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Re: No VP6 tonight?

Hi Bill,

on 3/11/03 6:47 AM, Bill Booth at 710138@ican.net wrote:

> Well I was one of those guys last nite that got a bit too close to the
> beacon.....or so I was politely told.  I have not been on the bird that long
> so maybe some education is in order.

Hey, at least you are willing to learn.  Making a mistake like this is not
inexcusable if you just don't know.
> How far away from the beacon is the suggested norm. ??
I think you want to stay at least 10 KCs away from the beacon on either side
- especially for SSB.  I forget the exact spacing, but listen to what most
other stations are doing.  Additionally, the control team has asked that
during the K band window that those people using the S band downlink move
even farther away from the beacon so that we are outside of the K band
downlink.  That leaves K band downlink clear for the guys who want to use

> Because of the doppler effect the beacon will move closer to you if you are
> just outside the beacon.  Since it is the practise to move recieve
> frequency, eventually you are on the beacon.  So in the end you have to move
> off your orginal frequency and go elsewhere.....which means you should start
> at the top end of the band (where no one ever is) and work down (which no
> one does).  This means you should start out at the suggested norm plus
> doppler and leave that space as dead band. ??-
Well, there's a couple ways to approach this.  If you have computer control
of the rig and you use the "one true rule" approach, you will be adjusting
both up and downlink frequencies.  But it take both stations having this

But if you just tune your downlink, then yes, you will drift.  But that's
expected.  Remember, the beacon will move somewhat as well due to doppler.
But if you stay far enough above the beacon starting out, then you won't
need to worry about it.  The AO-40 passband is just huge.  It's terribly
underutilized, so there's no need to crowd the beacon.

Finally, since you are new to the bird, you may also not realize that the
control team has asked that all stations keep their downlink to a level of
10 dB below the beacon.  I was never active on AO-13 but I guess you only
needed to be 3 dB or so below the beacon there.  Because of the problems
that AO-40 has, it's a different animal.  There's a lot of really loud
stations, particularly those running L band, but that doesn't make it right.
Loud signals on the U band uplink cause the AGC to go up hard and it makes
it more difficult for everyone.

Last night, I heard more stations that were nearly as strong as the beacon
than I heard stations at the proper level.
> Like I said I have an open mind and am willing to learn.

That's a great way to look at things!

Welcome to AO-40.



Jon Ogden
NA9D (ex: KE9NA)

Citizen of the People's Democratic Republik of Illinois

Life Member: ARRL, NRA
Member:  AMSAT, DXCC

http://www.qsl.net/na9d   <- Updated on 1/22/03!!!

"A life lived in fear is a life half lived."

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