[Elecraft] KPA500 - linear power supply

[Johnny Siu]

I notice KPA500 is using a linear power supply.  The technology of switching power supply is now very mature.  Is there any reason why linear PSU is used instead of switching PSU in KPA500?  I just think a switching PSU will make KPA500 more lighter and the linearity of the amplifier will not be affected by fluctuation in supply voltages.
 
A lighter KPA500 will make it more portable for Dxpedition.  My questions may be discussed somewhere in the past.
 
Any advice?

TNX & 73,


Johnny VR2XMC

從︰ F5vjc <foxfive.vjc at gmail.com>
收件人︰ Henk Remijn PA5KT <pa5kt at remijn.net>
副本(CC)︰ elecraft at mailman.qth.net
傳送日期︰ 2011年05月11日 (週三) 9:26 PM
主題︰ Re: [Elecraft] KPA500 - stacking possibilites

As the KPA 500 uses a linear PSU there obviously is a mains
transformer within the cabinet.
I know this is a toroidal type transformer, which is good, but can we
assume that placement of the Amp with respect to the K3 is non
critical, for magnetic hum coupling.

How immune is the K3 to this effect? Has placement of the KPA 500
w.r.t. the K3 been tested  for any ill effects?

73, Deni
F5VJC