Mike,
Pre-amps are fine if you need to reduce feedline and connector loss, for those
lucky few that have antennas way up on commercial towers and have significant
loss. Otherwise, nada. Signal to noise is not improved and can be effected
negatively. Pre-amps can also be easily overloaded by pager and other nearby
signals. Lastly, the pre-amps are physically sensitive devices when it comes to
EMP...IMHO. If you want to improved receive capture area or coverage think
satellite receivers.
73,
dave
wa3gin
----- Original Message -----
From: Mike Morris WA6ILQ
To: Repeater-Builder@yahoogroups.com
Sent: Wednesday, August 19, 2009 4:43 AM
Subject: Re: [Repeater-Builder] ENHANCED RECEIVE
At 07:47 PM 08/18/09, you wrote:
>I have heard of repeater owners using pre-amps on the receive side
>of the duplexer and adding 1 pass-reject cavity after the preamp and
>placing a pre-amp on the pass reject cavity to enhance more receive.
>
>Does this work or is it a myth?
>
>Artie
>k2aau
Depends on if you have enough headroom in the duplexer and enough
system isolation.
<http://www.repeater-builder.com/rbtip/preamps.html>
While this is on 900MHz the theory and comments are just as applicable
on 2m, 220 and 440.
<http://www.repeater-builder.com/tech-info/speaking-of-preamps.html>
