I've read in the service manual that the output muting relay is controlled by the circuits of Q21 and Q22. But where is the output relay? I can't find it anywhere on the schematics, I can't find it on the component placement diagram either. I suppose it is directly after the 10uF caps, and simply shorts to ground so there are no turn on transients, am I right?
Thanks in advance
/Freddie
Thanks in advance
/Freddie
The mute relay runs off of the Mute + and Mute - coming from Q21 & Q22. Q21 switches on and off more or less instantly once the rail comes up or drops. Q22 provides the delay on turn-on via the cap at the gate. The relay itself is not shown (at least not on the power supply schematic with the rest of the circuit--I didn't bother looking for it elsewhere), but it's not too hard to hook up a relay to Q21 & 22, then apply ground to the outputs. The IRF610 and IRF9610 have sufficient current capability to drive any reasonable relay coil for this application.
The circuit tickles me, because it's such an elegant way to use up out-of-spec parts from the gain stages.
Grey
The circuit tickles me, because it's such an elegant way to use up out-of-spec parts from the gain stages.
Grey
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