[MLB-WIRELESS] request

[evilbunny]

Hello paul,

Noise has nothing to do with surrounding freq's noise has everything
to do with transmission on the same freq... why do you think microwave
ovens and 2.4Ghz phones are bad for wifi?

I will prolly balls this up and explain it badly, but interference
occurs when two opposing wave forms of same freq nullify each other
out, or 1 blasts the other away...

Why do you think people use solid dishes for antenna, maximum
reflectivity of signal, the radio and/or driven element discriminate,
not the reflector...

(insert part about amp's not discriminating and amplifying noise as
well :P)

-- 
Best regards,
 evilbunny                            mailto:evilbunny at sydneywireless.com

He's a few strings short of a guitar.

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Tuesday, December 24, 2002, 9:54:23 AM, you wrote:

pvdb> OK, that is fine, but if you want it to be efficient...???

pvdb> I always thought the point was to reflect (interact with) the majority of the 
pvdb> incoming polarised signal while allowing other smaller frequencies to pass 
pvdb> (through the gaps) and larger frequencies to miss the antenna. By that 
pvdb> rational, the smaller the gaps the more noise you should have due to less 
pvdb> efficient antenna filtering.  similarly, the larger the antenna, the more 
pvdb> signal you will collect, but the more resonance frequencies you will collect 
pvdb> (lambda = N times the peak resonance frequency of the gaps).  However, this 
pvdb> is offset by the greater collecting power (= better concentration of signal 
pvdb> by directional discrimination).

pvdb> so the antenna is a resonator that also acts as an amplifier and band pass 
pvdb> filter...


pvdb> On Mon, 23 Dec 2002 05:40 pm, you wrote:
>> Hello paul,
>>
>> pvdb> Iv'e been meaning to ask... could someone with one of these measure
>> the wire pvdb> thickness and gaps?  I can do the parabola bit, it's the
>> spacign for pvdb> filtering that I don't know....
>>
>> Isn't it just smaller then 1/4 wave?
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