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Posted by Smarty on 02/19/07 06:57
Martin,
I became a true believer in the magic of proper shielding after using a
remarkably sensitive HF receiver built on a PCI card, stuffed into a Dell
low-budget desktop machine. See:
http://www.shortwavestore.com/sws/product.php?productid=582&cat=0&page=1
How you can hear weak microvolt signals when this board is sitting in
switched 5 and 12 volt bus noise from DC to nearly a GHz (800 MHz bus)
defies belief IMHO. But yet it works and works well.
Stacked 30 element yagis and 25 dB preamp would hear all sorts of stuff, but
then again, the front to back ratio / beamwidth of the array as well as the
elevation beamwidth would give you tens of dB of spatial rejection.
Smarty
"Martin Heffels" <goofie@flikken.net> wrote in message
news:nehit25lo0sq9cdvh2fq9u2ugnfq00oq4g@4ax.com...
> On Mon, 19 Feb 2007 01:19:29 -0500, "Smarty" <nobody@nobody.com> wrote:
>
>>Well Martin, I will have to assume you are joking. Even though 432 MHz
>>does
>>lie within the UHF spectrum which (we) hams utilize, the amount of
>>radiated
>>EMI coming from a Sony sensor being strobed at this frequency would be way
>>below the atmospheric / Boltzman noise a very short distance from the
>>camera.
>
> I was joking of course :-) We have to assume that Sony will provide proper
> shielding as well, to reduce the RFi output of the camera. But obviously
> it
> would only be a concern at a contest when you try and shoot some stuff
> around 4 stacked 30 element 70cm yagi's with 25dB pre-amp. Something like
> that :-))
>
> -m-
> --
> Official website "Jonah's Quid" http://www.jonahsquids.co.uk
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