From my Twitter feed: SDR rx, cool projects, JT-65

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Victor Laynez @roteno

July Call for Projects! Send links/pictures of your cool projects. One of mine: @eevblog uCurrent for my bench


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Bill WØSUN ? @w0sun

“JT65 – Easy as Pie!” #hamr #Hamradio

Software Defined Radio: new transceivers from Italy and India

Here are a few more links to SDR for amateur radio. I really gotta start building that SoftRock so that I can then tackle some of the more complex projects…..Dan

Click for full-size image.

Click for full-size image.

Elad FDM Duo SDR transceiver can be used with a computer or stand-alone. This little transceiver was demoed recently at the Ham Radio Fair in Friedricshafen, Germany. The Elad On-Line Shop does not yet list a price for this radio yet.

Apache Labs SDR rigs. These rigs are made in India and are commercial versions of the TAPR HPSDR designs. These radios are getting good reviews on eHam.

A $40 Software-Defined Radio. This article on SDR hacking from IEEE Spectrum mentions amateur radio.

From the trade magazines: litz wire, vector network analyzers, SDR

Another selection of amateur radio related items appearing recently in the electronic engineering trade publications.

Litz wire and other component cleverness
If you’re not familiar with it, litz wire is not named after a person or a place. It’s short for Litzendraht, the German term for braided, stranded, or woven wire. It’s a very clever solution to the problems and inefficiencies caused by the skin effect — as the frequency of the current that a wire carries increases, the current tends to go to the outside of the wire.

Vector network analyzers support versatile testing
Among the most valuable of RF/microwave test tools is the vector network analyzer (VNA), which can measure amplitude and phase with frequency. VNAs have long become associated with the measurements of complex impedance parameters—such as scattering (S) parameters—using the test data to design efficient impedance matching networks for the optimum transmission of high-frequency signals through active and passive devices and networks. At present, VNAs are available from both well-known and not-so-well-known instrument manufacturers, in both bench top and portable configurations for making measurements on high-frequency (HF) through millimeter-wave-frequency signals.

Integrated RF analog, multi-standard, software-defined radio receivers
The scaling of CMOS technologies typically has a great impact on analog design. The most severe consequence is the reduction of the voltage supply. Imec and Renesas have managed to put a complete, high-performance SDR (Software Defined Radio) receiver into a 28nm CMOS process with a 0.9V power supply. The IC has everything except a PLL on a single monolithic chip. (See Figure 1.) This is an impressive integration of analog functionality.

From my Twitter feed: SDR, Hallicrafters, digital voice

Just found this resource: Coverage down to 50mHz is possible with one type & down to 22mHz with another.

Wish I had the time to play with these things…..Dan

W7DTG: Another boatanchor receiver demonstration Hallicra…


Amateur Radio – FreeDV – Digital Voice Software for Amateur Radio #hamradio #hamr #dx#swl

I’m still not sold on digital voice, but if it were easy to set up, like say PSK-31, I’d give it a try, at least….Dan<

Ads of Note from the December 2012 QST

When I was a kid, I used to religiously pore over the ads in the Electronics Illustrated, Popular Electronics, and later on, QST issues that I received. I don’t do that every month nowadays, but I think it is a worthwhile exercise to do every two-three months. New products are always being introduced, and some of them can be quite useful and fun.

This month, I went through the ads in QST. Here are some that I highlighted.

  • Using Your Meter. This is a new book from The W5YI Group. It’s notable to me because I’ve been thinking that a simliar book might be my next publication. The No-Nonsense Guide to Using Your DMM—my working title—would be a lot cheaper than the $24.95 that W5YI is asking for this book, though.

    Got any tips for using a DMM? If so, e-mail me and I’ll include it in the book.

  • Bonito RadioJet 1102S. This is a software-defined receiver made in Germany and imported by a small company, Computer International, in Michigan. Unfortunately, the company’s website is a real disaster. I spent about ten minutes looking for a price for this radio without any luck.  So many small companies’ websites are so poor that I think it actually hurts, rather than helps their business.
  • MastrAnt. This company sells synthetic guy ropes. We’re going to need some of this down at the museum. I think the metal guy wires are detuning our 40m inverted Vee.

Do you peruse the ads in QST and other ham radio magazines? Which ones have you found interesting lately?

On the Internet: $100 supercomputer, 13 yo reviews his HT, HackRF covers 100 MHz – 6 GHz

Here are  a couple more interesting tidbits gleaned from the Internet over the past week or so:

  • Personal supercomputer for only $100! This blog post describes reports on a company called Adapteva, which sounds like it’s still basically a basement operation, that’s developed a low-power, high-Gflops processor chip. Their current project is to develop a very low-cost supercomputer using this chip. One of the possible applications they’re targeting is software-defined radio.
  • 13-year-old reviews the Quansheng dual-band HT. A new ham reviews his dual-band HT. Bottom line: he likes it!
  • HackSDR to rule the airwavesHackRF is a software-defined radio (SDR) that will potentially receive and transmit any radio frequency from 100 MHz to 6 GHz. HackRF is intended to hit the sweet spot between versatility and cost – around the size of a USB hard drive and with a $300 price tag,

From the trade magazines – 7/25/12

Here are a couple of items from the electronics engineering trad magazines that hams might find interesting:

Digital and analog PC TV dongles—the basics. Some amateur radio operators are using these dongles as a software-defined radio (SDR).

Can public-safety radio’s P25 survive LTE? P25 has been with us since 1988, but its capacity and bandwidth are being obsoleted by the latest and anticipated next generations of cellular technology.

Material effectively replaces gold. Impact Coatings claims that its Silver MaxPhase performs like gold while carrying a much lower price tag.

TAPR accepting Hermes orders

From the tapr-announce mailing list:

TAPR is pleased to announce that Hermes, an HF transceiver incorporating the capabilities of the existing “Atlas Bus” HPSDR receiver, exciter, and computer interface onto a single board, is now available for order at

The Hermes board is completely assembled and tested, and is offered at the following prices.

TAPR member: $895
TAPR non-member: $940

The order page will close Wednesday July 25th, so don’t delay!

Please note that TAPR will be building only one production run of Hermes boards, and will only build the number necessary to fulfill the orders received on or before before the July 25th cutoff date.

Estimated delivery is October 15, and earlier if possible. Be a part of history and support HPSDR!

More information here:

Order here:

Software-defined radio is one of those things that I just really haven’t gotten into yet, and I feel like I’m getting further and further behind. How about you? Should I really care?

Winter 2012 TAPR Journal now online

The TAPR PSR Digital Journal, Winter 2012 edition, is now online ( Contents include:

  • President’s Corner
  • iQuadLabs-TAPR Agreement
  • 2011 DCC Video Online
  • TAPR Directors Elections
  • VK5DGR on Codec 2 at 2012
  • Doodle Labs DL-435
  • Going to Ohio
  • When Digital Was Mechanical
  • Now on YouTube
  • TAPR-ARRL DCC 2011
  • HPSDR Projects
  • Frequency & Time Related Kits
  • The Great Create
  • My Steve Jobs Story
  • LW and MW DX
  • Join TAPR on Twitter & Facebook
  • Write Here!
  • PSR Advertising Rates
  • Still Fixing a Little TAPR History
  • The Fine Print
  • Our Membership App

TAPR starts “interest list” for Hermes SDR

From the TAPRARRL Letter, 3/22/12:

Tucson Amateur Packet Radio (TAPR) announces the opening of the “interest list” for the openHPSDR Hermes single-board Software Defined Radio. The Hermes interest list is used by TAPR to determine the number of Hermes boards to manufacture in the pending initial production run this spring. Hermes is a long-awaited addition to the openHPSDR project lineup, advancing through four prototypes while evolving from a USB-based to an Ethernet-based transceiver in about two years. Hermes is a Direct-Down-Conversion receiver, a Direct-Up-Conversion 500 mW transmitter and a gigabit Ethernet interface all on one board. Also on board is an RF-quiet switch-mode power supply, which allows Hermes to run from a single 13.8 V dc source. Read more here.