LF: Re: Signals on 136/7 - DFCW timing

["Markus Vester" <markusvester@aol.com>]

Hi Chris,

 

2 min 10 sec would actually match my transmission timing. The calculated symbol duration was 60.186 seconds, in a sequence of 2 on, 1 off, 2 on, 5 off. There are no gaps between consecutive dashes but 180 degree phase shifts, which should look like tiny knots in a spectrogram line. Actual keydown times were slightly longer because of a 5 second overhang of the smoothed ramps at turnon and turnoff.

 

For comparison, I have uploaded two local grabber shots from Sunday night:

http://freenet-homepage.de/df6nm/TA/testEu0811030000.png (timescale 6 pixels/minute),

http://freenet-homepage.de/df6nm/TA/test0811022220.png (40 pixels/minute).

 

I won't be able to transmit during this week but perhaps again next weekend.

 

Best wishes

Markus, DF6NM

----- Original Message -----

From: Chris

To: RSGB lf Group

Sent: Tuesday, November 04, 2008 1:30 PM

Subject: LF: Signals on 136/7

Hi All,

Thanks to those who commented about my 'mystery' signal - Andy (KU4XR), Markus (DF6NM) and John (F5VLF).

I agree the first letter looks like 'F'. I don't think the timings are quite right for your TX Markus, although the frequency is. The 'bursts' of signal lasted about 2min 10sec each. So still an unknown really. No trace of the same signal last evening. Will look again tonight.

Thanks and 73.

Chris, G4AYT, Whitstable, Kent, UK.