Aerial grounding and QRM pick-up: theory & practice
On Sat, 22 Sep 2007 16:05:39 +0100, Highland Ham
wrote:
Even better: If no AC is required but say 12 -14 V-DC , run the receiver
from a sealed lead-acid battery and only have a RF earth.
If charging from mains ,one could switch-off charging while receiving
and only put charger on battery or batteries while transmitting.
Hi Frank,
You are a proponent of one of my suggestions; yes, battery operation
(as I have as well) solves many issues.
My complete station runs on 12V batteries (charged by 2 solar panels and
a wind gen) ,resulting in NO mains born interference .
however when the batteries are on the charger all the time the batteries
will probably 'absorb' any mains noise ;
This is true only if the interfering voltage appears across the
battery - a rare occurrence unless you are mobile and speaking of
generator/alternator whine.
If batteries are float charged, then there is a path from the radio,
through the batteries, to the charger, to the mains and common mode
follows that path. Similar common mode paths of (in)convenience take
time to discover - like an external DSP powered by a wall-wart.
73's
Richard Clark, KB7QHC
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