LF: GBR Info - Thanks !

[DL4YHF@aol.com]

Hi Alan, Andy, John  and the group,

Thanks for the quick response to my question about the 16kHz-signal.

I must have missed the information formerly posted about MSK on 16kHz on this 
reflector, but now I got the picture ;-). As the signal is MSK, it is a 
special kind of FSK (modulation index 0.5) but also a special kind of PSK, 
and it once was RTTY some time ago.

Also ok on the 'temporary mode switch' from MSK to CW on Tuesday afternoon. 
For those who don't have the posting, here it comes again (originally relayed 
by G3XDV from G4KHU):
> "Listeners may be aware that the UK Royal Navy are celebrating the
> Centenary of the Royal Navy Submarine service with a gathering of UK and
> overseas submarines in the Clyde. This year is also the 75th anniversary
> of operation of the GBR transmitter (Rugby). 
> As part of this celebration 'It is hoped' that a special A1A Morse code
> transmission from the GBR long wave transmitter will be made.
> For those with an interest in VLF reception please listen to 16kHz (yes 16
> not 60kHz!) on Tuesday 29th May 2001 at 1200GMT and 1345GMT."

--

To John G4CNN, asking about PC-based reception below 10kHz:

Hmm.. well.. the system does receive below 10kHz but I don't know how good. I 
don't have a commercial receiver which goes below 10kHz, so I cannot compare 
my RX system to  a professional RX. I don't even know a (reliable) signal 
between 1 and 10kHz to listen for. The RX antenna is a heavy bundle of 19 
ferrite rods, insulated from each other to avoid currents in the 
semiconducting material, and 400 turns of wire. Total inductivity about 30 
millihenry, parallel caps for resonance between 15..20kHz and a high-current 
JFET as impedance converter (no voltage gain required for the MIC input of 
the PC). With more C's shunted it will work on even lower frequencies, but 
not very good I suppose.


73, Wolf, DL4YHF.