Broad Spectrum RFI

Hey Guys,

This is a small post to report on a broad spectrum RFI (Radio Frequency Interference) that I've noticed since setting up my SWL radios and Antennas at my Brisbane QTH location. The RFI appears to start dead on 0900 AEST every morning and has a cycle of ~50 seconds and lasts for ~2-3 seconds burst. It appears to stop just before 1200 AEST.

The S-meter on both the Kenwood R1000 and ICOM R75 are pegged at S9+ for dipole antenna. So hoping that the magic of loop antenna would null out local RFI, I switched over to the Wellbrook ALA-1530 loop antenna and ..... BUGGER!!! its also pegged at S9+. Using the ICOM R75 I've tested each 500 khz between 2mhz and 60mhz and this RFI comes through them all.....

Here is a sample audio file of this RFI "0.5 mb : ~4min"

I'm not sure to what extent / distance this RFI is affecting and hope to take a drive round the area with the Sony Protable to see if I can hone in on the source.

If anyone has encountered or encountering a similar RFI pattern and could shed some possible light / answers I'd be most appreciated.

Cheers
Mark

05-Oct-2010 - Update 1

I've been monitoring the RF interefence from when I wake up til I hit the sack sometimes near midnight and besides the period ~08:55 AEST til ~11:00 AEST they was no other sign of the RFI.   Well that was until early this morning when I coun't sleep and got up just before 01:00 AEST to do some WSPR work and band scanning.  Just after 01:00 (else I hadn't noticed it while setting up) the RFI appeared to start, yep!!!!! and went on for an hour and I gave up and got back into bed......  Got up just after 0600 and the RFI was not there, until the normal time 08:55.. Ahhhhh!!!!!! 


I need to sort this out !!!


06-Oct-2010 - Update 2

Morning Guys,

I've just been for a walk round the neighbourhood and as soon as I was a few houses away from home I noticed the RFI was not audible. so I walked a circle and up an down the streets clockwise and wouldn't you know, the bloody last powerline power two doors down appears to be the source.  I used my portable with the antenna in its down and locked position and standing under this pole and the RFI blasted your ears off. if only I had walked anticlock wise doh!!!! :)

Walked to the poles either side of it and the rfi is there slightly  and onto poles further either side and nothing.

The pole feeds power to 4 homes and a street lamp.  I've got the pole number so now going to get in touch with the power company "Energex" and somehow provide them problem / fault report.

Fingers crossed

Many thanks
Mark

Louisiade Yacht Rally 2010

While testing out my new homebrewed 2 Turn and Single Turn 1.6m Diameter Magnetic Loop Antennas, I was monitoring 4483 khz on Saturday 11th September 2010 evening and it appears a maritime net was being run and a series of yachts where giving their positions just north east of Cairns. Catching the end of the 18:30 sked, I waited to the morning sked at ~ 0730 (I think) but again was not able to hear which yacht net was being run, although it was fun listening the previous night to the the net controller onboard the yacht "Sanctuary". It was the net controller's birthday and he had a few best wishes given.

Anyhows last night Sunday, I did a little googling after hearing "something yacht rally" and quickly located the yacht names and website for the "Louisiade Yacht Rally 2010". The basic idea of the event is a bunch of yachta leave Cairns for the "Louisade Archipelago's" east of PNG. It provides yachtmen that have not had much blue water experience a safe and fun means to expose themselves, their crew and their yachts to the open ocean.

Tonight Monday 13th September 2010, listening into the the 18:30 sked, we heard moajority of yachts in the sked, and it appears that some will start arriving tomorrow morning somethime. They have had great sailing conditions with only a few incidents causing a couple of the yachts to retire and head back to cairns.

At the end of the day, I think this event is a fantastic one, as the event promotes a fun and safe culture for those looking to get exposed to / sample blue water.

Here is a mp3 audio sample of the tail end of sked "click here - 1.3 mb : 12 mins".

Cheers
Mark