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Re: L-Band Sanity - was "being heard over LEILA siren"



One thing, Tony, is that L-band antenna gains are higher than U-band.  So 
the sat is quite a bit more sensitive...that takes some of the 10dB 
pathloss hit away.
My link budget calcs show excess uplink at the given conditions up to 17 
degrees squint at apogee...and obviously also at even higher squints/lower 
ranges.

At 14:21 2003-08-22, Anthony Monteiro wrote:
>Dear Friends,
>
>As suggested by Emily, let's look at some numbers:
>
>
>1. A 1.8m (6') dish has around 27 dB gain at 1269MHz
>
>2. Let's assume around 2 dB for the cable loss
>    (i.e. 70' of LMR-600 has about 2.1 dB loss)
>
>3. A 5 watt transmitter into this antenna system
>    puts out a little over 1.5 kilowatts EIRP.
>
>This might sound like a lot but...
>
>*** the path loss at 1269 is 10dB greater than at 435 MHz ***
>
>So this is like running 150 watts EIRP on U-band which is
>in the right ballpark and is more than 10 dB below the beacon
>at 60,000 Km.
>
>The exact levels will depend upon a number of factors such
>as the actual cable loss, the dish efficiency, the distance
>and squint from AO-40 etc.
>
>Ok, now an opinion; I think you could easily hear this station
>over the LEILA siren since there is no notch. You can often hear
>U-band stations over LEILA as well even with the notch.
>
>Comments are welcome!
>
>73,
>
>Tony AA2TX
>
>---
>
>
>At 01:22 PM 8/22/03 -0700, Emily Clarke wrote:
>
>
>>Oh please yes!  :-)
>>
>>Seriously I wouldn't want to have a war break out but a good discussion 
>>would be nice.  I just started working on AO-40 and hearing some good 
>>pros and cons would be helpful.
>>
>>73
>>
>>Emily
>
>----
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Scott Townley NX7U
Gilbert, AZ  DM43di
http://members.cox.net/nx7u

----
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