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Hello Pete and others.
I would be gratefull (and probably many
others) if someone could write some very simple one liners on what is
required and how to use a sound card for a 9kHz RX. Don't need pages of
computer gobbledegook, just the KISS system 'Keep It Simple Stupid', with no
disrespect to others.
The 9kHz dc rx is coming on well and will soon be
operational, time permitting.
73s
Ken M0KHW
----- Original Message -----
Sent: Thursday, March 04, 2010 10:51
PM
Subject: Re: LF: 9kHz: soundcard RX
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If I have understood the issue, it is that you are saying
sound cards are very venerable to damage when fed with an external
antenna to the mic socket?
If that is the assertion then I am say that I have had a good
survival rate when doing just that over a relatively long period of
time. Also other pieces of kit are connected to antennas like very
very expensive transceivers and modems connected to antenna like
telephone wires... there is potential hazard to all these devices. So we
do take a risk when connecting any sensitive electronic device to an
external antenna but the risk can be mitigated by ensuring the antenna
is removed when not in use and especially during lightning storms and /
or by adding some form of static bypass arrangement. And yes a pair of
back to back diodes appear to prevent damage because of their
voltage limiting characteristic. It is a precaution I would
recommend as a minimum protection but you can never be sure how well
they would actually work. Its a risking business play with high external
antennas but that's what we do.
That is my point and nothing else. 73 es
GL petefmt --- On Thu, 4/3/10, Chris
<[email protected]> wrote:
From:
Chris <[email protected]>
Subject: Re: LF: 9kHz:
soundcard RX
To: [email protected]
Date: Thursday, 4
March, 2010, 16:25
Not sure what your point is, surely
you're just saying the diodes are doing their job?
Chris, G4AYT.
----- Original Message -----
Sent: Thursday, March 04, 2010
7:07 AM
Subject: Re: LF: 9kHz:
soundcard RX
never blown a sound card up yet in over almost
ten years of use. Two back to back diodes on the antenna lead
close to the input plug. Don't leave it connected during
thunderstorms. Most modems are left connected day and night to
very very long over head telephone wires for years with out
problems. Vastly over hyped problem.
73 es GL
petefmt
--- On Wed, 3/3/10, Horst Stöcker
<[email protected]> wrote:
From:
Horst Stöcker <[email protected]>
Subject: LF:
9kHz: soundcard RX
To:
[email protected]
Date: Wednesday, 3 March,
2010, 9:32
>And what about a simple band pass
filter to supress the 50Hz and it's harmonics? Necessary or
dispensable? You can hear (!) the difference. I just
took a 10mH coil from Reichelt to improve my soundcard-RX
before one of the last SAQ activities. Despite of
more or less excellent digital filtering of SpecLab it's a
good idea. One should not keep the soundcard busy with
unwanted signals. What I am not sure about is the use
of an audio transformer. It might have some influence to the
signal. As it just has to keep the soundcard from beeing
blown it might be a good idea to take a cheap soundcard
instead of the audio transformer - and maybe a second in
spare. Stefan, what USB-soundcard you bought for 10
EUR ? Horst
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