Greyhill switch and Nobel pot problemH

[porfi4ever]

Hi everyone, I'm finishing my gainclone kit( Peter's kit) but having problem with the greyhill switch and nobel pot, being a newbie I have no idea how to wire those thing specially the greyhill switch!. I did a search but to be honest, didn't get it and I was trying to set the 4 position for the switch but mess it all, now don't know if the greyhill switch is ok. About Nobel pot , Do I have to cut pin 1 and 6? pin 2 and 6 to input, but where? to channel boards? pin 4 and 8 to ground, should be signal ground on channel boards? please, if can give me some advise with diagrams it's poing to be better for me. Sorry just a newbie.

[Peter Daniel]

On the Nobel pot, you don't use the pins which are on far right (shaft facing to you, pins oriented downwards). Each deck is used as separate channel. Left pin is ground, center pin is output, right pin is input.

If nobody posts info on Grayhill, I'll do it later today.

[porfi4ever]

Thanks Peter, by the way the chassis looks superb! Everything fits properly. Sorry Peter but still confuse, when you say ground, is signal ground? same for input, it's going to be IN on board? and what about output. Again sorry for my dumb questions.

[Peter Daniel]

When I say ground, I mean signal ground. The signal (and grounds) go throught the Greyhill switch first and then to the pot. Ground from the switch (or for that matter from RCA input ground) goes to ground pin on the pot and from here to the SG pad on a PCB. The signal from he switch (or RCA input for that matter) enters the pot through the right pin (as above) and goes out from a center pin and then connects to IN on the PCB.

[porfi4ever]

Thanks Peter, I got it. When you can please tell me about the greyhill switch and how to connect the RCA inputs and ground to it. Again thanks in advance.

[Peter Daniel]

Here's the drawing of Greyhill switch. To set it for 4 positions, you put the pins as marked: first one goes right above the groove (cut out) in a threaded bushing, the second one defines number of positions and should be inserted after 4 spaces counting from first pin. For 3 positions you place it one hole closer. Put tape over the holes, so pins won't fall out.

The tabs should be connected as marked, the separate ones are outputs, the ones in a row counted clockwise from output pins, are inputs. You can choose to switch both signal and ground for both channels independently and than you use both decks and all 4 output pins. An elegant way to do it, is use one deck per channel and upper pins for signal and lower for ground (switching). Use second deck for another channel, but this time use upper pins for ground and lower for signal (switching). This provides some extra isolation between both channels.

Best way is to use ohm meter to check connections on a switch.

In 4th position (if going by front panel markings) you should be getting Mute, which means input connection on those tabs (on a switch) should be grounded. That effectively grounds the amp's input and provides no signal.