Be extremely awsare of any "switching power supplies"
these are a nightmare, generally, in a radio environment.
Stay away from these supplies..confirm that it is not
a switching supply.
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Professional receivers like the ones from Watkins -Johnson have internal
(obviously high quality) SMPS

Also, the battery back up power supply has
the same problem in a radio environment...they
emit unbearable noise on most radios..particularly
on the 80/75 meter bands.
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I have an APC - Back-UPS PRO650 less than a metre away from my TenTec
transceiver and do NOT suffer from noise on any band ,because of this UPS
(which is always on -line).

Frank GM0CSZ / KN6WH