Tagged: digital radio

SignalsEverywhere: Build an RTL-SDR Based OP25 Radio Scanner with a Mobile Control Head Android App

Welcome back to Sarah from the SignalsEverywhere YouTube channel who has recently returned to producing videos from a hiatus. In her latest video, Sarah shows off her new OP25 Mobile Control Head Android App which allows you to implement a full P25 digital radio scanner at a fraction of the cost of a commercial digital scanner. In the past, Sarah had released a similar application written for the Raspberry Pi but has decided to shift her focus to writing an equivalent Android app that is less clunky and can be deployed for a lower cost. 

The app controls and displays information from the OP25 software that runs on a Raspberry Pi with RTL-SDR connected. It works by using a server application on the Raspberry Pi that manipulates the OP25 instance and its configuration files.

Sarah writes:

The application is a wrapper for OP25 that uses a raspberry pi and an android device to provide users with a mobile control head for their OP25 P25 scanner setup. Currently it's just a basic application but I'll be adding features like automatic site switching, etc.

OP25MCH: https://github.com/SarahRoseLives/OP25MCH

There is also a separate application I call the OP25Display which is just a display for a users existing OP25 instance.

OP25Display: https://github.com/SarahRoseLives/op25display

Build Your Own Digital Radio Scanner With OP25 Mobile Control Head App

Titus II SDR Updates

Over on the swling.com blog we’ve seen news of an update regarding the PantronX Titus II SDR. The last update we had was in January. Swling.com contributor Richard Langley writes:

There was a segment on the latest episode of AWR’s Wavescan (9 April 2017) about the Titus II DRM receiver recorded during the recent HFCC meeting in Jordan. In it, it was stated that the shipment of the first 1500 units was expected at the end of March or by the first half of April. Included some discussion of added shielding to prevent digital noise and the high-sensitivity of the receiver compared to other DRM units. 

Head over to the swling.com post to listen to the Wavescan podcast announcement,

The Titus II is an Android Tablet + SDR combination that is due to be released in the near future. Its main purpose is for reception of Digital Radio Mondiale (DRM) which is a digital broadcasting medium used on the HF frequencies, which somewhat replaces standard short wave AM radio. The Titus II hopes to be one of the first low cost receiver solutions for this market and as a wideband SDR it should work for many other applications too. From the advertised frequency range of 100 kHz – 2 GHz we speculate that it will be using the Mirics SDR chipset, which is the same chipset as used in the SDRplay. The target price is under $100 USD.

The Titus II Portable SDR
The Titus II Portable SDR

An Update on the PatronX Titus II

Back in September 2016 we posted about the PatronX Titus II portable software defined radio which appears to currently be on its way to beginning production. It is a portable Android tablet based SDR, which we speculate is using similar chips to the SDRplay RSP with its 100 kHz to 2 GHz tuning range. The price goal is set to be under $100 USD.

Currently it is available for ‘pre-order’ on the HFCC website, although what they call a pre-order is actually just an expression of interest, and no payment is required.

Today over on the SWLing post blog we’ve seen an update. They write:

As you can imagine the response to Titus has almost been overwhelming! Pre-orders far exceeded our imagination and excitement from broadcasters has been very loud. DRM and digital broadcasting seems to be reinvigorated with Titus in 2017. I think we really broke the price barrier that most everyone has been dreaming of and provided the flexibility that has held back the cause.

As posted on http://hfcc.org/delivery/receivers.phtml

‘Update on availability received from PantronX: “We have been overwhelmed with the response to Titus with orders and request – coupled with an early Chinese New Year that the pre-production date has slipped a bit. Please be patient as we work with our suppliers and add more functions.” ‘

We are doing all we can to push – Chinese New Year is a crazy time – the factories are shut down for 3 to 4 weeks and as you can imagine the stress prior to and the performance after.

Hopefully in the next couple of weeks our http://titusradio.com/ website will undergo a much needed update. So much to do – but we are making good headway.

The Titus II Portable SDR
The Titus II Portable SDR

Titus II Expression of Interest Form Available Now

Earlier in the month we posted about the Titus II SDR. The Titus II is an upcoming full SDR solution, including a wideband 100 kHz to 2 GHz SDR, Android tablet with touchscreen and speakers. They write that the price will be under $100 USD.

The High Frequency Co-Ordination Conference (HFCC) is a group active in informal co-ordination of frequency channels used in short wave broadcasting. The HFCC appear to be helping with the release of the Titus II, and they now have an online expression of interest form available on their Titus II page. The form is labelled “Pre-order”, but there is no payment or contract present, so it is more like an expression of interest. They write:

The Titus II – an Android tablet computer with wideband SDR receiver – was unveiled for the first time at the B16 HFCC/ASBU conference in Miami, Florida, 22-26 August 2016.

The receiver has been the result of cooperation between Trans World Radio (TWR) and PantronX.

The HFCC is assisting in collecting the demand/pre-orders.

Availability: Pre-production batch – 4Q/2016, regular production – 1Q/2017

Price: Under 100USD plus shipping and local duty/taxes not included

Payment methods: Wire transfer for larger quantities, PayPal works too, but the buyers would need to add PayPal bank fees

An initial order sufficient to start the production has already been placed and production will start irrespective of the amount pre-ordered via this page. Pre-order is not binding and you are NOT asked to send any advanced payment or credit card number to secure the pre-order.

titus-2-big

[First seen on swling.com]

The Titus II Complete SDR Solution

Recently we’ve heard news of a new portable SDR called the PantronX Titus II which is currently in development. The receiver is a full SDR solution, including the computer, speakers, antenna and SDR all in a single boombox styled enclosure. The computer appears to be based on an Android tablet, and comes with a Quad-core ARM A53 @ 1.2 GHz CPU, 1 GB RAM, 8 GB Flash memory, 7″ TFT screen, touch screen, 5 watt stereo audio, li-poly battery. HDMI output, microUSB OTG connector, WiFI/Bluetooth connectivitiy as well as having an optional camera. 

The frequency range extends from 100 kHz to 2 GHz, and the built in software is capable of decoding AM/FM/SSB and DRM. Since it is essentially an SDR with an Android tablet, it should also be capable of decoding any other signal, as long as software decoders are written for it. We are unsure what SDR is used on the inside, but judging by its frequency range we speculate that it may be the same Mirics chips that are used inside the SDRplay RSP.

Rumour currently has it from word of mouth of the developers that this unit will priced “well below $100 USD”.

The promotional PDF can be found here.

titus-2-big

RTL-SDR Tutorial: Decoding Digital Voice (P25, DMR, NXDN, D-STAR) with DSD

The RTL-SDR software defined radio combined with SDRSharp and a program called “digital speech decoder” (DSD) can be used as a radio scanner to easily and cheaply listen to unencrypted digital radio voice conversations.

Digital radio voice communications are becoming more commonly used in the radio spectrum. This is due to the various improvements offered over traditional analogue voice radio systems. Unfortunately for radio scanner hobbyists, digital radio is difficult to receive, as special radio scanners which can be expensive are required to decode the digital signal. Additionally, digital radio systems can be encrypted making it impossible for communications to be decoded by a hobbyist. However, most users of digital radio do not bother to encrypt their systems as it can introduce lag, monetary expense and extra battery drain in portable radios.

The most common digital speech codec is APCO P25, which DSD is able to decode. DSD is also capable of decoding other common digital codecs such as DMR/MOTOTRBO, NXDN, D-STAR and ProVoice.

Super cheap software defined radios such as the RTL-SDR can be used to decode these digital voice communication signals instead of expensive radio scanners. While this tutorial is aimed at the RTL-SDR, other software radios such as the Funcube dongle, Airspy, HackRF and BladeRF will also work. Hardware radios with discriminator taps connected to a PC may also work.

Examples of DSD Decoding Digital Voice with RTL-SDR as a Radio Scanner

YouTube user Geoff Wolf shows a video where he uses RTL-SDR as a police scanner to listen to public safety P25 digital radio using DSD, SDRSharp and virtual audio cable.

RTL-SDR: Decoding P25 Phase I QPSK with DSD and SDR#

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