Category Archives: Software Defined Radio

mySdrPlayback: new version adds a DGPS decoder

mySdrRecordingWaterfall

Many thanks to Chris Smolinski, at Black Cat Systems, who recently announced new mySdrPlayback features:

I’ve released a new beta of mySdrPlayback, which is a Mac app that lets you easily go through SDR recording files. It works with recording files produced by SdrDx and SpectraVue, as well as Perseus.

This version adds a DGPS decoder that decodes from every DGPS channel in parallel, looking for messages. Makes it super easy to DX DGPS stations, just record overnight, then run the recordings through the app in the morning, and you get a list of all of the decoded messages from the various stations.

Click here to view the information and download page at Black Cat Systems.

Brazilian DX heard in Oxford UK, with venerable Sony ICF-2001D

Hi there, I thought I would share some Brazilian shortwave catches with you, obtained using my Sony ICF-2001D receiver and 200 metre experimental longwire. The first is Radio Bandeirantes, Sao Paolo on 9645.4 kHz. This is a station that I’ve only heard once or twice previously, but was received with excellent signal clarity and strength recently, using my deployable longwire antenna. I would rate this station as moderately difficult to receive with reasonable discernibility. The second is Radio Novo Tempo from Campo Grande, on 4894.9 kHz. This station I would rate as difficult to hear with discernible audio. The key is always signal-to-noise, thus moving yourself out of the ubiquitous blanket of QRM most modern environments endure will usually achieve this and of course coupled with sufficient space outdoors to erect a larger antenna will hopefully also improve signal strength. My final video on this post is Radio Nacional Brazilia on 6180 kHz. I would regard this station as quite easy to hear well; their effective TX power towards Europe is around 2 MW, however, outdoors, this station can literally boom in, with what might be perceived as local-AM signal strength. I hope you enjoy watching the videos and seeing/ hearing what’s possible with a modest set-up. As for the Sony ICF-2001D? Well the design is more than 30 years old, but in my opinion at least, still one of the very best portable shortwave receivers ever manufactured. Thanks and 73.

 

Direct link to Oxford Shortwave Log for reception video of Radio Bandeirantes

 

Direct link to Oxford Shortwave Log for reception video of Radio Novo Tempo

 

Direct link to Oxford Shortwave Log for reception video of Radio Nacional Brazilia

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Radio Fana 6110 kHz Ethiopia; excellent SNR with Elad FDM DUO

FanazaThe Elad FDM DUO makes for a fantastic receiver, in both standalone mode and via the FDM-SW2 software. Thus far it has been demonstrating this by outperforming the Sony ICF-2001D in many of my reception tests using an experimental longwire antenna. Bear in mind that whilst this might not be such a surprise, the Elad without the FDM-SW2 software driving it has no SYNC, which is often invaluable for Tropical Band DXing. To make the point further, here is a wonderfully clear signal from Ethiopia, with, in my experience at least, exceptional signal-to-noise.

My 200 metre longwire is still very much a work in progress. I am in the process of building a termination resistance box, receiver-end termination suitable for high and low impedance inputs and earthing straps for metre-long copper pipes that will remain in-situ. When I have completed these tasks, I will record a video because I know some of you are interested in the details. For now though, it just remains an experiment – 200 metres of wire and very late nights/ early mornings!  Recorded at the ‘DX woods’ in Oxford UK at 03:23 hrs UTC on 31/07/16. Thanks for watching.

Direct link to Radio Fana reception on the Oxford Shortwave Log YouTube channel

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

 

Creating a global network of inexpensive remote SDRs

U_Twente_SDR

Many thanks to SWLing Post contributor, Mark Fahey, who replies to Ivan’s preliminary review of the V3 RTL-SDR dongle:

With Shortwave SDRs (the receiver dongle) now costing less than $20, the time has come for us to set up a global group of receivers that we can all log into at will!

RTL-SDR-RTL2832U-e1471375714199Have a look at SDR.hu – here you can put your SDR dongle on line and share it with anyone and they have full control of the receiver just as if it was in their own shack.

Imagine receivers scatted around the world – South America, Tropical Asia, Africa! The cost is now virtually nothing, all that is needed is the dongle, antenna (doesn’t have to be anything special – even a long wire or whip) and a small low cost CPU (Raspberry Pi for example).

Anyone else interested in this dream? Lets get together, get some receivers setup and then talk about our experience in a kick-ass presentation at the 2017 SWL WinterFest in PA!

Also… I am very soon to receive my KiwiSDR matched to a BeagleBone CPU. It will be online at SDR.hu and four remote listeners will be able to tune the full shortwave bands independently, its like my own Twente setup! Heaps of others are getting receivers online in the next few months with KiwiSDRs, this is going to be totally amazing!

I agree, Mark! While there is already quite a network of remote SDRs and receivers in the world, the barrier of entry keeps getting lower and lower. It’s hard to imagine that $25 can buy an SDR that natively covers the shortwave and mediumwave bands!

There’s only one other requirement for an online SDR that Mark didn’t mention: a decent Internet connection. Sadly, this is the only thing keeping me from hosting a remote SDR here at my home. I considered purchasing a KiwiSDR like Mark, but my upload speed (0.2-0.3 mbps) is so terrible and so unreliable that I could only host one listener at a time at best. You can bet that as soon as my ISP upgrades our service, I’ll launch a web SDR as well.

Of course, I’m willing to bet that most SWLing Post readers have more than enough bandwidth to host a $25 remote receiver! Let’s make Mark’s vision a reality!

Ivan’s preliminary review of the new RTL-SDR dongle on shortwave/mediumwave

RTL-SDR-RTL2832U-e1471375714199Many thanks to SWLing Post contributor, Ivan Cholakov (NO2CW), who shares the following video review of the new RTL-SDR dongle on the shortwave and mediumwave bands.

Ivan notes:

This is daytime reception comparison. Nighttime could be a different picture. [The RTL-SDR dongle] tunes and frequency is 100% on spot.

Using SDR Sharp you have several AGC settings to play with and find the best combination. The best setting seems to vary with band and signal strength.

The [SDR receiver] comes with a short (20 cm) and long (120cm) telescopic antennas. Neither one is usable for HF or Medium wave.

When ordering the radio you have to get a USB extension cord for the dongle. When plugged in directly into a laptop and then antenna coax it can become bulky. You also will most likely need an SMA adapter to BNC and SO 238.

I hope this helps.

Click here to view on YouTube.

Many thanks for sharing your video, Ivan! For a $25 SDR, I’m pretty impressed so far! I’m also very curious how it will hold up to stronger nighttime signals and, especially, adjacent signal interference. I imagine it may be prone to overloading as well. Please keep us posted!

Have any other Post readers tested the new RTL-SDR dongle on HF? If so, please comment!