[ARC5] Adventures in Battery Ops

[Leslie Smith]

  Hello Bill,
  I'm interested in the symptoms of mains-borne noise in your set and
  reduction in noise when operating from batteries.

  I'm considering the problem of noise here too.  I have some
  interesting stuff "going on" here.
  One particular switch mode supply (for an MP3 player) thinks it's role
  in life is perimeter duty.
  The switching noise rampages up and down the band, incrementing the
  frequency in steps as it marches over everything. 

  Do you know (in your set-up) how the noise gets from the mains into
  your receiver?
  You seem to be saying that you can't connect a
  transformer/rectifier/regulator to a battery + receiver without
  increasing mains-borne noise.
  In other words the mains-noise isn't 'filtered' by the battery.

  In the notional system I WAS considering (until I read your posting) I
  had a power supply trickle-feeding a 12V battery.
  The battery would feed the filaments AND an inverter.  The inverter
  can produce any B+ from 45 to 180 volts.
  I have the inverter - but haven't listened to see how noisy it is in a
  well shielded box.
  
  It seems (from your description) I can't run the power supply AND
  receiver at the same time without the penalty of noise.
  At the same time it seems remarkable that there isn't some filter that
  can remove mains-bourne noise.

  Comments?

  73 de Les Smith
  vk2bcu at operamail.com

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