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N-connector loss



Please look at page 2 of this file at the Amphenol web site:

http://www.amphenolrf.com/pdf/type_n_spec.pdf

They spec the loss as 0.15 dB loss at 10 GHz. I doubt that amphenol is going
to publish incorrect specs. Those specs are consistent with my measurements.

Pieter Ibelings


----- Original Message -----
From: "Pieter Ibelings" <elpieter@hotmail.com>
To: "guy lemke" <guy@com-pair.net>; <amsat-bb@AMSAT.Org>
Sent: Sunday, May 20, 2001 14:29
Subject: Re: [amsat-bb] S-band receiving requirements


> Hi Guy,
>
> You can get as defensive as you want, but maybe you should not be buying
> those crummy connectors. I deal with N connectors every day and I don't
rely
> on what others say. I do all the measurements myself. I have the latest
> model HP8753ES 3 GHz network analyzer on my bench and I have never seen
> losses that high. If you are getting 0.5 dB, your connectors can be rated
as
> "radioshack" quality.
>
> Pieter Ibelings
>  N4IP
>
>
>
> ----- Original Message -----
> From: "guy lemke" <guy@com-pair.net>
> To: "Pieter Ibelings" <elpieter@hotmail.com>; <amsat-bb@AMSAT.Org>
> Sent: Sunday, May 20, 2001 14:12
> Subject: Re: [amsat-bb] S-band receiving requirements
>
>
> > I don't think so!!! I work with 2.4 Ghz every day at the company I work
> for and
> > we use times microwave and I have talked to their engineers many times
and
> they
> > have told us that this is what we should expect... So believe what you
> would
> > like but this is still my answer to the question.
> >
> >         Guy Lemke
> >         KD6MTU
> >
> > Pieter Ibelings wrote:
> >
> > > 0.5 dB per N connector? Sounds like too much! I have measured a pair
of
> BNcs
> > > and a pair of N connectors all in a line at 1.5 GHz and I get less
than
> 0.5
> > > dB. I doubt that a single one is 0.5 dB. Maybe if you buy the
radioshack
> > > versions.
> > >
> > > Pieter
> > >
> > > ----- Original Message -----
> > > From: "guy lemke" <guy@com-pair.net>
> > > To: "Jerry Pixton" <jpixton@shentel.net>; <amsat-bb@AMSAT.Org>
> > > Sent: Sunday, May 20, 2001 13:48
> > > Subject: Re: [amsat-bb] S-band receiving requirements
> > >
> > > > You should figure in .5 Db per N connector if they are of good
quality
> !!!
> > > >
> > > > Jerry Pixton wrote:
> > > >
> > > > > Mike and Gene,
> > > > >
> > > > > Ya, that coax ahead of the preamp/downconverer is all important.
> What is
> > > > > the loss at 2400 Mhz of just a male/male N connector between the
> antenna
> > > > > and converter  I have been using 0.25 db as a wag.
> > > > >
> > > > > If I have a helix antenna with 17 dBic, does that mean I should
> enter 14
> > > > > into the spread sheet to cover the loss from circular to linear.
Or
> > > should
> > > > > I be entering 20 since my antenna is really 3 db better than a
> linearly
> > > > > polarized antenna?????  The antenna gain seems to be used on the
> data
> > > sheet
> > > > > to compute the transponder levels. Is the 3 db polarity loss
> embedded in
> > > > > the "24" factor at the end of the equation?
> > > > >
> > > > > Jerry W6IHG
> > > > >
> > > > > At 08:17 AM 5/19/01 -0400, Mike73@aol.com wrote:
> > > > > >In a message dated 5/18/01 8:40:08 PM Eastern Daylight Time,
> > > > > >al7eb@ptialaska.net writes:
> > > > > >
> > > > > > >  Gene Marcus' spreadsheet is very useful for this process.
> > > > > >
> > > > > >I agree!!  A couple of pointers.....
> > > > > >
> > > > > >The very first coax loss number before the preamp is very
> important.
> > > This
> > > > > >really effects overall system noise. I calculated the 3 foot
jumper
> > > (RG-8) on
> > > > > >my Meyers dish as -.36 dB at 2400 (yuk). Throw that number in the
> > > spreadsheet
> > > > > >and see what happens.
> > > > > >
> > > > > >Also, I asked Gene about the antenna gain. The number you input
is
> dBi
> > > > > >Linear. So to be accurate, if you're using a Meyers dish you
should
> > > subtract
> > > > > >3 dB for the theoretical loss when going from linear to circular.
> So,
> > > for a
> > > > > >Meyers dish that was advertised as 25 dBi, you would input 22
dBi.
> > > > > >
> > > > > >I can see if I were to do any improvements to my system, I'd
> probably
> > > attack
> > > > > >the antenna. I already have a good low NF preamp. The changes I'd
> > > contemplate
> > > > > >would be to change the feed to circular and reduce the coax loss
> before
> > > the
> > > > > >preamp. To see the effect of these two changes, input .1 dB for
> first
> > > coax
> > > > > >loss and 25 dBi antenna gain in the spreadsheet and you'll see
the
> > > > > >improvement.
> > > > > >
> > > > > >Now back to cobbling together a 5668 uplink :-}
> > > > > >
> > > > > >73,
> > > > > >Mike, N1JEZ
> > > > > >AMSAT #29649
> > > > > >Local Area Coordinator
> > > > > >"A closed mouth gathers no feet."
> > > > > >----
> > > > > >Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> > > > > >To unsubscribe, send "unsubscribe amsat-bb" to
Majordomo@amsat.org
> > > > >
> > > > > ------------------------------------------
> > > > > Dr. Jerry R. Pixton, PIXOS Designs LLC
> > > > > http://www.pixos.com/designs/
> > > > > jpixton@shentel.net
> > > > > ------------------------------------------
> > > > >
> > > > > ----
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> > > > > To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
> > > >
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> > > >
> >
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> >
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>

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