Hello Brett,
Sorry, this is a little off topic, but ...
Shunting loudspeaker terminals on an amplifier (or at the loudspeakers
themselves) may cause instabilities with some amplifiers due to phase
shift, causing them to break into oscillation well out of hearing range,
resulting in possible failure of the output transistors (at the very
least), and some embarrassment and expense to the applicator :-)
It's usually more effective (and will not cause any instabilities to the
amplifier) to place ferrite beads over the individual wires or over the
pair of wires (whichever works best) as near to the loudspeaker
terminals on the amplifier/receiver as possible.
Sometimes, due to the size of the connector terminals at the ends of the
wires, it is not possible or practical to fit a ferrite bead over the
wire. In those instances, you can obtain some split cores from Radio
Shack, Mouser, Digi-Key, etc. that will allow you to wrap several turns
of wire around half of the ferrite core that is temporarily opened,
after which you can close it again. Keep adding more of these devices
until you no longer have a problem.
73, Dale
WA8SRA
Brett gazdzinski wrote:
.... Some caps across the speaker outputs cured it
totally!
Brett
N2DTS
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