[Milkymist-devel] J3 redesign for rc4

[Joerg Reisenweber]

Hi Adam,

Yes, this looks pretty decent, the schematics (p.1) as well as the selected 
varistor which is a nice component and perfectly suited to replace the 47pF. 
:-)

As there's always sth to improve :-) I suggest:
cut J1:3<->2, connect J1:3<->1
cut J1:5<->4, connect J1:5<->1
rationale: connect unused input to GND -> less noise

cut connection and insert a 100R, from joint C19*R17 <-100R-> J2:2,3 
cut connection and insert a 100R, from joint C21*R18 <-100R-> J2:4,5
Rationale: some protection for LineOut amp / internal clamp diodes there 


consider 2pin with jumper to GND for TP50
rationale: again noise of unused input

consider make J23 a 4 pin: 1:AUDIO_AGND 2:CD_L 3:CD_R 4:CD_GND
Rationale: convenient variety of input configs, at least possibility to short 
CD_GND to AUDIO_AGND for common-GND design setup

Good job, kudos
/jOERG