Archive for category Shortwave Listening

Kenwood and Yaesu, where are you?

ICOM’s IC-7300, r8500, IC-7610 and the currently upcoming IC-9700 are making huge impacts on AROs everywhere. This is no surprise to those of us familiar with SDR technology; older analog methods simply cannot offer the kinds of performance advantages a good SDR design can.

However, one thing these radios from ICOM have in common are some poor design choices; spectrum span choices are crippled compared to a center/demodulator tuning scheme; spectrums and waterfall displays that are insufficiently adjustable; noise blankers in the least useful portion of the signal path; insufficient “knobbiness”, so that the user interface of the radio is a great deal more clumsy than it actually needs to be.

The opportunity for Kenwood and Yaesu is clear: there’s an opening here to step in and knock ICOM off the hill they climbed up on.

Imagine a stand-alone SDR transceiver where:

  • You could conveniently place the spectrum/waterfall anywhere
  • You could adjust the amplitude/level of the waterfall and spectrum separately
  • The noise blanker reduced the noise on the display as well as in the audio
  • The display was capable of high resolution output to a monitor
  • Transmit pre-distortion provided very high quality TX
  • Important controls were given their own front panel placement
  • Full mouse/trackball integration was standard
  • Broadband IQ output was available for external use
  • Multiband EQ and compression / limiting for TX audio was provided

These are just some of the obvious places where ICOM’s radios, thus far, have fallen woefully short.

Yaesu? Kenwood? Where art thou?

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New SW station in West Australia up and testing

A new SW station is presently running test transmissions between 11:00 – 14:00 UTC. The transmitter is located near Perth, Western Australia, on 5,045 kHz, and is running 75 watts (300 PEP.) You can send listener reports to

At present, the station is ghosting the audio from sister station, so you can use that to confirm what you’re hearing.

It’ll likely be a tough catch here in the USA, but that’s the fun of it!

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An Interesting AM BCB DXer’s catch

KVCK, at 1450 AM, broadcasts a monophonic signal using the standard monophonic AM modulation scheme. The music feed to the station from its content provider, however, is stereo, and KVCK routes only one channel of that feed to its transmitter. So for any content that provides fully panned mix to the missing channel, no sound reaches the listener.

This problem has existed for decades, the station has been notified many times about it by email and in writing, yet it persists. The solution should be as simple as a stereo-to-mono cable or mixer, or, if the content is provided digitally, by a software setting or a call to the content provider.

That this has never been corrected comprises an interesting mystery with regard to KVCK, and makes it an unusual DX catch for BCB DXers.

Here’s a 20-second fragment of Marvin Gaye’s "Heard it Through the Grapevine"

First, here’s how it should sound. Pay attention to the ladies in the chorus from 13s to 20s:

Full mono, both tracks combined properly

Now, here it is from KCVK, on the afternoon of September 28th, 2016… listen again at 13s to 20s:

One track only (incorrect mixing at station or content provider.)

KVCK is like one of those double-struck pennies from the US mint. Very rare, and not a very good product — but interesting!

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GAP 20m Monogap Vertical Dipole Review

I’ve been setting up a small trailer for use as a mobile, independently powered radio station for use at HF and VHF. To that end, it has its own deployable solar panels, internal power storage, and dedicated power conversion electronics. There are quite a few 12.6 VDC VHF and HF radios out there, and I own several, so the radios are less of a problem than a situation where I have to make some kind of fun decision between multiple good options.

VHF antennas are no problem. But the HF antenna… There’s the rub. If it’s to be truly portable, that means it cannot be large, and it will not be high in the air. Those are very significant drawbacks for most antenna systems; they directly impact both receive and transmit performance. So I went hunting. Eventually, I happened upon the Monogap 20 meter antenna, which is a vertical dipole; easily portable within the frame of reference of what can be safely transported in the bed of my pickup, light, easily mounted and unmounted, inexpensive, and — as it turns out — a surprisingly good performer.
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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.
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SdrDx 2.16a for OS X and Windows

Here we go:
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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.
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SdrDx 2.14o for Windows and OS X Available

The 2.14o version of SdrDx for OS X ** and ** Windows is
now available and the online documentation has been updated
to reflect the changes that have been made.

SdrDx is free; it supports RFSPACE SDRs, both FunCubes,
the Andrus MK 1.5, and the AFEDRI.

The SoftRock/Peabody SDRs will also work, but it takes
some technical knowledge of scripting to make that happen.
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