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Date: Sun, 09 Mar 2014 00:47:48 +0100
From: Tobias DG3LV <DG3LV@gmx.net>
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Subject: Re: LF: Microphone via WLAN (WiFi) ?
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Hi Stefan  !

10 mA at 5 Volts will not be enough. You may get analog(!) audio 
transmission sets for 2G4 or 5G8, but they do not use WLAN.

As Wolf has stated, there will be a lot of software involved in all of 
such a system you want to use.

Maybe this could work w/o software development:

Transmitter site using a RaspberryPi equipped with ext. Soundcard and 
WLAN. Software "VLC"/Linux for "audio streaming"(Server).
Receiver site using standard (WLAN-)Windows PC and software 
"VLC"/Windows for streaming client.

Setup both VLC's to uncompressed audio. That should deliver 16 Bit 
Stereo audio (max. 96dB SNR) at 44.1 or 48 kS/sec.

A RaspberryPi consumes abt. 3 Watt + soundcard + WLAN. Would that fit 
your requirements ?

73 de dg3lv tobias

Am 08.03.2014 15:08, schrieb Stefan Schäfer:
> Hi all,
>
> Again i spent some time to find a module which allows to transfer a
> mircophone input signal via WLAN to the PC. Without success...
>
> To make things clear:
>
> The system has to consist of to parts:
>
> 1: The first one is battery supplied and has a microphone input (like a
> cheap external USB soundcard) and a WLAN output, using an external
> antenna and SMA plug. I.e.: Input: 3.5mm microphone jack. Output: SMA
> WLAN antenna connector.
> 2: The second part is connected to the PC and is a WLAN receiver that
> appears as a normal external USB soundcard and allows to receive the
> audio signal from the first part of the system.
>
> The system allows to run a /p receiver for VLF or any other band.
>
>
> An expert could create such a circuit for himselfe but i need to buy
> something like that, if it is available. But all i can find in the web
> is the opposite way, i.e. people who want to transfer their sound from
> the PC to a /p loudspeaker or headphone, argh...  Or, a big device which
> includes a real big microphone (dynamic range ???). These are expensive
> systems.
>
> However, external soundcards are cheap and WLAN modules are cheap too.
>
> So, isn't there such a device for a few EUR in the web, these days? It
> has to have a dynamic range of  at least 100 dB, like the 2 EUR external
> soundcards at amazon do (with some luck).
>
> Any help is much apprechiated :-)
>
> 73, Stefan/DK7FC
>
>