By: Brian Andrews

I’ve been using my cellphone as a telemetry receiver for several years now.  Not every phone if capable, but many are, maybe even an old one you are not using anymore.  You don’t need cell service to use it.  This is perfect to combine with a CheapBeep transmitter.  It can do all telemetry frequencies currently in use.  So what are the phone requirements?

  1. Android
  2. OTG (on the go) capable. If you have a USB OTG cable, plug up a mouse or something and see if it works.
  3. A good battery.  Running as a receiver takes power and a bad battery will not put out enough current.

The parts listed below are what I used and where I got them.  You may be able to source them cheaper.  I bought what I did because the companies backed them up and I’ve had good experiences with them.  What parts do you need?

  1. OTG cable –
    1. If you have a USB-C connections: https://www.amazon.com/gp/product/B01COOQIKU/
    2. If you have a Micro USB connection (this is a right angle version): https://www.amazon.com/gp/product/B00GM0OZ4O/
  2. SDR – https://www.amazon.com/gp/product/B01B4L48QU/
    1. This one is small and powerful
    2. Low heat
    3. Low power consumption
  3. BNC female to MCX male pigtail.  I use a right angle one to make it more low profile.  6 inches long is normally good. https://www.amazon.com/gp/product/B00CSCTU40/
  4. An antenna at the frequency you want.  I make my own so there is no link.  I used a vent clip cell phone holder to easily attach my phone to my antenna.

The app you choose will determine what it looks like.  Some are easier to use than others.  You will have a learning curve working with any of them. The one I use, I turn on auto gain while I’m running an Omni so I can drive around and locate a signal, then I manually adjust the gain when I hook up my directional antenna.  Here are the two apps I recommend for most users. 

  1. SDR Touch – the software to display.  I prefer the paid version for waterfall and squelch features but they are not required.
  2. RTL-SDR Driver – This is the driver necessary to make the SDR work with your phone.  This is required no matter what SDR app you choose.

Remember, this does not work on all phones so don’t order anything unless you are sure it will or are not worried about the money.

Tested phone list:

  1. Amazon Fire 7″ Tablet
  2. Google Pixel
  3. Motorola G4
  4. Motorola Moto X
  5. Motorola Moto Z Play
  6. Samsung Galaxy S6
  7. Samsung Galaxy S7
  8. Samsung Galaxy Note 4

Phones it did NOT work on for me:

  1. Motorola Moto G 3rd edition
  2. Motorola Moto E

If you find it works on a phone, please send me an email with the model so I can add it to the list.  [email protected]