Category Archives: Software Defined Radio

Video: DL1DN’s amazing QRP DX and being aware of uSDR clones

Many thanks to Steve (MW0SAW) who shares the following video of DL1DN making a very enthusiastic contact with VK5MAZ–Germany to Australia–QRP SSB pedestrian mobile:

What an amazing accomplishment! I think I felt as excited as David did in his video. The reception of VK5MAZ was simply phenomenal, too!

uSDR clones

David (DL1DN) mentions at the end of his video that he had been in touch with Manuel (DL2MAN) who is the designer of the incredibly affordable uSDR transceiver project. David had featured a Chinese clone version of the uSDR in some of his previous videos. These days, it’s difficult to know if you’re ordering a clone or the original item because often the clone so closely mimics the original.

As I understand it, the uSDR is completely open source and, at least at time of posting, there is no comprehensive kit version available. However, all of the information needed for gathering parts and building the uSDR are public and free.

Manuel (DL2MAN) made the uSDR project open source with the condition that it cannot be used for commercial purposes (in other words, produced by another party and sold as a product). Of course, it was very quickly cloned by manufacturers in China and is now available on eBay.

David shared a link to Manuel’s recent video speaking about the differences between the two units:

You’ll note that I try to steer clear of clones on QRPer.com. I do this mainly because I like supporting the original developers and designers of radios and kits when possible. I feel like by doing this, I’m supporting the innovators in our community as opposed to taking money away from them.

On that note, I’m in the market for an M0NKA mcHF transceiver!

The Microsoft Surface Go: My portable logging computer

I’ve received numerous questions from readers and viewers about the computer I use for logging POTA contacts in the field and realize that I have neglected to highlight it even though it’s an integral part of my field kit when space allows.

The Microsoft Surface Go

The Surface Go  is essentially a touch-screen Windows 10 tablet with a magnetically-attached keyboard (typically sold separately). It has a fold-out back stand and when the keyboard cover is closed, it stores flat (and is incredibly thin).

In short: I absolutely love the Surface Go and it is an example of the one time when an impulse purchase actually paid off!

In 2019, on the way back from the Huntsville Hamfest, I stopped by the Unclaimed Baggage Center in Scottsboro, Alabama. This center has a wide variety of used portable electronics at discount prices. I felt pretty lucky when I discovered a like-new condition Microsoft Surface Go tablet and keyboard with original charger for $190.

The catch? This unit (like all of their units) was used, had no documented user history, and I had no idea if it would be noisy (in terms of RFI/QRM) when paired with or near my radios.

Another issue was that the only data port on the tablet is a USB-C. But I grabbed a small USB-C to standard USB 3.0 dongle (for $2!) and took a risk that it would work with my portable SDR receivers and transceivers. In short: it did.

One huge bonus? The Surface Go has a dedicated power port. So many other tablet options do not as they’ll use their one data port for both power and data.

I immediately ordered a DC power cable with a standard car lighter plug. In the field, I can hook the Surface Go up to my LiFePo4 battery and power it for ages. Even a modest solar panel will also charge it in short order.

The Surface Go paired with my Airspy HF+ Discover SDR and a homebrew noise-cancelling passive loop antenna. A portable hotel DXing setup!

While this Surface Go is no CPU powerhouse (I’m guessing mine is a first generation–there are faster generations available) it’s fast enough to run my logging software–N3FJP’s Amateur Contact Log–and to even make spectrum recordings with my SDRs up to 2 MHz in bandwidth without stuttering.

The only noise it seems to inject into the mix is a little RFI when I touch the trackpad on the attached keyboard and this is typically only centered around the 20 meter band. That can often be solved by simply moving the tablet further away from the radio or using the touch screen rather than the trackpad.

The Surface Go has ample horsepower to run applications like WSJT-X flawlessly and, as I mentioned, I’ve even made numerous spectrum recordings which is much more demanding on CPU resources. Indeed, I even wrote a piece about portable SDR DXing with the Surface Go for The Spectrum Monitor magazine–click here to read the full article on the SWLing Post.

I recently paired the Surface Go with my IC-705 and made FT8 contacts confirming that it’ll make for a simple digital mode setup in the field.

I love the Surface Go and will plan to purchase another when this one eventually dies. I’ve found it much more useful than my iPad, Android tablet, or even a full sized laptop. When I’m back to doing ultralight one-bag air travel, the Surface Go will be my travel PC as well.

Where to buy?

Of course, you can find the latest releases of Surface Go at retailers like Amazon.com (affiliate link), or any big box electronics retailer.

If you’re willing to take your chances on a used one, like me, you might check out eBay.com or better yet, Swappa.

Of course, if you can make a detour to Scottsboro, Alabama, check out the Unclaimed Baggage Center!

Initial impressions of the ALT-512 QRP transceiver

(Note: This is a cross-post from my other radio blog, the SWLing Post.)

So the ALT-512 QRP SDR transceiver has landed at SWLing Post HQ. This little rig is on loan from Aerial-51 and I’ll be spending the next month or so putting it through the paces.

I can already tell that the ALT-512 has some strong points:

  • It’s incredibly portable and easy to take to the field, providing you have a battery and resonant antenna (or external ATU).
  • The color backlit display is quite readable at any angle despite being rather information-dense.
  • I really like the waterfall display. It’s large enough to be quite useful.
  • The ALT-512 can connect directly to your computer for digital modes like FT-8. No external sound card needed.
  • The menu system contains a wide array of features and options for granular tweaks and modifications.
  • The ALT-512 includes the European 4 meter band.
  • Although I prefer using headphones with small radios, the ALT-512’s small internal speaker does a fine job.
  • Rob Sherwood tested the ALT-512 (indeed, this very unit) recently and added it to his receiver test data. It performed quite well especially considering the price.

Any negatives so far?  Nothing major:

  • No internal ATU or battery options. At this price point (799 EUR), I wouldn’t expect either of these.
  • The ALT-512 is not general coverage. This is a negative for those of us who like SWLing, but a positive for ham radio use as the ALT-512 sports band-specific bandpass filters to reject out-of-band strong stations. You can tune to some stations above the 40M band and also the full mediumwave band and below (down to 100 kHz), although I wouldn’t expect stellar performance in those regions.

So far, I’m very pleased with the ALT-512’s performance.

Next, I’ll be taking it to the field and see how easily I can activate a few POTA (Parks On The Air) sites! Stay tuned!

Click here to check out the ALT-512 at Aerial-51.

Icom Introduces the IC-705 portable QRP transceiver

Note: this is a cross-post from our other radio blog, the SWLing Post.

This weekend at Tokyo’s Ham Fair 2019, Icom announced an innovative transceiver to their line-up: the Icom IC-705 QRP transceiver.

The IC-705 introduces several industry firsts for a backpack portable radio:

  • It uses the same BP-272 Li-ion Battery pack as the ID-51 and ID-31 series D-Star handy talkies. To my knowledge, this is the only HF transceiver that uses battery packs that can be swapped so easily in the field–like one would swap an HT battery pack
  • It has a general coverage receiver that spans a whopping 0.5 to 148 MHz
  • It sports a full color, touch screen with spectrum and waterfall displays
  • It includes the D-Star digital voice mode
  • A GPS receiver
  • Bluetooth connectivity
  • A MicroSD card slot for memory storage, screen captures and recordings

All of this appears to be included, not add-on options.

The only IC-705 omission, in my opinion, is an internal ATU (antenna tuner). Something I would have expected, but not a deal-breaker for those of us who could really benefit from the amount of features this radio offers.

Side and back panel view noting ports and connections.

There is no word yet on pricing or availability, but you can count on us to post these details once they’re available. If you would like to follow updates, bookmark the tag: IC-705

We will also review on the Icom IC-705 as soon as it’s available.

Video from Amateur Logic/Ham College

Ray Novak (N9JA) with Icom America did a live video interview with Amateur Logic/Ham College TV yesterday. The video includes a full announcement in English from the Icom Booth:

Click here to view on YouTube.

IC-705 Pre-Release brochure

Many thanks to Ray Novak for snapping a few photos of the pre-release brochure:

Update: click here to download the full IC-705 brochure. Hat tip to Dave Zantow!

A surprise from one of the “Big Three”

The “Big Three” transceiver manufactures–Icom, Yaesu and Kenwood–have not shown a lot of interest in backpackable QRP radios over the past two decades.

By “backpackable” I mean QRP transceivers specifically designed for portable use in the field–radios that typically have built-in battery options, internal ATUs, and designed to be lightweight shack-in-a-box units.

Yaesu introduced the FT-817 almost twenty years ago and it lives on today (with modest upgrades) as the FT-818. Kenwood has no portable/backpackable HF QRP radio at this point.

I bet the IC-705 is being introduced today because Icom sees a strong market among field-portable operators who enjoy travel and outdoor radio activities like SOTA (Summits On The Air) and POTA (Parks On The Air).  In addition, many ham radio operators live in neighborhoods that are either plagued with radio interference (RFI) or don’t allow antennas to be installed outdoors. Portable radios liberate ham radio ops from their shacks and allow them to set up a station far away from noise or home owner’s associations.

Looking forward…

Again, I’ll be in touch with Icom about the IC-705 and will share updates here when they’re available. I’m looking forward to evaluation this rig when it hits the market!


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Elecraft introduces the K4 high-performance direct-sampling SDR

The following is a cross-post from my other website, The SWLing Post:

Click to enlarge (Source: K4 Product Brochure)

Today we learned about the latest addition to the Elecraft product line, the Elecraft K4.

This fills a niche in the Elecraft product line and is certain to directly compete with the likes of the Icom IC-7610 and a number of Flex Radio transceivers, among others.

Elecraft describes the K4 as having a “modular hybrid architecture”. Below, I’ve pulled the text and images from the Elecraft product brochure.

Wayne Burdick (N6KR) of Elecraft notes that tomorrow (Friday, May 17, 2019) the Elecraft site will (re)launch a K4 product page with pre-order/reservation page.

I plan to learn more about the K4 and report back during Hamvention this week. Stay tuned by bookmarking the tag Elecraft K4:

Elecraft K4 Product Information

(Source: Elecraft K4 Product Information Sheet via Lutz Electronics, Switzerland)

Click to enlarge (Source: K4 Product Brochure)

A direct-sampling SDR you’ll love to use

Our new K4 harnesses the latest in signal processing while retaining the best
aspects of the K3S and P3. The resulting user interface makes the technology
transparent, allowing you to focus on working the world.

160-6 meter, all-mode coverage & dual RX

The K4 includes dual receive over 100 kHz to 54 MHz. Since it utilizes direct
sampling, there’s no need for crystal filters in the K4 or K4D (see Models, back
page). For extreme-signal environments, we offer a dual superhet module
(standard in the K4HD). An internal VHF/UHF module is also planned.

High-resolution mini-pan for each receiver

Our advanced fine-tuning aid, with its resampled bandwidth as narrow as +/- 1
kHz, is displayed separately from the main panadapter. You can turn it on by
tapping either receiver’s S-meter or by tapping on a signal of interest.

Simple operation and setup

The K4 features a large, full-color touch display, combined with a rich set of real
controls. Per-VFO transmit metering makes split mode completely foolproof.
Band-stacking switches and per-receiver controls are both intuitive and versatile,
adapting to operating context. Usage information on these and other features
is just one tap away, thanks to our built-in help system.

Click to enlarge (Source: K4 Product Brochure)

Rich I/O complement

The rear panel includes all the RF, analog and digital I/O you’ll need to complete
your station. All K-line accessories are supported, including amps, ATUs, and our
K-Pod station controller. The HDMI video output supports an external display
with its own user-specified format.

Full remote control from multiple devices

The K4 can be 100% remote controlled, via Ethernet, from a second K4 as well as
a PC, notebook, or tablet. Panadapter data is included on all remote displays.

Modular hybrid architecture

The K4 adapts to your needs, with three models to choose from:

  • Basic K4 with wide-range dual receive
  • K4D with diversity receive
  • K4HD with a dual superhet module for exceptional dynamic range

You can upgrade or add options as desired, or as new technology becomes
available. This extensibility applies to software as well. The K4’s powerful, fast-starting CPU provides unlimited expansion opportunities.

Fast signal processing

The RF signal chain in the K4 incorporates parallel hardware processing of data
streams, including a dedicated DSP subsystem. This, combined with silent,
PIN-diode T/R switching, ensures fast CW break-in. Data and speech-processing
delays are also minimized.
Standard DSP features include easy-to-adjust, per-mode RX/TX EQ; clean,
punchy RF speech processing; full DVR capabilities; and several built-in data
decode/encode modes. Direct-sampling technology results in an ultra-flat
passband response for clean RX and TX audio. Since the signal chain is softwaredefined, the DSP can be field upgraded to add new algorithms and operating
modes.

KAT4 ATU

The KAT4 ATU has a nominally 10:1 matching range. It includes 3 antenna jacks,
any one of which can be selected as an input for one or both receivers.

Internal VHF/UHF module (future option)

An expansion slot is reserved for a high-performance VHF/UHF module, with
output of approximately 15 W. This module will support all modes.

Kit version

A no-soldering kit version of the K4 is planned for later release. Builders will learn
about advanced radio technology as they proceed. All modules are pre-aligned
and tested.

K4 Key Specs and Features

  • Size: 4.5”Hx13.5”W,10”D
  • Weight: Approx.10lbs
  • SupplyVoltage: 12-15VDC
  • Current: ~2ARX,~18-23ATX
  • FrequencyRange: 100kHz-54MHz(VHF/UHFrangetobe determined*)
  • Stablility: +/-0.25ppm(TCXO) Modes: CW, SSB, AM, FM, Data
  • LCD: 7”color;touch&mousecontrol Text modes: CW, PSK31/63, RTTY KAT4ATU:
  • 10:1+range;3ant.jacks RXantennasources: Upto5
  • A-to-D Converter(s): 16 bits
  • I/O: USB-Ax3,USB-B(twovirtualcomports+audio),RS232(DE9), Ethernet, HDMI. front/rear mic, front/rear phones, LINE in/out, speakers,PTTin,KEYout,paddle,key, ACC,12Vout.
  • CWQSK: Silent,PIN-diodeswitched
  • Other: RX/TX EQ, real-time clock,100% remote control including panadapter data, remote antenna switch control*, custom in-box software apps*

Models (K4 & K4D upgradeable by the user at any time)

  • K4: Basic K4 transceiver provides 160-6 m, all-mode coverage; 100 W output; five receive RF sources; and wideband dual watch, allowing the main and sub receivers to be set for the same or different bands.
  • K4D: Adds KDIV4 option, with a second set of band-pass filters and additional direct- sampling ADC module. This allows the two receivers to use different antennas – a requirement for diversity receive. Having two sets of band-pass filters also optimizes signal handling when the receivers are on different bands and/or antennas.
  • K4HD: Includes all of the above, plus our dual superhet module, the KHDR4. Ideal for competitive field day, contesting, and DXpedition stations. Each superhet receive section includes two crystal filters: one SSB/data bandwidth, one CW bandwidth. The superhet’s 8 MHz IF has excellent dynamic range, so additional crystal filters are not required.

The Hermes-Lite SDR: an open source QRP transceiver based on a broadband modem chip

Note: This is a cross-post from the SWLing Post.

Many thanks to Pete (WB9FLW), who shares the following:

Don’t know if you are familiar with this project, a full blown 5 watt HF SDR Transceiver for less than $300!

No sound cards, DUC/DDC architecture.

Here’s the project description by Steve Haynal via YouTube:

The Hermes-Lite is a low-cost direct down/up conversion software defined amateur radio HF transceiver based on a broadband modem chip and the Hermes SDR project. It is entirely open source and open hardware, including the tools used for design and fabrication files. Over 100 Hermes-Lite 2.0 units have been successfully built.

The FOSSi Foundation is proud to announce Latch-Up, a conference dedicated to free and open source silicon to be held over the weekend of May 4th and 5th in Portland, Oregon, USA. Latch-Up: a weekend of presentations and networking for the open source digital design community, much like its European sister conference ORConf. Produced by NDV.

Click here to view this presentation on YouTube.

Fascinating! Thank you for sharing, Pete!

Vibroplex to distribute SSB-Electronic products in US & Canada

buglogo_betsyI’ve just received word that Vibroplex is partnering with the European manufacturer SSB-Electronic to offer products like the Zeus ZS-1 SDR and Ecoflex cable to customers in the USA and Canada.

Vibroplex has stated that they are “offering introductory pricing for all SSB-Electronic products from now through the Dayton Hamvention will be posted [on the Vibroplex website] in the near future.  The complete SSB-Electronic product line will be available for shipment approximately April 21st.”

Read full details about this in the Vibroplex press release below:

VIBROPLEX LLC TO DISTRIBUTE SSB-ELECTRONIC PRODUCTS IN UNITED STATES AND CANADA

The Zeus ZS-1 SDR transceiver
The Zeus ZS-1 SDR transceiver

Top-of-the-line Ecoflex™ coaxial cable, the Zeus ZS-1 SDR transceiver and a revamped line of VHF preamps and accessory equipment are now available for delivery.

KNOXVILLE, TN. April 8, 2014 – SSB-Electronic GmbH and Vibroplex LLC are pleased to announce an exclusive agreement for Vibroplex to distribute the SSB-Electronic product line in the United States and Canada.

Already #1 for coaxial cable sales in the European Amateur Radio market, SSB’s EcoFlex™ cable features the lowest loss characteristics of any commercially available non-hardline cable and for price vs. loss characteristics tops many available small hardlines. EcoFlex™ is available in 6 different versions to meet any RF need through 6-8 GHz dependent on cable version. Need maximum signal delivered from the amp to the antenna? This will meet your needs.

SSB is well-known for their range of VHF high performance products including both standard and auto-switchable receive preamps, sequencers and switches. A completely revamped product line has been released for 2014.

The new Zeus ZS-1 SDR transceiver features outstanding specifications and an easy-to-use graphical user interface. This exciting new product will have a feature presentation at the upcoming Dayton Hamvention™.

Visit the distribution webpage at www.vibroplex.com for complete information.

About Vibroplex LLC:

Vibroplex is the oldest continuously operating business in Amateur Radio, in their 109th year. In addition to manufacturing a line of Morse Code keys for the hobby, they also currently distribute products for German radio companies Spiderbeam GmbH and Folding Antennas on an exclusive basis in the United States and Canada.

Contact:

VIBROPLEX LLC
Scott E. Robbins
2906-A2B Tazewell Pike
Knoxville, TN 37918 USA
(865) 309-5073
www.vibroplex.com
www.spiderbeam.us

HackRF: an open source SDR transceiver

HackRF prototype (Source: ossmann.blogspot.com)
HackRF prototype (Source: ossmann.blogspot.com)

[From my shortwave radio blog…]

Michael Ossmann is making a business out of developing and producing open-source hardware.

His latest creation is called HackRF, and in less than a day, it has been fully backed on Kickstarter raising over $290,000 US with 25 days left to go in the campaign (at time of posting). Backers can contribute to this campaign with some confidence as Ossmann has successfully delivered products from Kickstarter in the past.

What makes HackRF unique is the fact that the stand alone unit can operate between 30 MHz and 6 GHz; a frequency range substantially wider than any SDR currently on the market. Indeed, when combined with the Ham It Up converter, the HackRF will also cover HF bands and lower.

Additionally, HackRF is a fully open-source transceiver; applications are limited only to a developer’s imagination. You could potentially use HackRF for ham radio, radio astronomy, scanning, shortwave radio listening, remote control applications, wide band monitoring, and commercial/industrial applications. If you use two HackRFs in tandem, they’ll even work in full-duplex applications.

Though the project is fully-backed, you can still support HackRF in the Kickstarter phase and save a bit on the eventual retail cost of the unit. Production units are expected to ship early 2014. Check out the HackRF Kickstarter video below:


Additional information:

Advances in Software Defined Radios could (will) change our wireless world

(Photo Source: New Geography)

Note that I’m not speaking strictly of the HF spectrum here. But mark this:  a radio revolution is, right now, in the making. ARS Technica just last week published an article entitled, “How software-defined radio could revolutionize wireless” in which the authors argue that software defined radios (SDRs) might not only open the door to new uses for our radio spectrum–uses we can’t currently fathom!–but also open the door to unlimited free innovation.  Innovation in the form of experimental hacking, much of which could simply fall below or outside of the FCC and other spectrum governing bodies, could become the province of literally anyone who wants to give it a go.

The article takes the reader through the evolution of SDRs and introduces a company manufacturing a product that could be to the radio spectrum and wireless communications what Apple became to personal computing.

I typically quote my favorite parts of an article, but this one is so very well-written and comprehensive, you really will want to read it in its entirety.  Click here to read, “How software-defined radio could revolutionize wireless“–and let your imagination take flight.

[Note that this is a cross-post from my shortwave radio blog, The SWLing Post]