the antenna, the better it radiates, and thus you require less transmit power (and less battery current) to cover a given distance.
Those small ceramic antennas are not very efficient, compared say to a simple bit of wire, although the wire would be bigger of course.
You need to be careful with coin cells, you may find their voltage drops, perhaps significantly, when the node is transmitting. A scope is useful for checking this, a multimeter may not capture the change for short duration packets…
Its supposed to be powered by an ATMEGA328P and is ‘Arduino compatible’ so as long as you adjust the pin numbers to match any code for the Arduino UNO ought to work.
A Google search on ‘Arduino TTN node’ ought to find something.
I searched and found some examples.
I manage to make one compile and run in the whisper node but i didn’t got anything on the TTN console.
The output in the serial didn’t show any errors and it was:
Soldering that small thing wasn’t easy, i ended up making a bridge with solder. (its the same thing i quess)
Clearly it made a diference since i see in the serial monitor the node trying to send something:
I checked lmic radio type and its set to sx1276 so that should be ok.
I tryed both msb and lsb format in the keys.
But i still didn’t get any msg in the console.
I runned out of ideas…
Any sugestions?