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

Re: Elk Antennas for HTs?



I have an FT-530 HT and have used it for several years.  It is FULL DUPLEX. 
It works very well for satellite use.

73,

Woody
KJ4SO
AMSAT  # 5562

----- Original Message ----- 
From: "Emily Clarke" <w0eec@AMSAT.Org>
To: "Doug McLaren" <dougmc@frenzy.com>
Cc: "AMSAT BBS" <amsat-bb@AMSAT.Org>
Sent: Wednesday, October 20, 2004 1:08 PM
Subject: Re: [amsat-bb] Elk Antennas for HTs?


> The fact that the two antennas in the Arrow have two connectors is not 
> because they are 90 degrees out of phase and not the reason for the 
> duplexer.  You could easily use a standard BNC "T" connector and match the 
> antennas impedance, which would accomplish the same as the Elk.  The 
> primary use of the duplexer is isolation.
>
> The original statement was about the IC-W32A which I own (I do not own the 
> other radios you mention) so I can't speak for their built in duplexers. 
> However I don't believe the FT-530 is full duplex.  I seem to recall it 
> turns off the second receiver whenever you transmit which is not the same 
> as FULL duplex.  However since I don't own the radio don't quote me on 
> that.
>
> My experience with the Elk and the W32A in FULL duplex mode is that it 
> desenses the receiver when you are transmitting so you cannot hear 
> yourself coming back down on the downlink frequency.  I have tried the BNC 
> T connector method mentioned above rather than the duplexer with the Arrow 
> and it desenses, though not as bad as the Elk did since the 90 degree 
> difference in transmit and receive antennas offers a little isolation. 
> With a duplexer you get additional isolation and it doesn't desense.
>
> 73,
>
> Emily
>
>
>
> At 11:24 AM 10/20/2004 -0500, you wrote:
>>On Tue, Oct 19, 2004 at 10:37:06AM -0700, Emily Clarke wrote:
>>
>>| Also, you can't use the Elk for full duplex since it doesn't have a
>>| duplexer.
>>
>>I'm a bit confused by this statement.
>>
>>The Elk Antenna is here --
>>
>>    http://www.elkantennas.com/2m4405element.htm
>>
>>in case somebody wants to see a picture of it.
>>
>>The main competitor seems to be this one
>>
>>    http://www.arrowantennas.com/146-437.html
>>
>>By default, the Elk antenna has one plug, and the Arrow II has two
>>(since it's two antennas at right angles to each other.)  If you
>>almost double the price, they'll throw in a nice little duplexer in
>>the handle and then you have one connector to worry about.
>>
>>I've got two radios sutiable for doing 2m/70cm satellite work -- a
>>FT-530 and a TM-D700A.  Both have a built in duplexer, both have only
>>one antenna connection, and both can transmit on 2m and receive on
>>70cm (and vice versa.)
>>
>>Are not these radios pretty `standard' for satellite work?
>>(i.e. 70cm/2m, one antenna connector, built in duplexer, can transmit
>>on one band while receiving on another.)  If this isn't standard, than
>>what is?  Two different radios, one for transmitting and one for
>>receiving?  Or radios with two antenna connectors?
>>
>>Why wouldn't I be able to do full duplex with one of these radios
>>using the Elk antenna and no extra duplexer?  Certainly, I can do it
>>with the little 1/4 wave whip I use with it.
>>
>>Forgive me if this is silly question ... I'm pretty new to this :)
>>
>>--
>>Doug McLaren, dougmc@frenzy.com, AD5RH
>>And in other news ... the pot called the kettle black again.
>
>
>
> ---------------------------------
> W0EEC - CM87tm
> AMSAT Area Coordinator - San Francisco Bay Area
> http://www.projectoscar.net    http://www.PlanetEmily.com 
> http://www.emilyshouse.com/experthams/ao7/
>
> Help Pay For 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 
----
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