programmable 10 WAY FX Switcher

[gecko_blaster]

Hey Guys,

Right after 6 months of research, drawing out schematics and annoying the hell out of all the electronics engineers at work I've now finished the schematic for my FX Switcher. I've based the ideas on those of the Carl Martin Octaswitch but with a few differences. I took out the Buffer option as anyone competent enough to build this beast is going to know how to build a buffer pedal. I added an extra 2 FX banks as well as 10 way Dip swtiches are about the same money as 8 wayso it seemed silly not to.

The amp channel selection is based on my Marshall DSL 50 which has the foot switch mod done. I never use B on Channel 2 so it's geared towards switching a/b on channel 1 and channel 2. These can be selected via dip switches for when the banks are selected or by latching switches when all the banks are by passed.

Anyway I'm hoping somebody else takes a keen interest in this as I've drawn it  in Autocad and need it moving to something like ALTIUM or as I've started with KICAD, ready to create a PCB layout.

Anyway if anybody's interested the schematic can be seen here:
http://freepdfhosting.com/dbf2fb60f0.pdf

It's not that clear to see all the chip names etc. but if you are interested further let me know and I'll email you the DWG.

Anyway interested to hear all your feedback on this.

[pinkjimiphoton]

wow looks cool, but definitely hard to read... just glanced at it, will check it out when i get a chance, thanks!!!

[KMG]

My point of view on FX Switcher.

Control board.
http://milas.spb.ru/~kmg/files/projects/looper/Looper.pdf
One loop module, one of R6..R17 (only one installed) defines number of loop assigned to module.
http://milas.spb.ru/~kmg/files/projects/looper/OneLoop.pdf
DIP switch module, one of R2..R9 (only one installed) defines number of preset assigned to module.
http://milas.spb.ru/~kmg/files/projects/looper/PB.pdf
All boards connected together via 24 way flat cable (except signal wires).

[gecko_blaster]

KMG That looks like a complex beast, have you actually built it? Looks like it maybe quite costly with several PCBs

Thought I might try to explain my schematic a bit futrther.

I've designed mine to go on 1 PCB and use a 16 bit latch chip and DPST relays, if FX loops 8 - 10 are selected the the dry signal either goes to FX jack out or to the next relay etc. etc. in Series to the final output jack. My wah is already true bypass and I'm hapy enough to click that on and off whilst I'm using it so thought that 3 before amp fx loops was enough.

The Fx loops 1 - 7 are designed to take the wet signal or fx send signal or post pre-amp signal (whatever you want to call it). Again the Relays connect in series. using DPST means if the Effect is not selected then the signal goes into true bypass (nice).

so basicly you select a momentary switch from banks 1 -  10 it latches the chip to the dip switch associated with that bank.

i.e. you select bank 2, DIP switch 2 now has a 1 logic going to every position on the dip switch switch, so just the set the dip positions to turn the fx loops you want on or off on that switch. It either turns the relay on or off.

(the signal isn't connected straight to the relay, a ULN2803 chip is in place, a clever little chip which just switches the selection down to ground... Genius)

The same latched signal is used to select the amp channel as well.

I've placed LEDs across the coil on the relays so this should indicate when an FX loop is selected and which channel is selected. There is also some LEDs coming off the latched signal so you can tell which bank you have selected.

I've tallied the components up to about £70 so hoping to make my own PCB using the press n peel technique to keep it around £100 (I've managed to get this down a lot further by getting samples sent to my work but if you don't have this option that's the cost your looking at.)

I've also kept the whole circuit to 5V using a 9V regulator, that way you can just plug it onto your daisy chain.

[KMG]

My main idea was to create a modular system, so I can vary the number of loops by simply adding / removing modules.
Also usually cheaper to order many of the identical small PCB's, than to order one large PCB.

[Hatredman]

Gecko, your PDF is not online anymore.

[armdnrdy]

Gecko, your PDF is not online anymore.

And he hasn't visited this site in about a year!

Punch on his name...message him or....there is an email address  that might still be good.