jhm731;213879 Wrote: > Sean- > > If you were concerned with EMI/RF energy during the design of the > Transporter, why do you still have an smps with no shielding inside the > unit? > > Why not a linear PSU for all voltage rails?
I did in fact test both of those ideas and there was no significant difference in EMI or any other kind of noise. That SMPS is simply not a source of noise to be concerned with, which is exactly why I chose it. The only difference you'd get by putting a linear supply in it's place would be that the system would weigh a couple more pounds and run a hell of a lot hotter. Probably hot enough to need a fan or some beefy fins on the side. The circuits which it powers are high-current things which are not sensitive to ripple, such as the display filaments, the magnetic braking mechanism in the knob, and the 1.2V supply for the CPU core. It also powers the auto-ranging circuitry which measures the incoming line voltage and configures the transformers properly for the linear supplies. For that purpose it's nice to have a PS which can comfortably handle a very wide range of input voltages. There are a lot of audio companies who do things "just because", but that is not the way I engineer our products. -- seanadams ------------------------------------------------------------------------ seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=36626 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
