Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old August 26th 07, 11:03 PM posted to rec.radio.amateur.antenna
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 234
Default Sun noise

"Jeff" wrote in
. com:

I would like to see what mods are made to the 221 to do that and also
what kind of antenna system. I have a 221 I am using with a gasfet
preamp in the shack that should be less than 1 db of noise fugure
and about 20 db of gain. The antenna is a klm 22c and 75 feet of
9913 type of coax. I can just see some sun noise with the antenna
aimed at the sun. It sure does not deflect the smeter several
sunits. The antenna is on an azel mount. I am sure the system is
working as I compaired it to an Icom 706 and another antenna that is
mounted on a tower and I am getting about the differance in signal
levels I would expect at the horizon.


The 75 feet of coax is your problem!!! What is the point of a 1dB NF
preamp with all that loss ahead of it? To see the benefit of the low
noise figure the amp must be before all that cable loss!!


Yep...when I moved, I put in hardline and lowered the antenna a bunch.

That's when I started to hear other things besides the sun. And I could
plot it. When the galactic plane was in front of the antenna, the noise
floor would be up an S-unit from base.


--
Dave Oldridge+
ICQ 1800667
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
"Noise" antenna for MFJ-1026 "Noise Canceling Signal Enhancer" Eric Antenna 1 February 24th 07 06:01 PM
Shortwave Listening (SWL) Noise in Urban {Downtown) Location - Anti-Jammimg {Anti-Man-Made-Noise} Shortwave Antenna System RHF Shortwave 0 March 29th 06 05:25 AM
WTB: HP/Agilent 346A (or B) Noise Source for HP 8970A Noise Figure Meter Carl R. Stevenson Homebrew 0 January 21st 04 04:20 AM
Automatic RF noise cancellation and audio noise measurement JGBOYLES Antenna 25 August 11th 03 01:07 AM
Automatic RF noise cancellation and audio noise measurement Dave Shrader Homebrew 35 August 11th 03 01:07 AM


All times are GMT +1. The time now is 06:05 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017