Posts Tagged radio

What is a Voicelid?

On the ham radio bands, a voicelid is an operator who is transmitting voice within, or partially within, a portion of the band traditionally reserved for data.

For instance, the USB carrier frequencies 14.230 MHz and 14.233 MHz have traditionally been reserved for slow scan television operations (also known as “SSTV”) for more than 50 years now:

20 Meter ARO Band

20 Meter ARO Band

So with regard to these frequencies, USB voice operation above 14.227 MHz (presuming 3 KHz voice bandwidth, which is generous) and below 14.236 MHz self-identifies the operator as a voicelid, as would (non-traditional, to say the least) LSB carrier point operation below 14.239 MHZ and above 14.230 MHz.

This is true both during non-contest and contest periods. Contests provide no legitimate excuse to intentionally interfere with others — that’s not radiosport. That’s simply rude, as well as outright forbidden.

This does not apply to USB voice transmissions on 14.230 or 14.233 that are actually SSTV related — those are part of normal SSTV operations.

So take a little time to learn about traditional non-voice allocations on all of the bands you operate within, and carefully respect the tiny bits of bandwidth they occupy. This is one of those important bits of operational knowledge that distinguishes the skilled radio operators from the unskilled ones.

#voicelid #sstv

Tags: , , , , , , , ,

ICOM IC 7300 Transceiver Review




ICOM IC 7300 marks an important inflection point for the “big three” amateur radio manufacturers: The beginning of true software-defined RF processing from one end to the other.

As the first full SDR transceiver from “the big guys”, it is interesting to consider the price point, feature set, and performance both in light of the legacy analog designs, and as compared to what SDRs are known to be capable of.
Read the rest of this entry »

Tags: , , , , , , , , , ,

Amateur Radio Callsign utility

Screen shot 2015-05-02 at 11.36.46 AMWhen creating reports involving amateur radio callsigns, it is useful to be able to sort them according to region, prefix and postfix, as this is the way we are accustomed to thinking about them. In addition, padding them so that call regions align and other types of worthy formatting are applied is something I have found to be very handy.

For this purpose, I developed, a Python import library. You are welcome to use it.

Click here to download the zipped library.
Read the rest of this entry »

Tags: , , , , , , , , , , , , , , ,

Review: E-Flite Blade 350 QX Quadcopter

The Blade 350 QX quadcopter is an almost-perfect example of its class. Three flight modes provide almost the perfect range from well behaved and safe to crazily agreeable to any insane set of control inputs you supply.

Blade 350 QX

Blade 350 QX

It is light, provides a reasonable flight time with the supplied battery, and you’re pretty well guaranteed to have more fun than you expect fooling around with it.

But that’s not all. The 350 is powerful enough, and stable enough, to carry a Go Pro camera and take awesome HD movies and stills from the air. You can spin the quadcopter in place and create a fabulous pan, or fly right up to something you otherwise can’t get to and take a closeup. Or just fly around and take a look at the countryside.

Everything you need is supplied in the package; the quadcopter, the hand controller, batteries, a charger (12 vdc… meant to hook to your car’s electrical system so you can recharge in the field), and you even get a set of extra blades. Which you are unlikely to need if you are even just a little bit careful. The manual is a little dense, and because of that you’ll have to read it carefully, but everything you need to know is actually in there within twelve pages.
Read the rest of this entry »

Tags: , , , , , , , , , , , , ,

New OSX and Windows version of SdrDx – 2.11

SdrDx 2.11 adds visible memory markers, an enhanced internal database, better panning window width by window width, a number of fixes and performance improvements, and additional documentation.

  Screen shot:

Tags: , , , , , , , , , ,

New version of SdrDx – 1.10

Please see this post for the latest details on v1.10.

Tags: , , , , , , , ,

SWLs: WLO RTTY news feed on 8473 KHz

So there I am, minding my own business at 2am or so my time, tuning across 8 MHz with SdrDx using my 20 meter inverted vee, and I see a RTTY signal. Ever the optimist, I fire up the Jack server (this connects the audio output of one application on the Mac to the input of another application), then an old version of fldigi I have lying around, “jack” them together, and lo and behold, the signal is unencrypted, 45 baud 170 Hz shift RTTY. That was startling enough, but the signal turns out to be a news feed, something I haven’t seen on the shortwave bands in at least ten, perhaps as much as twenty, years.
Read the rest of this entry »

Tags: , , , , , ,

SdrDx –OS X and Windows SDR Software

I’ve been working on developing OSX/Mac and Windows versions of SdrDx. At this time, SdrDx for OS X and Windows supports Ethernet-connected version of AFEDRI SDRs, the USB-connected Airspy (AirSpy HF+ under OS X only, via this OS X server), Ethernet-based Andrus MK1.5, USB FunCube Pro, USB FunCube Pro Plus, Peaberry, Ethernet based RFSPACE SDrs, USB RTL sticks (RTL supported under OS X only, via this OS X server) and Softrock SDR receivers. Both the Peaberry and Softrock SDRs require a lot of expertise to get working. The others are pretty much plug-and-play.

SdrDx 2.17a

SdrDx 2.19n

In addition, SdrDx can be made to support any SDR with a sound card interface, including I/Q input via your native or auxiliary sound card, with a little scripting work; the Peaberry and Softrock support use this mechanism via Python.

SdrDx (running on the Mac) is shown to the right. SdrDx is a closed-source, free application.

SdrDx, in combination with your SDR, is an extremely powerful receiver. Reception, recording, playback, analysis, processing — it’s all there, and it’s all been made as easy to use as possible. Extensive documentation covers every aspect of operating the software, as well as providing numerous examples and images to help you along. If you’re an expert radio user, you’re sure to settle right in. If you’re still learning, you can look forward to software that lets your capabilities grow with your knowledge.
Read the rest of this entry »

Tags: , , , , , , , ,