HFU HF Underground

Loggings => HF Beacons => Topic started by: Dag on April 01, 2015, 2341 UTC

Title: Short duration square wave 13554.91 kHz followed by "EH"
Post by: Dag on April 01, 2015, 2341 UTC

On April 1 2015 at 2330z I was monitoring 13554.91 kHz USB with ARGO QRS
spectrum display. There was no activity.  

At 2334z a square wave appeared for about for about 120 seconds, then stopped.  See the  link below for the waterfall capture. I started the QRS view within a second of the appearance of the signal.

At 2346z "EH" become started, about 10 hz lower exhibiting a slight drift occasionally, and has been steady for over an hour.   Maybe EH was in testing mode for a few minutes? I don't think so as the shape of the square wave on this unidentified signal doesn't match the "EH" square wave when viewed on the waterfall display. 

This is a screen shot of the short-duration square wave copied on 13554.91 kHz + 590 Hz:
http://1drv.ms/1CyFo4P

Dag

Title: Re: Short duration square wave 13554.91 kHz followed by "EH"
Post by: Dag on April 03, 2015, 2130 UTC

The square wave signal and the EH beacon are now on simultaneously at 2115z 03 APR 2015 as shown in this screen shot:
http://1drv.ms/19UxXeh

Dag