Then how did I manage to damage it? I don't understand.
The antennas were soldered from the very beginning, I never used them without their antennas.
I have another Lora ra-01 and a ra-02.
But I don't have antenna for the ra-02. (I can't find it in any local store and can't wait till it comes from ebay)
RA-02 has a connector on the pcb for the antenna, looks like the connector of wifi antennas.
So, any idea how to connect an antenna?
That's probably an IPEX connector. Most anntennas have SMA connectors, so you need a IPEX to SMA wire, and an antenna designed for the frequency of your LoRa module.
If the spring antennas don't work I don't know how good your chances are that such an external antenna does work.
Why do you say that the spring antennas don't work?
I didn't say they don't work.
panoss:
Oh 4$$$$it!!! I did everything for this not to happen and it happened!
As I mentioned earlier, a track was by mistake, grounded. This track was connected to MOSI pin of the Lora.
Could this damage the RF?
I could not say.
But 'mistakes' in wiring, including forgetting even briefly, to fit an antenna when the device is transmitting have resulted in damadged modules here. The damadged modules normally work OK as receivers but have a very low RF power output so dont work very well as trasnmitters, the other symptom being extreme short range.
Try again with new modules that you are sure are wired correctly and have antennas fitted, for 434Mhz a 17cm bit of wire will do.
The one will always be receiver only. So, this can work ok? Without reduced range? (if the transmitter is ok ofcourse)
If I take (for the RA-02) an SMA Female to U.FL - 20cm adaptor like this one, would, only this, without anything else, be ok as an antenna?
Or maybe this one?
panoss:
The one will always be receiver only. So, this can work ok? Without reduced range? (if the transmitter is ok ofcourse)If I take (for the RA-02) an SMA Female to U.FL - 20cm adaptor like this one, would, only this, without anything else, be ok as an antenna?
Or maybe this one?
Yes, as I said the 'damadged' modules normally work OK as receivers and have no adverse affect on receive range. If you had looked at the SX127X data sheet you will see why.
And as I also suggested for the antenna , just use a simple bit of wire, easy to attach, difficult for it to be wrong. Whereas u.fl to SMA adapters (yuk) can easily go bad and antennas designed for other frequencies are a very bad idea also.
I often use a length of PTFE insulated wire for antennas, its very tough and does not snag easily.
Well, the problem is with the connector.
How shall I solder a wire on a such a connector?
I guess I have to solder it on the pin in the center, right?
I tried my third RA-01...As transmitter.
The same depressive result...a little better though...now they communicate at 15cm distance...instead of 10cm...
I 'm desperate... 
In my code I have it this way, if it's of any importance:
//LoRa.setPins(ss, reset, dio0)
//dio0 is optional, only needed for receive callback mode
LoRa.setPins(10, A0);
Hi,
Can you post some pictures of your projects please, so we can see you component layout?
Have you monitored the 3.3V at the Lora when transmitting?
Thanks.. Tom.. 
The voltage on Lora is always 3.6V (when transmitting and when not transmitting) I just measured it.
Have a look at the photo in the attachment, this is the transmitter, you can see the Arduino in the middle and Lora on the right.
Yes, I 'm using 3.3V arduinos.
The voltage on Lora is always 3.6V
That would appear to be a contradiction ?
Hi,
Have you tried making both the aerials stand up at right angles to the PCB?
What is the long brown thing on the pcb?
Tom...
ATmega328P can operate with up to 5.5V.
And Lora RA-01 up to 3.7V.
Ok, this one is taken with daylight, I hope it's clearer.
There's no brown part on the pcb, I think you are refering to the black pin header.
I put it for the case I want to expand it (connect a sensor, or an lcd screen).
One thing (I have mentioned before):
The two Arduinos work on different baud rate at the Arduino IDE 's Serial Monitor.
Transmitter, 19200 Baud rate.
Receiver: 9600 Baud.
Can this be a problem?
They are a little bit different, but both are 3.8V 8MHz.
You can see them in the attachment.
On the left is the transmitter, the blue one and on the right, the black one, is the receiver.
Hi,
Can you provide a "connected"version of you schematic please, this version is OK for PCB design but useless for troubleshooting.
I call it the "search a word" schematic because you have to do a search a word to find EVERY connection.
These diagrams do not show you how many points any pin is connected to.
A proper circuit with lines/wire connections is much easier to follow.
Tom..
OP Said they were using 3.3V Pro Minis but the schematic says 5V.
Connecting a LiOn\LiPo battery direct to the VCC of a Pro Mini and LoRa device is not something I would recommend.
srnet:
OP Said they were using 3.3V Pro Minis but the schematic says 5V.
It doesn't matter if they are named as 5V, it'a just a name, doesn't change anything.
srnet:
Connecting a LiOn\LiPo battery direct to the VCC of a Pro Mini and LoRa device is not something I would recommend.
If it's not fully charged (mine is at 3.6V), why not?
C2 is at the bottom side of the pcb, look at the attachment.
The two TO-220 are mosfets, the one will be used for reverse polarity protection and the other as a switch for the power on and off of the Lora.
They are not used in the circuit for now, they are off circuit even though soldered.
At the second attachment you can see the diagram with parts connected, I hope it's clearer now.
These are the connections:
Arduino_____Lora
D2_________DIO0
D7_________DIO1
D8_________DIO2
D10________NSS
D11________MOSI
D12________MISO
D13________SCK
A0_________RESET
