Re: VLF: Back on 5.17 kHz / 58 km...

[Paul Nicholson <vlf0403@abelian.org>]

> With your given RAM, how many characters can you decode in 16K25A?

20 chars uses 42Gbyte RAM.

25 chars is about the limit on my workstation unless I turn off
a few things.  But more is no problem, I simply spot request
a suitable machine on AWS.  The largest available has 1952
Gbyte RAM and 128 cores, I'm just waiting for an excuse to
give that one a try!!  950 chars would use all that RAM but
the sender program wont do such a large block.

> And how long does the decode process take then?

Only a few minutes (lots of cores) because messages usually
decode quite early in the phase search.

> The carrier on 5170.001250 Hz is still on the air and will
> run until 18 UTC.

Thanks that will be useful.

I'm glad you've discovered the signal calculator, takes out
some of the guesswork.  Your chosen settings look good.

4270 will be interesting.  These various bands on VLF are
about as different from one another as the HF bands are!

Still don't know why 2970 isn't working.  My ERP calculations
are more pessimistic than yours but still predict enough ERP
to detect here.

Jacek's timing system (vlfrx-tools) is working very well.

Meanwhile, I'm working on an interesting enhancement to
EbNaut...

--
Paul Nicholson
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