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Phased Beverages! (was: EVE vs Beverage?) (fwd)

Subject: Phased Beverages! (was: EVE vs Beverage?) (fwd)
From: JPontek@aol.com (JPontek@aol.com)
Date: Fri Aug 18 01:36:10 1995
Brett,

Thank you for the input! Hee Hee, I have no cows, err, yet,..., but I have
venison, so I need 6 feet clearance. I believe the antenna wire will keep
will give me stabile in one direction, but I am considering drop down legs
from the verticle post for stability on the other plan (path traveled by the
deer).

Yes, I remember my 6 & 2 meter beam moving about the roof in Wash., D.C., in
the mid 60's from a rain & wind wash, or two. I did n't mind, except it
screwed up the beam headings!

This will be my 1st year, I hope, with Beverage antennas for the low noise
choice.

I am now working on matching networks and preamplifiers.

73, K8Joe"Palooka"
jpontek@aol.com


>From Bob.Wendling@698.gigo.com (Bob Wendling)  Fri Aug 18 01:26:59 1995
From: Bob.Wendling@698.gigo.com (Bob Wendling) (Bob Wendling)
Subject: no mail
Message-ID: <a2f_9508172319@gigo.com>


NO MAIL
--
: Fidonet:  Bob Wendling 1:203/698  .. speaking for only myself.
: Internet: Bob.Wendling@698.gigo.com

>From Marijan Miletic <s56a@ljutcp.hamradio.si>  Fri Aug 18 08:36:29 1995
From: Marijan Miletic <s56a@ljutcp.hamradio.si> (Marijan Miletic)
Subject: DSP power
Message-ID: <73569@ljutcp.hamradio.si>

AA4LR wrote the following regarding DSP:
                                                                                
>The problem with putting a DSP in the IF of a receiver has to do with
>sampling rates. An affordable DSP has a limited processing power, so the IF
>frequency must be reasonably low (10-100 KHz). Higher frequencies reduce
>imaging problems, but require faster digitizers and more DSP processing
>power. Lower frequencies need less expensive digitization and DSP
>processing power, but limit the useful receiver bandwidth of the DSP and

DSP power is NOT related to the carrier frequency in the practical cases of
band-limited signals.  The same power is needed for 9 kHz sampling of audio
signal or 455 kHz IF if the input signals are within 4.5 kHz passband.
A/D converter is the only limiting factor so TS-870 11 kHz 4th IF fits
nicely with CD digitizers with 20 bits resolution.

DSP is well entrenched in commercial rigs from Collins, Watkins & Johnson,
Rohde & Schwarz so there is NO need to repeat some early mistakes as it is
all software.  Or shall we have FT-101, VHS, MS-DOS etc. story again?

73 de Mario, S56A, N1YU.

P.S.  How many filter taps one needs for >100 dB rejection of decent
analog filter?  Is the time delay acceptable in real life?

>From kiddi@marel.is (Kristinn Andersen)  Fri Aug 18 11:39:10 1995
From: kiddi@marel.is (Kristinn Andersen) (Kristinn Andersen)
Subject: Need centered world map
Message-ID: <9508181052.AA29908@marel.is>

I need one of those maps that has my QTH in the center and shows propagation
directions as straight lines - the one where Australia ends up encircling
the earth and beyond that you fall off into the black hole!!  Sorry, but I
don´t recall what the proper term is (...centric something?).

Anyway, I know there are some programs around that can custom print this.  I
would like to copy such a program through the internet or, if someone can
make me a map, I would like to copy it through the net.  This would do in
the short term.  In the long term, if someone knows who sells such software,
please let me know.

My location is just south of Reykjavik, Iceland.  Lat: 64N, Long: 22W
(approximately).

Thanks and 73 de Kristinn, TF3KX (kiddi@marel.is)


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