Category Archives: Ham Radio

2019 Hamvention photos: Friday Flea Market

This morning, we’re about to head out to the Greene County Fairgrounds for the final day of the 2019 Hamvention. The past two days have been amazing and, as always, it’s been a pleasure to meet so many SWLing Post readers and contributors–thank you for stopping by!

Below, I’ve posted photos I took at the Hamvention Flea Market Friday morning. Note that most of these photos were taken prior to the flea market opening. Once again, I was most impressed with the number of vintage radios on display. Although it had rained early in the morning, it completely subsided by 7:00 AM so the grounds were in great shape by the 9:00 AM opening time.

2019 Hamvention Flea Market Photos

Click on the thumbnail images below to expand each photo. I’ve tried to include price tags when available. I plan to post inside exhibit photos tomorrow.


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RSGB 2018 Convention Lecture: DC to Microwaves on your smartphone

(Source: Southgate ARC)

The presentation by Noel Matthews G8GTZ on the Farnham WebSDR given to the 2018 RSGB Convention is now available on YouTube:

Click here to view on YouTube.

This presentation gives an overview of the Farnham WebSDR, available at http://farnham-sdr.com/ which currently covers the LF bands through to 10GHz.

The presentation describes the system architecture and antennas currently used on each band and how the team has used RTL dongle receivers, available for under £10, to give good RF performance on all bands from DC to 10GHz. There is a demonstration of the SDR in use on both PC and smartphone.

First Look: Elecraft K4 photos and preliminary information

The new Elecraft K4

Today, prior to the open of the 2019 Hamvention, I had an opportunity to hang with the folks at Elecraft and grab some photos of their newest transceiver: the Elecraft K4 direct-sampling SDR (click here to read the announcement).

Elecraft has now published a K4 product page on their website with information about pre-orderswith information about pre-orders. In short, the base model—which includes two full receivers—starts at $3999 US.

Wayne Burdick told me that they expect to start shipping the K4 by the end of 2019.

I snapped a number of photos of the two engineering prototypes of the K4 this morning in Building 1 at the 2019 Hamvention.

Elecraft K4 Photos

Click on the images below to enlarge:

 

 

Elecraft introduces the K4 high-performance direct-sampling SDR

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 HF transceiver based on a broadband modem chip

Many thanks to SWLing Post contributor, Pete Eaton, who writes:

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!

Going to the 2019 Hamvention? Stop by booth 6510!

For the tenth year in a row, fellow volunteers and I will be representing the charity Ears To Our World (ETOW), at the Hamvention now in Xenia, Ohio.

You can find us at booth 6510. (Click here for a map.)

I always enjoy meeting SWLing Post readers who stop by our booth to introduce themselves!

If you’re not familiar with Ears To Our World and our mission to empower children and teachers in the third word through radio and other technologies, check out our website.

Note that this year we will also give away our HumanaLight kits to those who donate $10 or more to ETOW (while supplies last). 

Look forward to meeting you in Xenia!

-Thomas (K4SWL)

Photo Gallery: Stephen makes a pilgrimage to the Duga site

Many thanks to SWLing Post contributor Stephen Cooper who shares photos from his recent visit to the Duga Soviet Union era over-the-horizon (OTH) radar system near Chernobyl.

The following photo gallery contains images of the antenna, control room, training room and server room. Click on the thumbnails below to enlarge images and browse:

What an amazing site, Stephen! Thank you for sharing your photo tour with us.

Readers: Stephen is also an application developer and the kind fellow behind Shortwave.am, Interval Signal Ringtones for Android, and the Shortwave Radio Schedules app. Check them out!