Paul,
The main advantage of a preamp is increasing your sensitivity by
lowering the noise figure of your receiving system. You lose some of
that by locating the preamp in the shack. Any coax loss between the
preamp and antenna adds directly to the overall NF: 80-foot of
LMR-400 is 1.2 dB
- Original Message -
From: Edward R. Cole kl...@acsalaska.net
To: Paul Delaney - K6HR paul.hamra...@verizon.net; amsat-bb@amsat.org
Sent: Monday, March 14, 2011 7:54 AM
Subject: [amsat-bb] Re: Using Preamps In Shack
Recently I lost one of my eme preamps on my tower and used a preamp
Paul;
Check the electrical departments at Home Depot and Lowes for inexpensive
plastic boxes made by Carlton. These are fully weatherproof boxes
without any knockouts that are excellent for weatherproofing
preamplifiers. You will probably need some type N bulkheads that have a
long neck so
Joe speaks wisdom when he says get a bigger one that you think you need.
I have a whole pile of those boxes in the garage because I thought they
were big enough for the project I had intended to build in them.
73, Jim
On 03/14/2011 08:13 PM, Joe Leikhim wrote:
Paul;
Check the electrical
Bring the parts, cables plus connectors to the store when shopping. The
biggest problem is cable bend radius.
On 3/14/2011 4:39 PM, Jim Jerzycke wrote:
Joe speaks wisdom when he says get a bigger one that you think you need.
I have a whole pile of those boxes in the garage because I thought
Yes I have done this. The feed line loss will essentially add to the noise
figure of the pre amp, which is not desirable, but in my case with a 70 foot
run of 9913F7 the arr gasfet preamplifier was still worth using on 70 cm.
Sent from my iPad
On 2011-03-13, at 9:36 PM, Paul Delaney - K6HR
