[AMRadio] Receive Preamp question

[Jim Candela]

----- Original Message ----
From: John <razorback_fan1999 at yahoo.com>


Does anyone have a good recommendation for a preamp to
help my radio receive better. Thanks for any
suggestions. 

John W5HG



John,

   This is a very broad topic. In general you need enough gain to bring the ambient band noise (not man made noise) above the receiver noise floor. With more gain than that you will likely suffer a reduction in dynamic range and therefore be prone to overload. On VHF / UHF we sometimes need to add a low noise receive preamp at the antenna to boost the signal before it goes into a long and lossy feedline. On HF with Boatanchor receivers of low to modest design poor sensitivity becomes more of a problem on 20-15-10 meters and is seldom a problem on 160-80-40 meters.

  The following link covers this subject pretty well:

http://www.arraysolutions.com/Products/appnote_preamps.htm

  We have not yet discussed receiver bandwidth, mode, and noise reduction methods.

Regards,
Jim
JKO