Hi,

(1987 - Plexi copy) - I carefully wired up 2 new jacks as depicted in the wiring schematic for the Interupt fx-loop. I tried it out without any fx units in the new loop and to my dissapointment the amp made some additional squeeling noises which I could regulate with the treble knob. Something was clearly wrong and I was as nervous as hell so I quickly switched it back off again. Yet I checked out the schematic again and it was fine.

To be honest I do not understand how it can work with the jack sockets I have. My logic tells me that the normal signal from the treble pot needs to flow across from one jack to the other and then return to the phase inverter stage until an fx-unit is inserted. The sudden arrival of a jack socket to and from an fx-unit would bypass the 'across' mode - right? But I think it is the opposite...

Someone here said I need 'switching jacks'. So I ordered 2 x Cliff 6,3 mm Mono jack sockets which are supossedly "switched'.  Yet the 2 pins on the left run across the center of the jack socket yet they do NOT bridge all the way to the pins on the right - indicating that the right-hand pins are standing free. This means to me that the signal cannot flow across from one jack to the other when no fx unit is present (or something is going on inside which I cannot see...).

Either they should not be switched OR they have sent me the wrong ones.

BIG Q's :-  Does the schematic apply to non-switching jacks? Do I need switched ones at all and how can I see if they are switched?

Cheers Brett