On Feb 21, 4:58 am, "Joel Koltner"
wrote:
How come we have all been conned into these switchmode things? - by
their very nature, without a lot of effort, they are noise generators.
Their cheap to make, thats their only advantage - everything else is
part of the spin cycle.

Other advantages include much better power efficiency and much lower weight.

It's not particularly difficult to make a switcher with very good (meaning
very little) noise output, but relatively few applications call for it, and
given how incredibly competitive the power supply arena is, it's not
surprising that a lot of companies drop a few components to reduce their costs
at the expense of noise.

re power and weight - I was having a rant, so deliberately left out
the inconvenient facts.....(Yes, I thats unusual, isnt it - I must
reprimand myself)

And yes, will readily concede the " they can be well designed bit"...

But they are not. The percentage? - dont know. All I can do is hear
them, on air. Went away at Xmas, remote caravan park, MILES away,
looking forward to HF radio . Nope, surrounded by modern caravans with
12v systems, run from noisy SMPS power supplies/battery chargers....it
was better, 80m QRM was S3 instead of S9+

Gosh, modern electronics IS wonderful, isnt it....

My point stands.

Andrew VK3BFA.