I respectfully disagree with the general assessment regarding switching
power supplies.
I personally own and use 3 switching supplies available from a
respectable US company and these are types used by many hams. Having
measured mine with my HP Spectrum Analyzer, I find the radiated noise
from these supplies is typically 20 db to 30 dB below the noise floor
found on HF bands. I don't see that this noise would contribute to
missing any weak DX signal. These supplies do have a CORCOM filter on
the input and chokes on the output and are contained in a metal case
which is connected to 3rd pin ground.
I also find that many if not most commercial communications system now
use and incorporate switching supplies in their products.
The earlier computer charger/supply is in a plastic box and has none of
the obvious filtering. It is also made offshore.
73
Bob, K4TAX
>
>
> I can assure you that a switching power supply made in
> the manner of modern consumer products will either cause,
> noise in HF radio equipment when new or at a later time.
> Avoid switching supplies at all costs, or be prepared to
> toss them, filter them, or live with the noise.
>
> Since they are everywhere running everything from your
> laptop to your commode, it will be a long war.
>
> I have had some success with the following setup. I have
> a cast box with a filtered AC jack on one end and a set
> of feedthru terminals on the the other. I put my laptop
> supply inside the box, connect the AC and output leads,
> and then screw down the lid. It it might be possible to
> build a larger case setup to hold the assortment of wall
> warts, power supplies, etc. which are involved in the typical
> ham station.
>
> The light bulbs will be a bit more difficult.
>
> de K8RYU
>
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--
Disclosure:
I am a Tentec Ambassador and compensated according to the Tentec
Ambassador plan. I serve as a volunteer beta test person for the Omni
VII, Eagle and Argonaut VI products. Otherwise, I hold no business or
employment interest with Tentec.
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