On Monday, I took the new Mission RGO One transceiver to the field and attempted a POTA (Parks On The Air) activation.
I just published a detailed post including a number of RGO One photos on my other radio blog, The SWLing Post.
In short? Although it’s early days, the RGO One is a promising rig and I’m very pleased with the ergonomics, functionality, and features. It’s very well suited for field operations weighing in at only five pounds and can comfortably operate up to 50 watts if you need a little extra power. I’m looking forward to activating a number of parks this year with the RGO One!
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.
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.
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.
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.
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.
Many thanks toPete (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.
Thomas, Adam of CR Kits is now taking orders for his FT8 Transceiver Kit and the price is very reasonable.
From Adam at CR Kits:
FT8 transceiver kit
Folks, I start to take email order now. The introductory price is 39 USD for kit including shipping to worldwide. As in the introductory period, you will get audio cable options for free. The earliest possible shipment date is now improved to May 13.
You can directly PayPal to firstname.lastname@example.org and let me know 40m or 20m (80m not ready yet). I will ship based on the sequence of receiving your payment. I may delay shipment for one week or two due to workload.
This is the spec so far:
Summary: Crystal controlled single frequency DSB transceiver for 20m (14.074MHz), 40m (7.074MHz) or 80m (3.573MHz), other frequencies could be added per requestPower supply: 10-14V DC regulated power supply or battery pack, 12V is recommended, center positive, reverse polarity protection availableCurrent consumption in RX: about 15mA at 12VCurrent consumption in TX: about 300mA at 12VRF output: about 1W for 40m band at 12V, and a bit less for 20m bandSpurious suppression: no worse than -50dBcAntenna connector: BNC connector, 50 ohmAudio in connector: 3.5mm mono, at least 600mV to activate VOX, connects to headphone connector at PC sound card, no dedicated PTT connector is requiredAudio out connector: 3.5mm mono, connects to microphone connector at PC sound cardAmber LED: TX statusGreen LED: RX statusFrequency accuracy: -600 Hz ~ + 200 HzFrequency stability: Okay for FT8 mode per test. If the optional heater resistor R20* is added, after warm up, long term frequency stability in 10 min will be improved at the cost of acceptable short term frequency stability sacrifice in 30 sec. Thanks, Adam
This is a simple and experimental modification that transforms a QCX into a (Class-E driven) SSB transceiver. It can be used to make QRP SSB contacts, or (in combination with a PC) used for the digital modes such as FT8. It can be fully-continuous tuned through bands 160m-10m in the LSB/USB-modes with a 2400Hz bandwidth has up to 5W PEP SSB output and features a software-based full Break-In VOX for fast RX/TX switching in voice and digital operations.
The SSB transmit-stage is implemented completely in a digital and software-based manner: at the heart the ATMEGA328P is sampling the input-audio and reconstructing a SSB-signal by controlling the SI5351 PLL phase (through tiny frequency changes over 800kbit/s I2C) and controlling the PA Power (through PWM on the key-shaping circuit). In this way a highly power-efficient class-E driven SSB-signal can be realized; a PWM driven class-E design keeps the SSB transceiver simple, tiny, cool, power-efficient and low-cost (ie. no need for power-inefficient and complex linear amplifier with bulky heat-sink as often is seen in SSB transceivers).
An Open Source Arduino sketch is used as the basis for the firmware, the hardware modification bypasses the QCX CW filter and adds a microphone input in-place of the DVM-circuit; the mod is easy to apply and consist of four wire and four component changes and after applying the transceiver remains compatible with the original QCX (CW) firmware.
This experiment is created to try out what can be done with minimal hardware; a simple ATMEGA processor, a QCX and a software-based SSB processing approach. It would be nice to add more features to the sketch, and try out if the QCX design can be further simplified e.g. by implementing parts of the receiver stage in software. Feel free to experiment with this sketch, let me know your thoughts or contribute here: https://github.com/threeme3/QCX-SSB There is a forum discussion on the topic here: QRPLabs Forum
Note that the following is a cross-post from my other radio blog, The SWLing Post:
Many thanks to SWLing Post reader and author, DM Barrett (N4ECW), who recently shared the following press release which features his latest book:
FOR IMMEDIATE RELEASE
EQUINOX Blends Science Fiction And Amateur Radio
1 May 2019 (Tampa, Florida)
A new science fiction narrative, EQUINOX, has taken amateur and shortwave radio into the cultural mainstream in its version of a limited alien invasion story line.
“It’s been quite a while since the world depended on amateur and shortwave radio as lifelines. In EQUINOX, both are critical for the success of The Resistance.” – DM Barrett, EQUINOX author
DM Barrett, callsign N4ECW, lives and breathes amateur radio. He is well known in the ham radio community having developed and manufactured several different specialized radio antennas through his former company, Transworld Antennas. He holds two earned doctorates with majors in law, economics, and religion.
The EQUINOX story line begins on a warm, slightly breezy day on Florida’s east coast as the vernal equinox marked the beginning of spring. Suddenly, there was a thunderous crash, a blinding light, and a vortex swirling in the blue Atlantic. The invading alien army arrived. The world surrendered. The Resistance made a stand.
When the science fiction novel was recently released as a Kindle Unlimited eBook, it moved steadily into Amazon’s top ten science fiction eBooks in the United States, United Kingdom, Germany, Canada, and Australia. After only a few days, the paperback version of EQUINOX was ranked in Amazon’s top third for science fiction paperbacks.
Adam BD6CR of CR Kits is getting close to releasing the FT8 DSB Transceiver. Below is some preliminary information:
D4D: A simple QRP transceiver for FT8
Adam Rong, BD6CR
D4D stands for DSB transceiver for Digital modes. It is a Double Sided Band transceiver kit designed for digital modes, especially for FT8. If have chance to try FT8, you will be amazed by the strong decoding capability offered by the communication protocol, digital signal processing and software. I still remember clearly a YouTube video by W6LG who communicated with bulbs. I started to think how much the transceiver could be simplified if you have a moderate antenna like a full sized dipole or EFHW.
A DSB transceiver is much simpler than a usual SSB transceiver, however it was never used for FT8 as far as I know. I did some experiments on my Choc perf board. I started with a direct conversion receiver for FT8 and it worked okay. Then I made a DSB transmitter and the transmitted signal can be decoded. By referring to the designs of AA7EE, VK3YE and ZL2BMI, I combined them using only one NE602 and a PTT switch and it gave me success to make a few FT8 QSO’s.
Personally I really enjoyed it because a manual PTT switch will save power consumption and circuit complexity, but you will need to well sync with computer, although it was not really a problem for me. Per request from a few hams, I found a VOX control circuit and modify the hold time to be compatible with FT8, and I put them together and made a few improvements on the signal purity and frequency stability, and it became our D4D. Do we have to worry about the unwanted Lower Side Band? Maybe, but for a transmitter of 1-watt, it is not really a big problem. Is it just a toy for a transmitter of 1-watt and only half of the power will be effective? Not really, as I can easily make a few QSO’s as far as 1500 miles range for 40-meter band.
Here is the brief specifications I have measured (subject to change without notice):
Summary: Crystal controlled single frequency DSB transceiver for 20m (14.074MHz), 40m (7.074MHz) or 80m (3.573MHz), other frequencies could be added per request Power supply: 10-14V DC regulated power supply or battery pack, 12V is recommended, center positive, reverse polarity protection available Current consumption in RX: 15mA Current consumption in TX: about 260mA(?) at 12V, and about 300mA at 13.8V RF output: about 1W for 20m band at 12V, a bit more for lower bands like 40m and 80m Spurious suppression: no worse than -50dBc Antenna connector: BNC connector, 50 ohm Audio in connector: 3.5mm mono, at least 600mV to activate VOX, connects to headphone connector at PC sound card, no dedicated PTT connector is required Audio out connector: 3.5mm mono, connects to microphone connector at PC sound card Amber LED: TX status Green LED: RX status Frequency stability: Okay for FT8 mode per test. If the optional heater resistor R20* is added, after warm up of about 3 min, long term frequency stability in 10 min will be improved at the cost of acceptable short term frequency stability sacrifice in 30 sec.
Let us briefly go through the circuit: The input audio will activate the VOX circuit of D2 (1N4148), Q5 (2N3906), Q6 (2N3904), Q7 (2N3904) and Relay. The relay is a DPDT type and controls both antenna and power supply. The LPF consists of L2, L3 and surrounding capacitors, and it is switched to either transmitter output or receiver input. The power supply is polarity protected by D1 (1N5817) and switched to either receiver circuit or transmitter circuit. The receiver circuit is only for audio amplifier consists of Q1 (2N3904) and optional heater resistor R20*, while the transmitter circuit is for RX muter Q8 (2N3904), TX driver Q3 (2N3904) and TX final Q4 (BD139). X1 is a filter in the receiver front end to help eliminate strong broadcast interference, and X2 is the crystal for the built-in oscillator in U1 (NE602). U2 (78L05) is the 5V regulator for U1, and Q2 (2N3904) is a buffer amplifier in the TX chain.
Thanks for sharing this, Pete! What a simple transceiver concept!
Joe Taylor K1JT has announced a new digital mode, FT4, which is 2.5 times faster than FT8
FT4 is an experimental digital mode designed specifically for radio contesting. Like FT8, it uses fixed-length transmissions, structured messages with formats optimized for minimal QSOs, and strong forward error correction. T/R sequences are 6 seconds long, so FT4 is 2.5 × faster than FT8 and about the same speed as RTTY for radio contesting.
FT4 can work with signals 10 dB weaker than needed for RTTY, while using much less bandwidth.
FT4 message formats are the same as those in FT8 and encoded with the same (174,91) low-density parity check code. Transmissions last for 4.48 s, compared to 12.64 s for FT8. Modulation uses 4-tone frequency-shift keying at approximately 23.4 baud, with tones separated by the baud rate. The occupied bandwidth (that containing 99% of transmitted power) is 90 Hz