FT-8 New digital mode 8-FSK modulation

It’s still in beta testing, but FT8 — the latest digital bauble to capture the imagination of the Amateur Radio community — has been luring away many of those already using the popular JT65 “weak-signal” mode. FT8 is included in a beta release of WSJT-X, version 1.8.0-rc1. Among its biggest advantages is a shorter transmit-receive cycle, meaning quicker contacts. The notes for the “candidate” release say that FT8 offers “sensitivity down to –20 dB on the AWGN channel.” Contacts are four times faster than with JT65 or JT9, and an entire FT8 contact can take place in about 1 minute.

The new mode is named after its developers, Steven Franke, K9AN, and Joe Taylor, K1JT. The numeral designates the mode’s 8-frequency shift keying format. Tones are spaced at 6.25 Hz, and an FT8 signal occupies just 50 Hz. Unlike JT65 or JT9, transmit and receive cycles in FT8 each last about 15 seconds. Like JT65, FT8 requires accurate time synchronization. An auto-sequencing feature offers the option to respond automatically to the first decoded reply to your CQ.

“FT8 is an excellent mode for HF DXing and for situations like multi-hop Es on 6 meters, where deep QSB may make fast and reliable completion of QSOs desirable,” Taylor’s release notes assert.

The beta release came out just days before the July CQ VHF Contest and proved to be a boon to many operators who took advantage of FT8 on 6 meters. In a limited outing for the CQ VHF, Frank Donovan, W3LPL, made 22 FT8 contacts on 6 meters, “during which the FT8 software reported SNRs from my receiver below –10 dB (measured in a 2,500-Hz bandwidth). Some of the 22 QSOs may have been difficult to complete on CW.”

Enthusiasts will have to wait a little longer for Logbook of The World (LoTW) to accept FT8 contacts as FT8 contacts. Because FT8 is still in beta, it has not yet been added to the ADIF tables. Configuring TQSL to automatically map FT8 contacts to “DATA” will enable users to upload FT8 contacts now, and confirmations will be valid for DXCC Digital, VUCC, WAS Digital, and WPX Digital awards. A new TQSL configuration will be released once the new mode has been accepted to ADIF, which could happen within a week.

Important characteristics of FT8:

– T/R sequence length: 15 s
– Message length: 75 bits + 12-bit CRC
– FEC code: LDPC(174,87)
– Modulation: 8-FSK, keying rate = tone spacing = 5.86 Hz
– Waveform: Continuous phase, constant envelope
– Occupied bandwidth: 47 Hz
– Synchronization: three 7×7 Costas arrays (start, middle, end of Tx)
– Transmission duration: 79*2048/12000 = 13.48 s
– Decoding threshold: -20 dB (perhaps -24 dB with AP decoding, TBD)
– Operational behavior: similar to HF usage of JT9, JT65
– Multi-decoder: finds and decodes all FT8 signals in passband
– Auto-sequencing after manual start of QSO

*Comparison with slow modes JT9, JT65, QRA64:* FT8 is a few dB less
sensitive but allows completion of QSOs four times faster. Bandwidth is
greater than JT9, but about 1/4 of JT65A and less than 1/2 QRA64.

*Comparison with fast modes JT9E-H:* FT8 is significantly more
sensitive, has much smaller bandwidth, uses the vertical waterfall, and
offers multi-decoding over the full displayed passband.

*Still to come, not yet implemented:* We plan to implement signal
subtraction, two-pass decoding, and use of “a priori” (already known)
information as it accumulates during a QSO.

Three extra bits are available in the message payload, with uses yet to
be defined. We have in mind special message formats that might be used
in contests, and the like. Your considered suggestions for use of these
bits are very welcome!

K1JT, K9AN, and G4WJS have conducted on-the-air tests of FT8 with
excellent results. We’re now at a stage where tests under a wider range
of conditions are desirable. If you can build WSJT-X from source code
revision r7750 or later, and would like to help, please do so and report
your results to us! Pre-built installation packages will be made
available after further testing is completed.


FT-8 New digital mode 8-FSK modulation

Paul Leicester | MØFOX | Chesterfield UK | IO93HE | Icom IC-7300

RTL-SDR’S WITH THE R820T2 TUNER AND 2X TELESCOPIC ANTENNA

R820T2 RTL-SDRs on Amazon.com (currently for US customers only sorry!) and are currently running a $2 off promotional sale which will expire January 31, or until the first batch of stock runs out. Compared to the other choices our RTL-SDR Blog branded units come with several improvements which we list below.

  • Use of the R820T2 tuner which has been shown to have slightly better noise performance and give better SNR compared to the standard R820T chip.
  • Use of improved component tolerances which help the circuit to operate at its optimum.
  • Use of a surface mount 28.8 MHz oscillator instead of the “can” type. We believe this will reduce the PPM offsets to below 30 in most dongles, but note we can not guarantee this.
  • Improved “full braid” coax cable on the antenna base which has significantly lower loss compared to the coax used on other brand RTL-SDR stock antennas.
  • Comes with 2 x telescopic antennas. 1 x 9.5 cm to 31.5 cm telescopic antenna and 1 x 20 cm to 1.5 m telescopic antenna. Great for beginners to receive a wider range of frequencies without buying extra antennas.
  • No IR LED. The IR LED is useless for SDR operation and the long legs on the LED may pick up interference.
Paul Leicester | MØFOX | Chesterfield UK | IO93HE | Icom IC-7300

Hytera launches latest DMR handheld radio PD985

Hytera, a world leading solution provider of Professional Mobile Radio communications, has launched its latest DMR (Digital Mobile Radio) handset, the PD985, the flagship professional device at the top of a strong DMR portfolio. The PD985 offers an exceptional audio experience through noise cancellation technology, as well as boasting new features including full duplex calls (*) recording capability via Micro SD card (*) Bluetooth 4.0 for audio or data (*) and single frequency repeater to increase coverage(*). The PD985 will be available in UHF (350-527Mhz), with a VHF version to follow in 2017.

“We are proud to announce the launch of the PD985” said G.S. Kok, Senior Vice President of Hytera. “The PD985 is a significant addition to our existing DMR radio portfolio. We have succeeded in adding a series of cutting-edge innovations and designs into this new model to make it a full-featured radio to satisfy our customers’ increasing demand in terms of functionality and user experience.”

The addition of the PD985 positions Hytera with the most complete DMR radio portfolio to meet diversified requirements, from simple, reliable and cost-effective handsets (PD3 and PD4 series) to rugged and feature-rich solutions (PD5 and PD6 series), up to the high-end, professional systems radios (PD7, PD9 and X1 series). The whole portfolio offers display and non-display, GPS and non-GPS, UHF and VHF versions to allow customers to select the best handset for their daily operation and mission critical scenarios.

Paul Leicester | MØFOX | Chesterfield UK | IO93HE | Icom IC-7300

Motorola Solutions Files Patent Infringement Trade Secret Misappropriation

Motorola Solutions Files Patent Infringement and Trade Secret Misappropriation Complaints Against Hytera Communications


Patent Infringement and Trade Secret Misappropriation Complaints Filed in U.S. District Court

Motorola Solutions is Committed to Protecting its Valuable Intellectual Property Against Illegal Infringement and Copying

CHICAGO – March 14, 2017 – Motorola Solutions, Inc. (NYSE: MSI) (“Motorola Solutions” or the “Company”) today announced it has filed complaints in the U.S. District Court for the Northern District of Illinois against Hytera Communications Corporation Limited (SHE: 002583) (“Hytera”) of Shenzhen, China. The complaints assert that Hytera’s two-way radios, base stations, repeaters and dispatch systems, as well as its related commercialization and sales activities, are infringing patents owned by Motorola Solutions and utilizing stolen Motorola Solutions trade secrets.

Motorola Solutions believes that Hytera is intentionally infringing its intellectual property and misappropriating its trade secrets, which has enabled Hytera to compete unfairly by bypassing investment in innovation.

Mark Hacker, general counsel and chief administrative officer of Motorola Solutions, said, “Motorola Solutions has a long and distinguished track record of developing industry-leading products and technologies, reflecting our significant investments in research and our commitment to innovation. We are proud to have built an extensive portfolio of more than 4,000 patents, including the patents at issue in these lawsuits, which were developed by Motorola Solutions’ world-class engineers.”

Mr. Hacker continued, “We believe it is clear, and we are confident the Courts will agree, that Hytera’s product portfolio and marketing materials are based on Motorola Solutions’ proprietary intellectual property. Brazen copying and blatant, willful infringement of this sort create an unfair playing field and threaten the industry’s ability to innovate. We will use every means available to vigorously defend the Company’s valuable intellectual property, while continuing to drive innovation and technical excellence for the benefit of our customers around the world.”

Hytera’s illegal behavior was assisted by three engineers who resigned from the Company to join Hytera, where they had key roles in developing Hytera’s infringing products using misappropriated Motorola Solutions technologies and continue in senior-level positions today. In the period leading up to their resignations, through a series of serious misrepresentations and carefully planned illegal acts, these engineers maliciously accessed, downloaded and transferred more than 7,000 highly confidential files related to Motorola Solutions’ technologies, including confidential technical, marketing, sales, legal and other types of trade secret materials. Subsequently, Hytera began illegally manufacturing and marketing a line of products and technologies containing technologies invented, designed, developed and in some cases patented by Motorola Solutions.

Motorola Solutions is seeking to enjoin Hytera’s continued infringement and misappropriation by stopping its sales of key products in the United States and importation of those infringing products into the United States. The Company is committed to ensuring that its intellectual property rights are protected around the world.

Paul Leicester | MØFOX | Chesterfield UK | IO93HE | Icom IC-7300