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RE: L on AO40



Perhaps I put my foot in my mouth. However looking into things
a bit more deeply it seems to be a case where there is a difference
between theory and practice. I generally am one who tries to play by
the rules as it is to everyones benifit.
The beacon is usually about S7 on my FT-736 and
FT-847. No signal noise about S1 or less.  The majority
of  QSO's are about S5 to S6. At this level they do not
trigger Leila  At 3db per S unit that is 3 to 6db below the beacon. 
Following the 10db rule most signals are thus 4 to 7db too strong. 
I have a 1.2 meter dish and DEM preamp and convertor and from
operating experience know that I can hear as good or better than
most. I would say that half or more of the operators on AO-40 who 
are using lower gain ants would have difficulty operating at uplink 
levels of 10db below the beacon. With QSB and AGC action signals 
of this level would often drop into their noise level.
My mode L comes back S4 to S5 which is as I say less than the average. 
As the pointing angle increases above 10 degrees my signal drops even 
more and that is when more power would produce a signal that most 
operators can copy.  On many occasions I have switched to U uplink as 
the operator I was in QSO with was having trouble copying me. The
extra S unit or 3db made the difference.

Clare VE3NPC




>L Clare Fowler wrote:
>
>> I have an array of four times 27 turn helix ants with a
>> 70cm four way power divider.(1:1 SWR on third harmonic)
>> Theoretical gain 25db. Probably several db less.
>> Feed line 30 ft hardline and 10 feet RG8.
>> Using FT-736R barefoot with 10 watts.
>> Have had many solid QSO's with it.  However signal
>> is about 6db below beacon. Really need another
>> 10 watts to hit bird at max allowable level.
>
>Clare,
>    If you are 6dB below the beacon now, you don't need any more power
>since you are already several dB stronger than the max allowable level.
>Remember that unlike most of the other satellites, max user signal should
>be 10dB below the beacon.
>
>73
>-----------------------
>Jim Walls - K6CCC
>k6ccc@amsat.org
>http://home.earthlink.net/~k6ccc/
>626-302-8515    FAX  626-302-7501
>AMSAT member 32537 / WSWSS member 395
>
>
>




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