Archive for category Amateur 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

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Kenwood and Yaesu, where are you?

ICOM’s R-8500, IC-7300, IC-7610 and IC-9700 are making huge impacts on AROs everywhere. This is no surprise to those of us familiar with SDR technology; older analog radio designs 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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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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