[Moon-net] Fw: How much gain and where should it be?

[Edward Cole]

I have a eme path-link calculator (excel spreadsheet) for VHF that 
includes NF calc for 3 cascaded stages available on my 2m eme webpage:
http://www.kl7uw.com/eme144.htm

There is a mw eme calculator on the OVRO page:
http://www.kl7uw.com/emeOVROcalc.htm

73 Ed - KL7UW

At 01:22 PM 11/27/2007, Bodo Heyl wrote:

>  Dear Dave,
>
>  additional to the reply of Lance, W7GJ, a further hint:
>
>  There is the excellent software from VK3UM (download @ SM2CEW)
>called EME-calculator. You can just insert your datas (attenuation
>of cable, antenna noise, sky noise etc.)as result you will see your system
>sensitivity, its a real eye-opener..
>
>
>  73s de Bodo/DL2FCN
>
>
> > ----- Original Message -----
> > From: "Dave Anderson, K4SV" <davek4sv at yahoo.com>
> > To: "EME Reflector" <moon-net at list-serv.davidv.net>
> > Sent: Tuesday, November 27, 2007 8:20 PM
> > Subject: [Moon-net] How much gain and where should it be?
> >
> >
> >> Hi Gang,
> >>
> >> Since I am new to EME I have lots of questions.
> >>
> >> I would like to know How much gain to have, and, Where should the gain
> >> be,
> >> at the antenna or at the rig?
> >>
> >> I have a very nice M2 H frame with 4 2MXP20's.  It sits atop a 32 foot
> >> (10
> >> meter) tower with clear visibility of the sky and I live on top of a
> >> hill.
> >> It's feed with Andrew 7/8 Heliax with a few relatively short FSJ4
> >> Superflex jumpers to connect all the pieces.  I am currently using a Icom
> >> 910H radio, 8877 Amp and preamp located in the shack.  I get excellent
> >> reports on transmit.
> >>
> >> The run of 7/8 Heliax and FSJ4 is no more than 85 feet when you add it
> >> all
> >> up.  All connectors are Andrew.
> >>
> >> So my first question is
> >> Where should I put the 0.3 NF Preamp and its Bandpass filter?  At this
> >> time I have a single feed line with Polarity switching at the antenna.
> >> The obvious answer is at the antenna, but, does it really make that much
> >> difference considering my low loss?  Putting the Preamp at the antenna
> >> requires antenna switching which induces more loss. In the shack the
> >> preamp connects easily to the amp relays.  So should it be in the shack
> >> or
> >> at the antenna?
> >>
> >> So how much gain is needed and/or required for maximum performance?  Is
> >> there an optimum gain or convenient gain?
> >>
> >> If someone has played with a similar system layout or has completed tests
> >> with the preamps I would like to hear your test results.
> >>
> >> Thanks in advance for all the replys.  I promise to share the results
> >> from
> >> my questions.
> >>
> >> 73's
> >>
> >> Dave Anderson, K4SV
> >> Tryon, NC
> >> 828 777-5088
> >>
> >> www.K4SV.com
> >>
> >> _______________________________________________
> >> Moon-Net posting and subscription instructions are at
> >> http://www.nlsa.com/nets/moon-net-help.html
> >
>
>
>_______________________________________________
>Moon-Net posting and subscription instructions are at 
>http://www.nlsa.com/nets/moon-net-help.html

73,
Ed - KL7UW
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