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Audio recorded to 7300 SD card Waveforms analysed in Soundforge 11 Screen capture by pressing power button momentarily
Noise JO01GR  2017-10-12T07-19-59Z Random patterns Hexbeam, direct no tuner, heading NW

Attenuator on







Preamp 1 on






Preamp 2 on






Noise levels in a rural area, daylight, so no lighting SMPS buzz - beaming E, away from Chelmsford noise USB, AGC mid

NOTES for participants in the receiver reference noise project:

You can use any receiver - but the ICOM7300 is ideal and in use around the world in big numbers.

RF interference from LF to VHF is a fast growing global issue as more noisy SMPS appear in everything from LED lighting to rogue phone chargers , and broadband delivery using DSL sprays RFI everywhere. The authorities don't seem to understand that this pollution can have major and unanticipated consequences if it is not got under control.

Crucially - even if you don't think you have a noise problem today, you should create a "reference record" for comparison when you find your noise floor has slowly or suddenly crept up.

And this is not just about ham radio - how would you like to find your car alarm key fob won't work after dark - because a rogue SMPS in a neighbour's LED yard light blotted it out...?

The fact there are so many 7300 users now means we can gather reports and be fairly certain we are comparing like-with like.

If all you lovely people could gather info from your locations using file names in the format:-

[Grid location]-[band]-[notes]-[YYY-MM-DD]T[HH-MM-SS] ALL times Z/UTC please -

eg a screen grab file should be in teh form:


sound file:


Also please note the antenna type and direction - where relevant. We may add extra fields for this into the audio file record in due course - this is all work in progress. And we will then process and display on the evolving website that is in the works.


Solar Conditions and Geomagnetic Activity


from Solar Ham

Solar-terrestrial indices for 11 October follow.
Solar flux 70 and estimated planetary A-index 30.
The estimated planetary K-index at 1500 UTC on 12 October was 5.

Space weather for the past 24 hours has been minor.
Geomagnetic storms reaching the G1 level occurred.

Space weather for the next 24 hours is predicted to be minor.
Geomagnetic storms reaching the G1 level are expected.


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