Connecting external device


So I’m an ecologist who’s also into bats. You could perhaps understand my delight that nowadays you can connect an external ultrasound microphone to your smartphone, to use it as a bat detector. I’ve currently borrowed one of these devices from a friend of mine (see link to it below), but I cannot make it connect to my FP2. The problem shouldn’t be the device itself, as it works when I connect it to my laptop.
Does anyone know how I can make my FP2 connect to the microphone? Bluetooth isn’t an option, it needs to be connected via USB. The device works on Android.

Looking at the connecting cable pictured for the device you might need a USB-OTG adapter from the phone’s micro USB port to USB-A.

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Just to get this straight: are you able to properly connect the device physically to the FP2?

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@AnotherElk & @robbert.f: yes, the cable (which is brand new) properly connects between the FP and device. Connecting the device or the FP to my laptop (with different cables that connect to a usual USB port) doesn’t give any issues. So somehow the device and FP don’t seem to be able to connect between one another. Could this perhaps be solved via a setting or something?

Are you sure you’re using a data cable and not just a charging cable? Can you successfully connect your phone’s storage to your laptop with the same cable?

The page you linked to states that the device requires the phone to be able to record at 384kHz - I don’t know much about that sort of thing, so I don’t know if the FP2 supports it. But it may be something worth looking into if it’s not a cable issue.


Yes, I would also agree to your statement.



If possible have a try and replace the provided cable of the microphone with another fitting cable and connect it to your computer.
These cables have a good availability although they are not so common anymore as the successor µUSB is also shifting already for USB-C.
Does it still work?
It could be that this delivered cable is specifically made for the device.
It could also be that it is manufactured and made as a USB OTG (on-the-go) adapter and the microphone therefore works with your friends phone.
Computers usually power any connected USB device, hence -> bus powered and the device is expected to operate with it.

Your FP2 can also handle OTG connected devices, but not every adapter (cable) will work as there are different USB implementations of how to enable different phones to give out power to the USB connector.
Actually to find a working adapter it’s more or less trial and error if not having someone who can custom build one specifically for your FP2. You could also search through this forum as there were other users in the past who already was into this OTG issue but also successful in finding a working adapter. Here some background.

At the end it’s still about charging the phone. Some can do both, charge while supplying power to the µUSB port. But I believe FP2 cannot, so you would be limited to your battery runtime.

I am not sure if you in any way have to enable the USB debugging mode in the developer settings.
Settings->scroll all down-Developer options(have to be enabled first)->USB debugging.

Sorry, I’ve been a bit busy with work. Thank you all for your replies, I’m going to try out your suggestions and let you know how it went.

Using a USB-OTG cable worked! Thank you all so much for the help!


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