Input Jack Wiring

[ajeffcote]

On the Fender DRRI that I am refurbishing,or converting,the input jacks both have a 1 meg resistor between the output connection and ground.Why?What purpose does it serve?Why not a 500k or a 2meg or some other value?
Also,I am installing a Hoffman AB763 board,which uses a ground buss on the back of the pots.The input jacks are grounded to this buss.Should I use insulators between the jacks and the chassis?

[Enzo]

I assume you mean from the tip connection to ground.

It provides a DC path to ground for the grid. Normally your pickup resistance does that and you can more or less ignore the 1 Meg in prallel with the much lower impedance of the pickup.

But what happens if there is an FX pedal between the guitar pickups and that grid? If that FX unit has a capacitor output, then there would be no DC path to ground for that grid. It could charge up or down to whatever it wanted. That resistor is insurance. COuld it be 470k or 2 meg? Why not? But 1 meg is a common standard value, and is right out of the book.

[ajeffcote]

That makes sense.I figured it was merely a precaution.
Thanks.