LDS01 with external Antenna

What exactly should be desoldered?

The antenne on the back-side off the pcb

Thanks for the good picture. Now I know how the Dragino LDS01 looks inside without opening it. To explain a little bit what you are seeing there around the antenna: C1 is a decoupling capacitor to block DC-components, C3-L6-C5 form a low-pass filter to suppress unwanted (higher) frequencies.
The antenna is connected to the point where C5 and L6 meet. This point should also be connected to the inner conductor of IPEX1. It is hard to see on the picture whether there is a connection or not. Just measure the resistance between the connection of the build-in antenna and the inner conductor of IPEX1. It should be abt. 0 Ohms.
You can buy ready-made adapter cables from IPEX to SMA. I would not try to build them myself.
Remark: You have to remove the internal antenna before you use the IPEX connector.

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Thanks!

I purchased some IPEX-SMA adapter cables (http://bit.ly/2Ys1W9i), and got a very significant improvement with the RAK 7200 moving to an external dipole (http://bit.ly/2YnrK6t), so I know the antenna upgrade can work. However, while I was able to remove the LDS-01 antenna, I was unable to connect the LDS IPEX connector to the antenna cable IPEX slot.

I assume it has something to do with the type of IPEX connector, but haven’t been able to find where the issue is. Any suggestions?

imho the antenna you purchased is a 1/4Lambda (monopol) and not a 1/2 Lambda (dipole) antenna. A 1/2 Lambda dipole should be abt. 0.15m long.
I don’t know why there is a problem with the IPEX-connector. I use some of these adapter-cables also for GNSS without any problems.

I added an antenna to my LDS01 u need a IPEX MHF4 connector. Its smaller than standard IPEX U.FL.

if you google “U.FL IPEX MHF4 auf RP-SMA 0,81 mm RF Pigtail” you will find some.

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There is no resistor to remove, however you will need to remove the internal antenna as the externally connected one would be connected in parallel to the existing antenna.
BTW, make sure to use an RP SMA antenna if you are using the suggested pigtails, otherwise no center pin connection will exists resulting in no antenna connection.

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My mistake, just removed the antenna and attached an appropriate external, and it works!

Thanks for the advice @kersing !!

Final report: I desoldered the internal antenna and attached the IPEX1 MHF4 connector - not the IPEX4, a slightly smaller diameter is necessary, different than Rak wireless - and it works great!

I am trying to get a signal on the other side of a forest for cottage security, and while the original was not providing a single return, I am consistently getting medium-strength ones on even a fairly small antenna upgrade!! I have 2 units and testing them side-by-side shows clear result. This was just a couple dollars (USD equiv) and minutes to desolder the antenna, so I’m quite satisfied!

The final step is to run a cable from the door (beneath a steel roof) to a pole to maximize link budget.

Thanks to all who provided input. Hopefully this saves someone else time avoiding wrong components.

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20210329_170836 (1)

Thank you for sharing your experience!

Your result remember me to continue my work for a custom enclosure.
I have made good experiences with new firmware (>1.2) and the AT+MOD=3 command.
With a 3D printed enclosure it is a small and cheap but reliable device with two simple reed switches.

can you elaborate what you mean by AT+MOD=3? It sounds like you are using the hardware for something other than open/close?

AT+MOD=3 add the possibility to report both inputs. The reed contact and the water leakage sensor.

Very good to know, thanks.

People are doing cool stuff with this hardware.

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I assume the MHF4 plugs into the socket on the LDS01 board.

How did you fit the SMA-socket into the LDS01 enclosure?
Can you please post a pic with cover removed?

Yes it plugs into the MHF4, and no it does not fit into the enclosure without some creative destruction: when the board is removed from the enclosure you will see plastic standoffs that elevate it; I used some needlenose pliers to snap those off and then the SMA fit just fine.

The device is installed out at the cottage now, but I could add another one and document it for a tutorial if people want I guess…

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Hi, I read this thread and now I would like to add an external antenna to my LDS01 as well. However, I am not sure about choosing the right cable.
I have this antenna: GSM, GPRS, UMTS, 3G, GPS, Wifi, Ethernet Market Telit, Wiznet, 2J Antenna, EBYTE, WİZNET, Jiashan, 4G, Bluetooth, Simcom and I would need a cable at least 80 cm long.
Can you advise please?

Use the same cable as TC1 did but 0.8m of length.

Thank you for the quick response. I tried to find such a cable, but I didn’t.
I found only 50cm long cables: SMA Female Jack Bulkhead to IPX IPEX U.FL MHF4 RF Pigtail Jumper Cable for PCI WiFi Card Wireless Router 0.81mm Rocheuk|Connectors| - AliExpress
If you know where to buy 80cm or more, please send a link.

After 30 seconds of searching:
https://m.de.aliexpress.com/item/4000023276376.html?trace=wwwdetail2mobilesitedetail