Frequent RTL-SDR.com reader Rodolfo recently wrote in to us wanting to share a portable RTL-SDR set up that he has produced. From the supplied photo the portable unit looks very robust and really well built. We hope that it will give inspiration to others wanting to make portable units as well. Rodolfo wrote:
Last year, a friend of mine in the telecommunication services industry, was talking to me regarding some kind of sporadic interferences he was getting in their devices, and asked if I can do something about it. I spend some days trying to figure a way to help him, as it was (and is) a good friend of mine. I seat in my library at home, and start to scratch some designs, based in rtl-sdr.com article published in 6 October 2014: “RASPBERRY PI RTL-SDR SPECTRUM ANALYSER SCANNER”. Some weeks later, I get the designs and get a good cup of coffee with him. After the second cup, and I get a “go” sign, and so it born a portable spectrum capture that I called “sapinho”, as my youngest son nickname. Just “for the record”, “sapinho” in Portuguese means a little frog – you can jump from place to place to scan the RF band.
So, the device is very simple, the great problem was finding the most small configuration possible, to meet the portable specifications:
- Raspberry pi ver. B;
- NooElec RTL Receiver;
- “FreqShow” python software.
- A pair of LM2596 DC-DC;
- 3.5 ‘’ TFT LCD Touch Screen for Raspberry Pi;
- 6VDc battery;
- Expandable antenna;
Trying to get the most of it, I put a wifi dongle, so that he can connect to a nearby hotspot, or get a “had oc” connection for remote control. There is a plug for charging the batteries, and two red leds (one for the charging , and the other for operation status). All of it was install in a 100 x 300 x 100 (mm) portable aluminum box.