Even more mb6582 questions

[Davo]

1.  Your instructions state that R6 for cores 2, 3, and 4 are not needed.  What does R6 on core 1 do?  Am I hurting anything by soldering in those resistors anyway?

2.  What part number do you recommend for the trimpots?

[Wilba]

R6 is a pull-up resistor to keep the PIC's Rx pin (serial input) high when there's no signal coming from MIDI In, or the optocoupler (6N138) isn't connected. Since this board always connects the Rx pins of all the PICs, R6 on the slave PICs are redundant. It does not hurt to solder in those resistors - this is how people have connected multiple Cores together for years.

SmashTV can help you with a Mouser part number perhaps... I got mine from a local electronics shop the first time, and the second time from SmashTV (as a base parts kit).

[Davo]

Okay, I'm now soldering R70 through R77.  You said previously that these are part of a passive mixer.  R70 and R71 do indeed connect to J70.  But I can't seem to figure out where R72 through R77 connect to besides the SID outputs.