ok.  the major advantages of the switching supply are size, weight, and 
eficiency.  They are smaller, lighter, and more power efficient.  Also, 
usually sound quieter.

Disadvantage is that many if not most create rf noise.  The better ones are 
pretty darn quiet.
I have the alinco dm330v and it is pretty quiet in the ham bands.
However, it does make a good deal of noise on am broadcast.  This can be 
moved around so as not to interfere with the station to which you are 
listening via an adjustment on the supply.

This has been a very good supply for me.  32 amps surge, and smaller than a 
shoe box.  weighs maybe 5 pounds.

However, I also have an mfj 35 amp surge supply. This is a conventional 
supply, weighs about 20 pounds, and is roughly comparable to the astron of 
the same rating.  No rf noise, but is considerably louder.

There are other switchers, the  most highly rated I have heard of are the 
alinco, astron, and gamma research.
The gamma research is interesting because it is well regarded, and extremely 
small; more like a laptop charger in size.

Hope this helps.

----- Original Message ----- 
From: "Dave Basden" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, April 02, 2014 12:48 PM
Subject: Power Supplies (Switching or Not)


>I may be in the market for a new power supply for my Kenwood
> TS-590.  I hate to pay the price of a Kenwood PS-590, so am looking
> elsewhere.  It should probably be about 25 amps 13VDC.  Switching
> power supplies seem to be about half the price of the old
> standard.  They're also a lot lighter in weight.  There must be some
> advantage to the old standard supplies or they wouldn't still be
> available.  What is the difference and why should I consider the more
> expensive standard supply?
>
> 73,
>
> Dave, W7OQ