New Open Source Data Mode FSQ

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Con Wassilieff ZL2AFP has developed a new fast simple chat data mode for use on HF and VHF 

FSQ is a Fast Simple QSO mode for MF/HF. It works well under NVIS and sunrise/sunset conditions on the lower bands, and also works well for short skip on higher bands. It can also be used on VHF FM, and clearly has a much wider useful range of operating conditions that other more conventional digital modes. Sending speed can be varied between 20 and 60 WPM.

Screenshot of the ZL2AFP FSQCALL software with FSQCALL turned off

FSQ is designed for simple but effective 'Chat' operation, rather like phone text messaging or Skype™ chat; fast and easy to use. You don't use 'overs' as you would with a conventional digital or voice mode. It is highly suited to net operation. You just type a sentence and press Enter. 

An important factor in the design of FSQ is that no synchronising process is required to locate and decode the received characters. Lack of sync means that reception is much less influenced by propagation timing changes that affect almost all other modes, since timing is quite unimportant; it almost completely eliminates impulse noise disruption; and it also contributes to very fast acquisition of the signal (decoding reliably within one symbol of start of reception). Fast acquisition removes the need for addition of extra idle characters at the start of transmission, and this leads to a very slick system. Add high resistance to QRM and QRN, thanks to the low baud rate, and you have a system so robust that it does not need error correction. 

Sensitivity is believed to be about -13 dB SNR at 6 baud, and -16 dB SNR at 3 baud. That's about 10dB better and several times faster than 12 WPM Morse. 

FSQ is NOT compatible in any way with EXChat or DominoEX. While also a Chat mode, it uses a completely new and revolutionary protocol.

FSQ - http://www.qsl.net/zl1bpu/MFSK/FSQweb.htm

Direct download link - http://www.qsl.net/zl1bpu/SOFT/FSQCALL.zip

Radio Astronomy and SDR Dongles

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David Morgan 2W0CXV has released several papers covering the use of the RTL-SDR Dongle in radio astronomy 

In 2011 David described the equipment configuration and software involved in setting to work a small 3m diameter amateur radio telescope using the FUNcube Dongle Pro software defined radio receiver.

At the end of 2014 he published a paper dealing with the setting up and use of a RTL-SDR dongle to receive meteor pings from the Graves Radar on 143.050 MHz.

He has now released two new papers covering the measurement of signal strength and  RF noise sources with the RTL-SDR.

Download David’s papers - http://www.dmradas.co.uk/Downloads.html

You can join the BAA Radio Astronomy Yahoo Group - http://groups.yahoo.com/group/baa-rag

UK HF Propagation Prediction Maps

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Steve Nichols G0KYA, chairman of the RSGB's Propagation Studies Committee, has updated his UK HF coverage prediction maps for this quarter using the current smoothed sunspot numbers (SSNs).

UK_HF_Propagation_Maps

The maps for April to December can be used as being representative, but will be updated as and when the SSNs are updated later in the year.

Steve said that on the current evidence it looks like we passed the peak of Sunspot Cycle 24 in the Spring of 2014. However, the cycle still seems to have some life left in it.

The peak solar flux index (SFI) for the cycle occurred on 23 rd October 2014 at 227, although there were plenty of other times when it bettered 200, including January 2014, October and December 2014.

On an annual basis, 2014 had the highest average daily sunspot numbers of any year since 2002, according to the ARRL, although the peak solar flux indices were higher in 2002, hitting 261 on 29th January 2002.

The highest peak solar flux indices of cycle 23 were actually seen in 2001, with 283 being reached on 26 th September 2001. This cycle has been poor in comparison.

But what next? Steve says that what has been very apparent is the general increase in solar flares and coronal mass ejections (CMEs) recently. This has led to disturbed geomagnetic and HF conditions and is typical of the downward trail away from a sunspot maximum.

Over the next quarter we can expect to see overall sunspot numbers decline slightly, with solar flare and CME activity remaining high. Expect to see SFI numbers in the range 120-180, still good enough to provide good openings to DX on the higher bands at times.

We may see the cycle peak up yet again before it finally tails away, but are we likely to see the SFI go above 200 again? Who knows.

G0KYA's UK HF prediction maps - http://www.infotechcomms.net/propcharts/ and his blog at  www.g0kya.blogspot.co.uk