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kicad/README.md

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+(THE PCB)[!../doc/audioMux-brd.svg]
+
+There are a total of six solderjumpers on the board:
+
+# switching to the barrel jack as voltage supply
+
+*JP3* and *JP4* set the source for the supply voltage. 
+*JP4* connects the voltage input to the barrel jack, *JP4* connects it to the USB +5V rail.
+
+Per Default JP4 is closed and JP3 is open, making the default way of supplying voltage the USB jack. 
+
+If the Barrel Jack should be used, then **JP4 has to be opened first** by cutting the trace which shorts it by default, otherwise **the USB voltage will be shorted with the barrel jack, causing potential damage to the USB port**.
+Afterwards, *JP3* can be closed with a small blob of solder. 
+
+# activating the equalizer on
+
+*JP1* and *JP2* connect the output of the Audio switching part of the Rohm chip. 
+When left in the default setting, they will connect them to the output jack directly, bypassing the Equalisation part of the chip completely.
+
+By selecting the other possible path, the equalisation circuit becomes usable. For this to work, 
+*JP7* and *JP8* have to be closed with small solder blobs as well, since those connect the equalizers 
+output to the output audio jack.
+
+# Assembling the rest 
+
+For assembly of the board, check the (documentation folder)[../doc]. It contains the (interactive bill of materials)[../doc/interactive_placement.html],
+which indicates what components go where.
+
+Also take a look at the (BOM)[../doc/BOM.xlsx] for what components can be sourced where.