Some Tests on our BCAM and BCFM Filters

Over on YouTube user ElPaso TubeAmps has uploaded a video showing his tests on our broadcast AM (BCAM) high pass and broadcast FM (BCFM) band stop filters. These two filters are designed to block broadcast radio signals which in some locations can be extremely strong. If they are very strong then they can overload your SDR which causes very poor performance, even on other frequencies.

Some possible solutions for reducing overloading include:

  1. Attenuation – reduce all the strength of ALL signals coming in.
  2. Increase SDR dynamic range – purchase a higher end SDR with more ADC bits as these can handle strong and weak signals coming in together much better.
  3. Filtering – reduce the signal strength on the problematic frequencies that are causing overload, or only allow your frequency of interest to pass.
  4. Antenna tuning – use a narrowband, directional and/or differently polarized antenna which reduces the unwanted signal’s strength.

In the video he uses his signal generator and a spectrum analyzer to analyze the output of the filters. His results closely match our VNA results which are posted on the BCFM and BCAM filter product release posts.

RTL-SDR 88-108 MHz Bandstop Filter & 2.6 MHz HPF Broadcast AM Filter Measurements

Tweet
Share
Reddit
Vote
Email

YouTube Tutorial on Setting up a Soft66IP RTL-SDR

Over on YouTube user Danny Shortwave And Radio DX has uploaded a video showing an overview and tutorial about setting up the Soft66IP RTL-SDR. The Soft66IP is a custom RTL-SDR that is made in Japan by JA7TDO. It is an RTL-SDR with upconverter and LNA built into a box together with an embedded computing platform. We’re not sure what the computing platform is, but it is likely to be something similar to a Raspberry Pi. The computing platform is then used to run an rtl_tcp server, and so via a network cable or WiFi connection the device can be accessed by a remote PC.

On the video Danny gives an overview on what the Soft66IP is, and what features it has. Then later in the tutorial he shows how to SSH into the Linux server on the Soft66IP, set it up for your local network, and then later how to connect to it from a remote PC.

How to setup Soft66IP for your Local Area Network with SDRSharper

Tweet
Share
Reddit
Vote
Email

Controlling an RC Car with RPiTX

RPiTX is a piece of software that you can run on your Raspberry Pi unit, which with no additional hardware turns it into a full radio transmitter, capable of transmitting FM, AM, SSB and other signals anywhere from 5 kHz to 500 MHz. Of course remember that the methods used to do this emit a lot of harmonics, so to be legal and safe filtering should be used on the signal output.

Over on Twitter Cyril‏ @kotzebuedog has been experimenting with RPiTX and his radio controlled toy car. From the videos and images, it appears that he’s used GNU Radio to create the required control signals which then transmits the data to the RC car via RPiTX. With this he’s been able to create a program to control his RC car with his computer gaming joystick.

Tweet
Share
Reddit
Vote
Email

Testing SSTV Transmission with the HackRF and Portapack

Last week we made a post about the HackRF Portapack, and gave some examples of it in action. Recently the furtek Havoc firmware for the portapack was updated, and it now supports SSTV transmission. Over on Twitter, Giorgio Campiotti‏ @giorgiofox has uploaded a video showing an example transmission in action.

In the video the HackRF with Portapack transmits a test SSTV image to an Elecraft K3 ham radio, which is linked to a PC. SSTV decoding software on the PC turns the data back into an image.

SSTV stands for ‘Slow Scan TV’, and is a method used by hams to send images over radio. Typically this activity occurs on HF frequencies. Sometimes the ISS transmits SSTV images down to earth as well to commemorate special events.

Tweet15
Share
Reddit
Vote
Email
15 Shares

ColibriNANO: A New 10 kHz to 500 MHz Direct Sampling Receiver

The ColibriNANO is a new software defined radio that is currently available for pre-order and is expected to be ready for delivery by the end of April 2017. The specs show that it is a direct sampling receiver (no tuner), which can receive from 10 kHz to 500 MHz in oversampling mode, and from 10 kHz to 55 MHz in standard mode. It uses a 14 Bit ADC which provides up to 110 dB’s of blocking dynamic range, and can run with a sampling rate of up to 3 MHz. The press release given to us reads:

New ColibriNANO SDR USB Receiver with a 14-bit ADC .01-500MHz

Kirkland, WA, USA —March 27 th , 2017 –

Vasily Vasiliev, Chief Hardware Engineer of Expert Electronics is pleased to announce availability of new ColibriNANO 0.01-500 MHz receiver in late April, 2017.

Notable features include the blocking dynamic range (BDR) ~110dB, native .01-55 MHz coverage with up to 500 MHz in oversampling mode, low pass filter (LPF) <60 MHz, full compatibility with HDSDR, legacy SDR#, and ExpertSDR2 software.

Supported platforms are Windows® XP-10, Linux and Web-client for HTML5 browsers.

No existing USB SDR receivers combine high sensitivity and broad dynamic range. Remote operation (TCP/IP) interface is built-in and offers plug-and- play solutions for Amateur, Commercial and Government applications.

For further information call (800)977-0448 or email [email protected]

https://www.nsiradio.com

Currently we see that the ColibriNANO is selling for $249.95 USD on the nsiradio.com website. We’ve also seen the following description on the sunsdr.eu website:

With the new ColibriNANO you will be able to enjoy LF, MW and Shortwave listening in many different ways. For example you can record the entire medium wave band using 1.5 MHz sampling rate, decode CW using CW skimmer, remote control the ColibriNANO by plugging it into our RPI server. There are an endless range of applications for this small SDR. All this in a tiny USB stick!

The ColibriNANO features a Texas Instruments ADS4145 14 bit direct sampling ADC and a built in low 55 MHz pass filter that can be bypassed to receive signals up to 500 MHz (external filters  like the our 2m filtered preamp recommended).

CW skimmer and Skimmer With the external ExtIO library the ColibriNANO can be used with third party software like HDSDR etc.

This is not a cheap USB dongle found on Ebay, this high quality SDR receiver is developed by Expert Electronics and features a sturdy aluminium chassis, ESD protection, USB 2.0 interface and a quality SMA antenna connector.

Best of all, the ColibriNANO travels in your pocket and only needs your computer and an antenna! Its the ultimate portable SDR receiver!

Software support

  • ExpertSDR2
  • CW Skimmer
  • Skimmer Server
  • Third party software using ExtIO library

Specifications

  • Receiving bandwidth: 0.1 – 55 MHz
  • Oversampling receiving: 0.1 – 500 MHz
  • Blocking Dynamic Range (BDR): 110 dB
  • Sensitivity: 0.05 uV at 20M band, preamp = 0
  • IMD3 Dynamic Range: 95 dB
  • ADC resolution: 14-bit @ 122.88 MHz
  • Sample rate: 48, 96, 192, 384, 768 kHz and 1.5, 3.0 MHz
  • IQ resolution: 24 bit (16 bit at 1.5 and 3 MHz sample rates)
  • RF Input: (SMA connector, up to 15kV ESD protection)
  • Preamp range: from 31.5 up to +6 dB with 0.5 dB steps
  • Operating temperature: -10°C to 60°C
  • Dimensions: 90х25х17mm
  • Weight: 0.043kg

It looks like that this receiver may compete somewhat with the also upcoming Airspy HF+. The Airspy HF+ claims similar specs including a frequency range of 0 – 270 MHz, 14 Bit ADC and 108 dB blocking dynamic range. But the target price for the HF+ is below $200 USD.

Tweet
Share
Reddit26
Vote
Email
26 Shares

New Outernet Hardware “Dreamcatcher”: An RTL-SDR with Embedded Computing Hardware

Over on the Outernet forums Outernet CEO Syed has just released pictures of the latest upcoming Outernet receiver called “Dreamcatcher”. The new receiver is an RTL-SDR, LNA, filter, and embedded Linux capable computing hardware all on board a single PCB. The full specs are pasted below:

  • L-band SAW filter (1525 – 1559 MHz)
  • Two-stage L-band LNA with 34dB gain
  • 0.5 PPM TCXO
  • RF bypass for tuning from 24 – 1600 MHz – use as a regular RTL-SDR!
  • USB ports
  • GPIO forest
  • UARTs, I2C, SPI headers (unpopulated) for driving external hardware
  • Two microSD card holders – for boot and storage!
  • 1 GHz CPU
  • 256 MB RAM Now 512 MB RAM
  • USB wifi dongle (not shown) – STA+ AP mode capable!
  • Lots of LEDs! and Switches!
  • microUSB OTG
  • microUSB power port
  • Audio In/Out
  • Speaker with 1.4 W integrated audio amplifier
  • Fully mainline (4.10) Kernel and (2017.01) Uboot support!
    *** JST battery is being removed

On the Roadmap:

  • armbian/debian support

This is a fully-integrated SDR receiver – RF frontend, SDR, Compute, Wifi – Everything!

Outernet is an L-band satellite service that aims to be a download only “library in the sky”. Currently they are broadcasting from Inmarsat and Alphasat geostationary satellites which can be received from almost anywhere in the world. We have a tutorial on receiving and decoding their signal here. Every day almost 20 MB of data is sent down, and this includes data like news, weather forecasts, APRS, wikipedia articles, books and more. In the future you will be able to pay to upload private files or messages. This could be useful for sending messages to people isolated from cell phone reception, or for operating remote hardware.

Previously Outernet sold a DIY version of their receiver which included an RTL-SDR V3 or E4000 dongle, LNA+filter, a C.H.I.P embedded computer, and a patch antenna. Recently they have changed to their custom RTL-SDR hardware which is called the “SDRx”. The SDRx includes the RTL-SDR, LNA and filter on a single PCB. Over time it seems that they are moving in the direction of integration of all components onto a single PCB and this can be seen in the Dreamcatcher which now also includes the computing hardware. This is especially good news as the $9 C.H.I.P computing hardware has been almost impossible to acquire since its release.

The Dreamcatcher looks to be also not just useful for Outernet, but also for general projects that can be done on embedded hardware as there is a port which bypasses the L-Band filter.

Back in 2014 we posted about the XiOne. This was also to be an RTL-SDR and computing hardware built onto the same PCB. It would have been controlled via a WiFi connection and apps on a smart phone/tablet. Unfortunately the XiOne Indiegogo crowdfunding campaign never reached its target so the project faded away. The Dreamcatcher is somewhat similar in that both are RTL-SDRs with onboard computing hardware and WiFi connectivity.

The Dreamcatcher is not yet for sale, but it is currently under production. From the looks of the discussion on the forums, it looks like it will sell for $149 USD. Outernet have said that they are sending us a review sample, so keep an eye out for the review in the coming weeks.

The Outernet Dreamcatcher: RTL-SDR + LNA + Filter + Computing Hardware on a single PCB.
The Outernet Dreamcatcher: RTL-SDR + LNA + Filter + Computing Hardware on a single PCB.
Tweet23
Share
Reddit
Vote
Email
23 Shares

Some Tests on the LNA4ALL

Over on the SWLing post blog Tony Roper has uploaded his review and testing of the LNA4ALL. The LNA4ALL is a PSA-5043+ LNA produced by Adam 9A4QV in Croatia. It is normally considered as one of the best wideband LNAs for RTL-SDR users as it designed well, built well, runs well and is reasonably priced at 20 Euros.

On his post Tony tests the LNA4ALL and compares his measured gain specs against the claimed gain specs on the LNA4ALL website. At 5V power supply he found that the real vs claimed gains matched quite nicely.

Although the LNA4ALL is only specified to run down to 3.3V, Tony found that he could still get usable performance out of it with only a 1.2V supply. However, the gain was reduced by a few dB’s, and we also assume that the IP3 characteristics would also be sufficiently degraded at the low voltage.

Testing the LNA4ALL with his NASA Engine AIS receiver, he found that the LNA4ALL boosted his reception range from 15nm without the LNA, to 22nm with the LNA, and also tripled his received messages.

Tony's LNA4ALL Gain Comparions
Tony’s LNA4ALL Gain Comparions
Tweet
Share
Reddit
Vote
Email

Some HackRF Portapack Demos

The PortaPack is an addon created by Jared Boone for the HackRF software defined radio. It costs $200 USD at the sharebrained store and together with a USB battery pack it allows you to go completely portable with your HackRF. The HackRF is a multi-purpose SDR which can both receive and transmit anything (as long as you program it in) from 1 MHz to 6 GHz. 

Since we last posted about the PortaPack many new features have been added, and the firmware has matured significantly. Now the official PortaPack firmware allows you to receive and demodulate SSB, AM, NFM, WFM and display up to an 18 MHz wide waterfall. You can also decode marine AIS, the automobile tyre pressure monitoring system (TPMS) and utility ITRON ERT meters.

There is also a popular fork of the official PortaPack firmware called portapack-havoc, which is created by a dev who goes by the handle ‘furrtek’. This firmware is a bit more risky in terms of the trouble it can get you into as it enables several new features including:

  • Close call – See if anyone is transmitting near to you
  • A CW generator
  • a GPS and various other jammers
  • an LCR transmitter – the wireless protocol used in France for programming traffic related signage
  • a microphone transmitter
  • a pocsag receiver and transmitter – receive and send to pagers
  • a PWM RSSI output – useful for crude automatic direction finding
  • an RDS transmitter – transmit radio station text data to compatible broadcast FM radios
  • a soundboard – play a stored bank of wav sounds on a frequency
  • an SSTV tranmitter – transmit slow scan TV signals
  • an OOK transmitter – control on-off-keying devices such as doorbells.

Below we’ve created a YouTube playlist showing several videos that show the portapack in action.

PortaPack H1 Firmware 20160222

And below we show a tweet from @furrtek showing off the recently added SSTV transmit feature, and a tweet from @giorgiofox showing off the microphone transmit feature.

Tweet
Share
Reddit
Vote
Email