Hi John,
Yes, the brushes are very noisy if you do not bypass them with capacitors!
The value is non-critical, but certainly much less than 0.5 uF! I use any
convenient value between .001 and .01 uF at 1 kV and they completely
suppress all RFI. Use one capacitor per brush, connected directly between
the brush-holder and the case of the motor (I use solder lugs under the
nuts adjacent to the brush-holders).
73
Frank
W3LPL
donovanf@sgate.com
On Wed, 15 Jan 1997, John Swiniarski wrote:
> What tricks are in use to eliminate the noise caused by arcing
> prop pitch brushes? I been told using .5 mF coaxial capacitors at
> the motor will help but can't seem to find any. Any suggestions?
> John K1OR
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