In his latest video Matt from the TechMinds YouTube channel shows us how to build a home made turnstile antenna for receiving the MILSAT SATCOM satellites where radio pirates from Brazil and other countries can often be heard.
The build involves 3D printed parts, metal measuring tape for the elements, some aluminum tubes and a coax phasing harness. After testing the VSWR with a meter, Matt tests the antenna with a handheld and finds it to be working well. He also later tests it with his SDRplay RSPdx and finds that the Turnstile outperforms his roof mounted vertical.
Back in March of this year we posted about an OpenWebRX fork called OpenWebRX+, which adds multiple built-in and ready to use decoders such as SSTV, AIS, CW and RTTY. OpenWebRX+ is a fork of the OpenWebRX project which is now officially maintained by DD5JFK.
Since our last post OpenWebRX+ has progressed in development further, and now includes a HFDL decoder via dumphfdl, various ISM band equipment decoders via rtl_433, FLEX pager decoding via multimon-ng, and a SELCALL decoder has also been added. Many other improvements and changes to the software have also been added, and the full changelog can be viewed here.
OpenWebRX+ is software for Linux. If you want to install OpenWebRX+, an easy path is to use the ready to use Raspberry Pi 4 image available on the releases page, or to use their PPA.
SSTV Image received by the luarvique fork of OpenWebRX. Credit: Neil Howard
GreenCube is a CubeSat by the Sapienza University of Rome, and it is designed to demonstrate an autonomous biological laboratory for cultivating plants onboard a CubeSat.
While this is an interesting mission in itself, for amateur radio operators there is another interesting facet to the satellite. Unlike most CubeSats which are launched in Low Earth Orbit (LEO), GreenCube was launched higher in Medium Earth Orbit (MEO) which provides a larger radio reception footprint over the earth. The satellite also contains a digital repeater (digipeater) at 435.310 MHz, which allows amateur radio operators to transmit digital radio packets up, and have the satellite repeat the packet back over a wide area footprint on earth.
Over on his latest video, Matt, from the TechMinds YouTube channel shows us how to receive and decode the packets from the GreenCube digipeater. In his demonstration Matt uses an SDRPlay RSPdx as the receiver, SDR++ as the receiver software, SoundModem as the packet decoder, GreenCube Terminal for displaying the messages, and GPredict for tracking the satellite and compensating for the doppler effect. He also notes that while a directional antenna on a motorized tracker is recommended, he was able to still receive packets with his omnidirectional terrestrial antennas without much issue.
Over on our store we've just reduced the price of the remaining stock of our RSP1A metal enclosure upgrade set. The price reduction brings it down to US$29.95 including free shipping to most countries.
This is a premium aluminum metal upgrade enclosure for the SDRplay RSP1A. It helps block RF interference and protects the RSP inside the sturdy enclosure. This is most likely to be our last production of this enclosure at least for a long period of time.
The kit includes 1x black aluminum metal enclosure with two labelled side panels, 1x black semi-hardshell carry case, 1x thermal pad to keep the RSP1A cool and mechanically stable inside the enclosure, 1x accessory set including enclosure screws, GND lug bolt set and 3M anti-slip rubber feet.
Please note that the set does NOT include the RSP1A.
The sale will only be available while stocks last. There are less than 50 units available from our international platforms, and less than 130 available at Amazon USA. So get in quick before they are all sold!
OpenWebRX is an open source web based SDR receiver program that allows you or others (if you allow them to), to access your SDR over the internet. It is compatible with KiwiSDR, RTL-SDR, Airspy, SDRPlay and many other software defined radio hardware. It was originally developed by Andras Retzler, but since abandoned by him, with a semi-official fork being maintained at openwebrx.de. However, other forks like luarvique can exist that implement a new set of features.
The full set of additions and improvements reads as follows:
This is the package repository for the improved version of the OpenWebRX online SDR. The new and original features available in this version of OpenWebRX:
Built-in SSTV decoder with background decoding.
Built-in AIS decoder.
Built-in CW decoder.
Built-in RTTY decoder.
Built-in MP3 recorder for received audio.
Image browser for received SSTV images.
Adjustable noise filtering based on spectral subtraction.
Adjustable tuning step.
Improved touch screen operation, with panning and zooming.
Improved scroll wheel support, with tuning and zooming.
Improved tuning in CW mode.
Bandpass filter adjustable with scroll wheel.
More reliable SDRPlay devices operation.
Better map information, with distances.
Better APRS map information, with weather.
Configurable session timeout, with a policy page.
HTTPS protocol support (requires SSL certificate).
The code comes packaged for Ubuntu 22.04 (amd64, arm64) and Debian 11 (amd64 arm64, armhf). There is also a ready to use Pi 4 SD card image available, linked on the GitHub readme. The original forked code can be found at https://github.com/luarvique/openwebrx.
According to discussion over on the OpenWebRX groups.io, the fork also runs on a Pi 3. In the image Neil Howard from the groups.io forum demonstrates an SSTV image he received with an SDRplay clone using the luarvique fork of OpenWebRX.
SSTV Image received by the luarvique fork of OpenWebRX. Credit: Neil Howard
Stefan also notes:
The maker of OpenWebRX+ Marek and also the maker of the original version of OpenWebRX Jakob are reachable via a Telegram channel: https://t.me/openwebrx_chat
We just wanted to note that after a few months delay due to a missing shipment carton which has just been found, the SDRplay RSP1A Enclosure Upgrade set is back in stock at Amazon for US customers. We also have stock available in our store and affiliated marketplace sites for non-US customers.
This is a premium aluminum metal upgrade enclosure for the SDRplay RSP1A. Helps block RF interference and protects the RSP inside the sturdy enclosure. We don't make batches of this enclosure often, and this batch could be the last if demand dwindles, so if you are interested please order before stock runs out for good.
The kit includes 1x black aluminum metal enclosure with two labelled side panels, 1x black semi-hardshell carry case, 1x thermal pad to keep the RSP1A cool and mechanically stable inside the enclosure, 1x accessory set including enclosure screws, GND lug bolt set and 3M anti-slip rubber feet.
Please note that the set does not include the RSP1A.
SDRplay have today announced a sale on their "RSPdx" product which runs from today until December 31st. The new pricing is £130/€156/$169.95 plus shipping and any applicable taxes. This pricing is available for direct sales from SDRplay, and at any participating resellers. The pricing on SDRplay's direct sales platform before the sale was US$214 plus shipping.
Note that individual resellers may be offering slightly different prices depending on if free shipping is offered. For example Ham Radio Outlet in the USA is offering the RSPdx for $179.95 including free shipping.
The RSPdx is designed for high performance DX reception and SDRplay note that it achieves this with additional filtering, improved intermodulation performance, a DAB notch filter, additional attenuation steps, and high dynamic range enhancements for frequencies under 2 MHz.
At SDRplay, we recognise that times are very tough for a lot of people. In view of the economic pressures that people are facing, we want to lend a helping hand by offering the very popular RSPdx at a special low price for this holiday buying season. After discussions with our dealer network, from Black Friday until the 31st December, we (along with participating dealers) plan to offer the RSPdx at a holiday discounted suggested retail price of £130/€156/$169.95 plus shipping and any applicable taxes. This represents a substantial discount of more than one fifth when compared to the normal retail price.
Starting midnight EST, Thursday November 24th visit https://www.sdrplay.com/purchasehome/ to purchase an RSPdx at the special price or contact your local SDRplay dealer for more details. Please also note that stocks are limited and this offer will certainly end on the 31st December and prices will revert to normal commercial levels thereafter.
This is a great opportunity to get the RSPdx as a gift for a newcomer or a returning radio enthusiast at a price which won’t be repeated, as our suppliers are already increasing their prices for the new year.
Prices shown are prices offered when buying direct from SDRplay. Shipping and taxes are extra. SDRplay ships from the UK to most countries in the world. However some countries will require import duty to be paid on top.
SDRplay dealers who usually include free shipping will adjust the prices accordingly
Check with your local dealer to see if they are participating.
Links to both the SDRplay direct purchasing page and our list of authorised resellers can be found here
Due to popular demand we have decided to manufacture one more batch of our SDRplay RSP1A metal enclosure upgrade kit. After numerous delays due to the Shanghai COVID lockdown, it is now in stock in our store and ready to ship out from our shipping warehouse in China. Amazon stock local to the USA will be arriving later around the end of July.
This is a premium aluminum metal upgrade enclosure for the SDRplay RSP1A. Helps block RF interference and protects the RSP inside the sturdy enclosure. We don't make batches of this enclosure often, and this batch could be the last, so if you are interested please order before stock runs out for good.
The kit includes 1x black aluminum metal enclosure with two labelled side panels, 1x black semi-hardshell carry case, 1x thermal pad to keep the RSP1A cool and mechanically stable inside the enclosure, 1x accessory set including enclosure screws, GND lug bolt set and 3M anti-slip rubber feet.
