Scott
Welcome back! Agree with previous comments on checking the power supply
first. What frequency range is affected?
Is the isolation transformer an ac mains isolation transformer or an rf
isolation transformer? Even if you're using an ac mains isolation
transformer an rf isolation transformer on the lead will probably be
required. For this transformer I've found that a conventional wound ferrite
transformer with the primary and secondary separated on the core work best.
Bifilar wound transformers are not the way to go here. If you have a
computer connected to your receiver a 600 - 600 ohm isolation transformer in
that connection can also improve noise pickup.
Any hope of transmitting again?
Jay W1VD WD2XNS WE2XGR
----- Original Message -----
From: "Scott Tilley" <sthed475@telus.net>
To: <rsgb_lf_group@blacksheep.org>
Sent: Thursday, September 11, 2008 12:10 AM
Subject: LF: AC Noise on RX...
Hi All
Been awhile since I've posted to the reflector. I'm pleased to announce I
have escaped the noisy clutches of the City and bought myself a nice piece
of land up the coast in a very quiet spot.
Presently I'm only using my passive RX loop which has a single turn
'sense' loop for coupling into the main multi turn loop... When the RX is
connected to an AC power power supply I get terrible AC growlers; however,
put the RX on a battery and bang not a peep of nasty AC noise.
I presume this is due to some coupling between the AC mains and the RX
system and my isolation transformer doesn't seem to help so I wonder if
someone could set me straight on what is going on here so I can solve the
problem.
Thanks for any support!
73 Scott
VE7TIL
| 