Urgent Help Needed! ABC Pedal

[Jaicen_solo]

Ok guys, I ditched the Eagle layout software. Couldn't get my head round it, so I've worked up a preliminary layout by hand.
It's 3:53am here, so it's not complete, but my insomnia will only stretch so far
Can you guys take a quick look at my work so far and tell me if i'm on the right track? That 74C373 is causing me some serious headaches. I guess it's intended to be used on multilayer boards, but i'm having to rout the relay signal between the ic pins. Not thrilled about that, but I can's see any other way to do it. Quite pleased with the tidy 40106 section though.
Goodnight everyone!

Schem can be found here: http://storage.msn.com/x1p3q6ujd6xcOpOfW-G0f53Of6axOUXKnK79AStM-yR3ZVbUZZYUAvj5Q0sA86kzzgpPV6bdQIGJHS6XOj6sxevwLwQtntCL6DPSkZne0WZgvbKe6117W-P2-QdJJjx4lGyDxXEhcFYrpSQcQRdN7crrQ

[niftydog]

Not thrilled about that, but I can's see any other way to do it.

Can't you just run them out towards the top of the page, kind out the end of the chip?

Otherwise, keep in mind that jumpers can be used to effectively place "tracks" on the upper side of the board akin to double sided boards.

[Jaicen_solo]

I guess I was a bit tired last night and not operating at 100% (more like 10!) .
Anyway, i've redone some of the layout. In the end I had to use two jumpers for the power connections, but otherwise I think it's quite a tidy layout. Pretty pleased with it.
Just got to do the relay layout now and it's ready for prototyping! Can somebody check through and make sure i've not made any stupid mistakes.
Thanks.

An updated Schem can be found here: http://storage.msn.com/x1p3q6ujd6xcOpOfW-G0f53Of6axOUXKnK79AStM-yR3ZW6XVeHASoTm8JHBqws2tdjjTBz74Aiv8g1Rz7DqC_jMZfAxrgTpxJAh-BRh38SfbYsXPeCtF99WYHai69ndKMs-UJ748KW3yr_cKDza-rKiA

[boogietube]

Here's what I built. Check it out.
http://www.morleypedals.com/downloads.html
Look for the DISCONTINUED ABC Box and download the schematic.
It works great!!
Sean

[Jaicen_solo]

Yeah, that looks super simple to build, but unfortunately its not really what i'm looking for. I need to switch the three inputs to one output, and I need only one on at a time. That last part was the hardest bit, which is why i'm using R.G's CMOS switching. I think it's quite an elegant solution and fairly low cost, if only the heavy duty momentary switches didn't cost as much as a DPDT!

[boogietube]

It DOES switch 3 inputs to one output and only one at a time. I have three guitars plugged into it and I switch between them using the switches. It's A or B/C  for the first switch and B or C for the second switch. Three led indicators. A lot less complicated.
Sean

[Jaicen_solo]

Yeah, I see how it works now. I guess it could be a much simpler solution, though it doesn't do exactly the same thing. If it was me, i'd want to have only one switch press, but this might be adequate. I'll speak to the guy tomorrow and see what he says.
Think i'll still develop the CMOS switcher either way, as it makes a nice remote FX loop switch which might be useful to me.

[Jaicen_solo]

Ok guys, I've found the time today to draw up a layout for the second half of my ABC switch. Everything is running off 12v now.
The relay driver now uses a UL2801A darlington array to drive the relays. Primarily for simplicity, since it's a single DIP package, as well as featuring internal inductive load protection. Led's can also be driven in parallel with the relays for ease of layout.
I've gone for SPDT relays, just because the DPDT layout was giving me headaches. Relays will be ultra-miniature 12v's that fit into 16-pin DIP sockets for easy assembly, maintenance. Can be found here: http://www.maplin.co.uk/Media/product_pdfs/yx94.pdf
All the relay inputs are sent to ground unless a control signal is applied to the driver circuit.

I'd really appreciate it if someone could give my layouts the once over, in case there's something i'm missing. I have a feeling that pin 10 of the octal array needs to be connected to +12v. Can't see anywhere else to apply power! (I don't quite understand that chip yet).