Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: VLF: EbNaut transmissions on lower frequencies?, pre-tests: 6.47kHz

To: [email protected]
Subject: Re: VLF: EbNaut transmissions on lower frequencies?, pre-tests: 6.47kHz
From: DK7FC <[email protected]>
Date: Sun, 15 May 2016 19:08:51 +0200
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <[email protected]> <279E0DEFDAFA4C849152DBBA3BFEDE8C@White> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
User-agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3
Hello Paul,

Excellent! I'm happy :-)
The error map correlates with the QRN strength, see https://dl.dropboxusercontent.com/u/19882028/VLF/wald5.jpg
It's almost June and it works anyway...

The antenna current was quite stable at 220 mA. I'm planning to rise it up to 240 mA and will run the very long message (19 chars) again. For 240 mA i need to be quite close to the resonance, so i need the transductor circuit to hold the resonance automatically. If some rain starts to fall, the total C will rise a bit, then the DC current in the transductor coil will rise, the transductor L will fall and the resonance will be hold on the spot!

So far we got 3 chars, 5 chars and now 6 chars on 6470 Hz, each one at 100s symbols.

73, Stefan

Am 15.05.2016 18:50, schrieb Paul Nicholson:
Stefan wrote:

> f = 6470.00000 Hz
> Start time: 14.05.2016   21:40:02 UTC
> Symbol length: 100 s
> Characters: 6
> CRC 16
> Coding 8K19A

An easy decode of 'JN49IK' with Eb/N0 = +3.8 dB.

Phase pattern: 30   30    0    0

Carrier S/N: 16.96 dB in 17.9 uHz

Symbol errors: http://abelian.org/vlf/tmp/160514a.gif

>  the same message

Now I know the message I can reverse the modulation of
the previous attempt to see why it didn't decode.

--
Paul Nicholson
--


<Prev in Thread] Current Thread [Next in Thread>