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Old May 3rd 06, 03:32 PM posted to rec.radio.amateur.antenna
Robert Lay (W9DMK)
 
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Default spectral power density

On 2 May 2006 01:09:53 -0700, "electro"
wrote:

in other words, when i have a transmit modulation bandwith of 500kbps
my peak power level must be 8 dBm...right?


No - that is not correct, in my opinion. My interpretation is that the
spectral power density in a 500 Hz bandwidth must not exceed the limit
of 2 milliwatts per Hz. (Simply spread the 1 watt over a width of 500
Hz.
In my original post I thought your message said 500Hz. Now I see you
are saying 500kHz. Which is correct?

what if i use 6khz or
5khz?does proportionality hold here or just say in any bandwith not
greater than 500khz, the peak power level should not always exceed
8dBm?..


The 8 dBm is a red-herring. I took your value of 8 dB as Gospel. If
someone says 8 dB they don't mean 8 dBm and vice versa.

Can you make sure of the accuracy of your excerpts, because I see
nothing in the Part 15 regs that correlate with your numbers.

In other words, I'm working with nothing but your excerpts and common
sense electrical engineering.