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Russellc
02-04-2008, 01:43 PM
Thanks to SUBWOOF, (boy does he ever know these amps!)
My JBL/ Urei 6230 is working fine, with only one remaining problem. When the Amp is switched off, there is an annoying snap. My schematic does not show any cap going across the on/off switch, and the relay seems to be working fine. Any ideas on how to quiet this snap?

Thanks,
Russellc

subwoof
02-04-2008, 02:37 PM
A standard "snubbing" circuit across a power switch should have both a cap and some low resistance.

For club install lighting shows we would use a 10 ohm, 1 watt and .1uf 1000V ceramic disc cap wired in series across the switch ( or relay contacts if switching line voltage ).

It's important to use a high voltage cap ( 400V or better ) and any resistor between 2 and 10 ohms is fine - the larger resistor size is handy for direct wiring onto outlets, etc.

HOWEVER some loads react differently so some experimentation might be needed. This will also greatly extend the life of the switch but it might also allow enough voltage to bleed thru and light the neon bulb if you use a cap that is too large.

sub

Russellc
02-04-2008, 02:51 PM
A standard "snubbing" circuit across a power switch should have both a cap and some low resistance.

For club install lighting shows we would use a 10 ohm, 1 watt and .1uf 1000V ceramic disc cap wired in series across the switch ( or relay contacts if switching line voltage ).

It's important to use a high voltage cap ( 400V or better ) and any resistor between 2 and 10 ohms is fine - the larger resistor size is handy for direct wiring onto outlets, etc.

HOWEVER some loads react differently so some experimentation might be needed. This will also greatly extend the life of the switch but it might also allow enough voltage to bleed thru and light the neon bulb if you use a cap that is too large.

sub
Wow! That was quick......ok, a 10 ohm 1 watt resistor and a .1 uf 1000 volt ceramic cap in series across the off on switch...will do.

Thanks again,
Russellc