Jasen Betts wrote in a message to All:

 JB> Hi All.

 JB> I was tring to build a prototype that involved 1M resitors
 JB> but I couldn;'t get it to behave sensibly

 JB> I measured 400K between the tracks on the stripboard.
 JB> dunno if the 30C heat and 100% humidity had anything to do with
 JB> that.

Probably.  You also don't mention if it's phenolic or epoxy-glass,  which
seem to act somewhat differently in this respect.

 JB> so I stripped the components off the board and built the whole
 JB> thing free-standing between two wires...  seems to work now.

How high a circuit impedance are you trying to deal with?

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