[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Filter for V/U U/v seperation, FYI




Hi Bill,

I think you have something hooked up incorrectly.  The insertion loss for 
the Diamond MX-72 is less than .8 db  I don't have the specifications on 
the Comet, but it is probably similar.  So the numbers don't add up and I'm 
not experiencing anything like it.

I have the input to the MX-72 connected to my antenna, and the 70cm 
connected to my preamp.  The 2m side of the MX-72 is connected to a 50 ohm 
load.  The design is that the energy comes from the antenna into the 
duplexer, and gets split into a 70cm component and a 2m component.  The 2m 
component is routed to the 50 ohm load.  The 70cm side goes into the preamp.

It sounds to me as if you have the duplexer hooked up wrong because you 
should not be seeing anywhere that much suppression on the 70cm side if it 
is hooked up correctly.

73,

Emily



At 03:10 PM 7/9/2004 -0400, you wrote:
>I tried two duplexers to try to eliminate my 2m interfering with 70cm. I
>tested 70cm receive first with a local repeater without duplexers in line
>S9+ signal. Tested same repeater with Diamond MX-72H in line before the mast
>mounted preamp, signal strength S3, Tested with Comet CF-4160 same place
>and did not get any reading on the s meter. They both reduced or eliminated
>the interfering 2m signal, but apparently my 70cm as well. Now looking at a
>dci bandpass filter with approx   .25db insertion loss.
>Bill
>
>
>
>
>" A few weeks ago there was some discussion on the bb about
>   desense between 2M and 440cm side of things.  A Comet Duplexor
>   was suggested as well as some commerical filters. "
>
>----
>Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
>Not an AMSAT member? Join now to support the amateur satellite program!
>To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



---------------------------------
W0EEC - CM87tm
AMSAT Area Coordinator - San Francisco Bay Area
http://www.projectoscar.net    http://www.PlanetEmily.com 
http://www.experthams.net/ao7

Help Launch Echo - http://www.amsat.org/amsat/sats/echo/index.html
---------------------------------  

----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home