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

Re: One Coax Feedline.



Pat,
I agree with Jon's comments, but really suggest you think this through.  Even 2 inexpensive duplexers, like the MFJ units, are $30 each.  For $60 you can buy 100 feet of 9913F and avoid all the problems noted below.
73,
Jerry, K5OE
ps:  the duplexers do provide a significant amount of filtering.  I use one of the MFJ units ahead of my 70 cm preamp (just use the 70 cm side) and it completely eliminates the 2 m de-sense problem; a pretty good tradeoff for a slight amount of S/N degredation.

<< on 8/23/00 6:19 PM, Pat McGrath at pat_mcgrath@yahoo.com wrote:

> I would like to use one length of coax to connect a 2m and a 70cm antenna to
> a ICOM 821 transceiver.

Curious why you want to do this.

> 
> Do I use two duplexer? One at the antennas and the other at the
> transeceiver?

That's sure one way to do it.

> 
> Would I need a 2m and a 70cm DCI filter at the transceiver?

Well, duplexers are filters.  So you'd probably get enough filtering action
from that.  They do have loss though and sometimes significant depending on
whose you use.

> 
> Are DC passthrough  DCI filters and duplexers available to power the mast
> mounted preamps?

Oh boy....probably not.  Most (but not all) filters are DC shorts.  I don't
remember what the DCIs look like.  Why not run separate DC feeds.  You'll
need to run control lines anyway to turn the preamps on and off unless you
have auto sensing units.

73,

Jon
NA9D


-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)

Member:  ARRL, AMSAT, DXCC, NRA

http://www.qsl.net/ke9na

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

----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
 >>


----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home