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

Motorola DM4600 / DM4601 MOTOTRBO Mobile two way radio

Motorola DM4600 / DM4601 MOTOTRBO Mobile two way radio

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From the delivery driver crisscrossing the city to the sanitation crew clearing streets, your employees work smarter and safer with the MOTOTRBO™ DM4000 Series mobile two-way radio.

This fully-featured mobile transforms your enterprise, delivering unrivaled voice and data communications with integrated Bluetooth audio and data*, integrated GPS*, text messaging and a full 4-line colour display with day/night mode to make reading work order tickets and text messages easier. You also get best-in-class audio that includes Intelligent Audio and a customisable voice announcement feature.

Best-in-class audio
Loud front-facing speaker and Intelligent Audio feature automatically adjusts the radio volume according to the environment’s noise level

Large, full colour display
Enhanced 5-line display features a flexible menu-driven interface. Icons and large easy-to-use navigation buttons ease message reading and menu navigation

Day/night display mode
Day mode displays improved resolution for easier viewing even in broad daylight, while night mode makes the screen easier to read in dark environments

Flexible configurations and easy use
Available in UHF and VHF frequency bands with 1000 channel capacity, large, easy to access volume knob and four programmable buttons with option to use one as an emergency button

Integrated GPS
Locate mobile work teams using integrated GPS (DM4601 model only)

Bluetooth data
Share real-time information by connecting radios to Bluetooth-enabled data devices (DM4601 model only)

Productivity-enhancing data applications
Features the industry’s largest application developer program to enable a wide variety of customised applications including: location tracking, work order ticket management, Bluetooth data, email gateways, dispatch, telephony and man-down

Text messaging
Send update messages to team members when radio communications need to be delivered without interrupting workers or guests

Embedded Bluetooth audio
Enables connectivity with wireless accessories including Motorola’s unique Operations Critical Wireless earpieces designed for rugged and reliable communications (DM4601 model only)

Capacity Plus
Single-site digital trunking system that maximises the capacity of your MOTOTRBO system. Use it to enable a high volume of voice and data communication for over a thousand users at a single site

IP Site Connect
A digital solution that uses the internet to extend the voice and data capabilities of MOTOTRBO. Use it to link up to 15 sites for communication among geographically dispersed locations, to create wide area coverage or enhance coverage at a single site with physical barriers

Emergency button
Orange P4 button can be optionally programmed to send an alert to a supervisor or dispatcher during an emergency situation

Transmit interrupt
Enables a user to interrupt another radio conversation to deliver critical communication exactly when and where it’s needed

Basic or enhanced privacy
Built-in scrambling for increased security (Programmable)


Motorola DM4600 / DM4601 MOTOTRBO Mobile two way radio

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

Hytera MD785/785G DMR Radio

Hytera MD785 UHF DMR Radio
Hytera MD785 UHF DMR Radio

Hytera MD785 UHF DMR Radio

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Hytera MD785/785G DMR Digital UHF VHF Radio

User-centered Design The large-size color display allows good visibility even under extremely strong light. And the seven programmable keys facilitate your communication in various conditions. Reliable Quality Hytera MD785/785G is strictly compliant with MIL-STD-810 C/D/E/F and IP54 standards, ensuring outstanding performance even under harsh environments. Superior..

This DMR mobile radio offers versatile digital functions and solid loud audio. With its ergonomic design, its easy to operate user menu system and its remarkable build quality, this is the ideal solution for all your DMR needs; whether it is mobile vehicle mounted operation, or for use in the shack.

  • Excellent voice transmission – Thanks to the simultaneous application of narrow band codecs and digital error correction, the Hytera MD785 offers you an outstanding audio quality in loud environments and in fringe areas of the repeater coverage
  • Dual mode – The Hytera MD785 features an analogue as well as a digital mode and is compatible with the currently used analogue repeater systems, thereby simplifying your transition into the digital age. This also means you don’t need to have two radios, have analogue and digital all in one.
  • Improved use of the radio spectrum – Thanks to the TDMA process the MD785 allows an assignment of the available bandwidth with double channel capacity. This results in a clear relief of the increasing spectrum scarcity
  • Secure communications – Besides the built-in encryption based on digital technology, the MD785 features advanced encryption options, e.g. 256-bit encryption and a scrambler function (optional)
  • Reliability and quality – The MD785 complies with the standards MIL-STD-810C/D/E/F/G and the degree of protection IP54 and offers a high degree of reliability even in rough environments
  • Versatile functionality – Besides the classic communication functions, the MD785 features numerous additional digital and optional functions, including text messages, individual calling and a lone worker function
  • Expansion port – Thanks to the built-in expansion port, the MD785 can be expanded by additional functions
  • Intuitive interface and key guidance – The high-resolution LCD screen offers a clear display, even under difficult light conditions. The large keyboard and ergonomic programmable keys allow this radio to be easily operated.

Hytera UK is a UK registered, wholly-owned subsidiary of Hytera Communications Co Ltd, founded in 2004. Located in Slough, Berkshire, Hytera has been dedicated to distributing analogue, DMR and Tetra radios for over 7 years. From the outset, Hytera UK has been committed to providing outstanding service and support to all partners and dealers. This has led to Hytera becoming one of the top radio providers worldwide.


Hytera MD785 785G DMR Radio Mototrbo UHF VHF Digital

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