The AM Forum

Band Watch => 17 Meters => Topic started by: W1AEX on March 23, 2012, 03:47:59 PM



Title: 17 Meter Intrusion - Pulse Noise
Post by: W1AEX on March 23, 2012, 03:47:59 PM
This pulse noise was heard at several locations in the northeast. I would be interested to know where else it might have been heard. The recording is roughly 40 seconds long and illustrates the 20kc bandwidth of the signal as it pulsed in an upward moving wave-like motion. The recording was made in CT on 3-23-2012 at 18:04 UTC.

http://www.youtube.com/watch?v=HWKRB4yZ-lM&feature=youtu.be&hd=1

Thanks for any reports you can offer,

73,

Rob W1AEX


Title: Re: 17 Meter Intrusion - Pulse Noise
Post by: k4kyv on March 23, 2012, 04:05:42 PM
Wonder if it might be coming out of Europe or Africa.  The pulse rate sounds like 50 cps to me just by ear. Is 17m a primary amateur allocation world-wide, or is it secondary?


Title: Re: 17 Meter Intrusion - Pulse Noise
Post by: W1AEX on March 23, 2012, 04:20:41 PM
I believe it's a primary allocation for amateur use world-wide. I did check the League chart and found nothing to indicate that this is not so:

http://www.arrl.org/frequency-allocations

You've got good ears Don. I sampled one second of the noise and counted the pulses. You are correct, it is a 50 cps source. I have received a number of emails indicating that this is OTHR emanating from either France or the Middle East. It does seem somewhat similar to a recording of OTHR made on the 30 meter band here:

http://www.youtube.com/watch?v=OD0mlxXbA0Y

Rob W1AEX
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands