GEO AB-Y - using DPDTs, 9V DC jack, 2 LEDs, and 9V Charge Pump

[mydementia]

Hi Guys.
I've been testing my first circuit (the GEO Transformer Isolated AB-Y splitter) and have a few questions.
Here's the layout I sortof followed: http://www.generalguitargadgets.com/diagrams/amp_ab_lo.gif <thanks GGG!>

1) In my initial testing, I followed the schematic for the A/B switch.  When I plugged my rig into the circuit (hadn't cut up the box yet) there was substantial buzz on both outputs.  Probably ground loop - but I'm not really sure where I'm going wrong.  I know I need to isolate all four 1/4" jacks and the DC jack...anything else?  Before anyone asks - I have checked voltages on the MAX1044 and everything looks right.  For my testing, I just laid the circuit on a piece of wood and made sure nothing was touching - maybe I need to put it in the enclosure to isolate it...

2) I want to use the two DPDT switches to control the outputs individually - so...when I step on switch A, it turns A 'on' and when I step on switch B, it turns B 'on'.  To select A and B just stomp on both - right?  It looks like I wired the switches wrong...based on the referenced layout - how SHOULD I have done it?

My end goal:
Isolated AB-Y switch using 2 LEDs, 2 DPDT switches a 9V DC jack feeding the 'single battery' 9V Charge Pump circuit.  All I'm trying to do is allow myself to stomp a switch to route my guitar input to my Peavey XXX input or to my Vox ToneLab (then into my Peavey Effect Return).  At the moment, I have to swap cables all the time (I should really adjust my set-list!).

I'm planning to make the BSIABII (also from GGG) next (since I ended up with an extra 1590BB enclosure) and want to be sure I understand how these things are supposed to work.

So...if any of you can help - I'd really appreciate it.

APPENDED: I just modified the layout (in Paint) to reflect the way I've wired my switches - hopefully, you'll see something screwy.  It might have something to do with the shared 'gray' line coming out of the 100uF/0.1uF caps.
http://www.geocities.com/mydementia2/MusicStuff/DIY_Stuff/ABY_Layout_MOD.JPG

Mike

[mydementia]

Hi guys.
I realize my last note was probably a bit vague...so let's try it this way.

I've got the GEO Isolated ABY switch wired per the original schematic now <here: http://www.generalguitargadgets.com/diagrams/amp_ab_lo.gif> (I abandoned the individual switch scheme for the sake of troubleshooting).  So...the following recording is what I get on all 3 outputs now:
http://www.geocities.com/mydementia2/MusicStuff/DIY_Stuff/ <select BadABY2.mp3>

Any thoughts on what I've got going on?  I'm thinking that the Max1044 isn't as whine free as advertised...unless it's bad (I haven't tried a new one...).

Thanks in advance.
Mike

[bryantabuteau]

I'm sure R.G. will chime in here, but I had issues with that layout when I tried to build it.  Theres another one on the site ( updated hum free splitter/A/B/Y ) www.geofex.com that worked for me with no hum/buzz problems whatsoever.

heres a little discussion i had a while back that might have something useful in it :
http://www.diystompboxes.com/smfforum/index.php?topic=27538.msg188114#msg188114

[mydementia]

Thanks for the heads-up.  It stinks that I chose an obsolete schematic for my first build!  Who maintains the GGG pages?  I thought I couldn't go wrong with a schematic with so much information!

So - it looks like I get to rebuild most of the circuit... not a bad thing, I've had this one together and apart about 5 times thus far.  Does anyone have a good point-to-point layout of the 'new and improved' humfree2 version? (ref: http://geofex.com/FX_images/humfree2.gif) 

What about ideas on using two DPDTs and 2 LEDs (stomp left - A Channel is on, stomp left again, A goes off - stomp right, B Channel is on - stomp both - Y).  My modified layout (http://www.geocities.com/mydementia2/MusicStuff/DIY_Stuff/ABY_Layout_MOD.JPG) made sense to me but didn't work. 

Any additional help you can provide will be greatly appreciated.  Since I'm taking the thing completely apart again, at least I'll get the chance to paint the box!
Mike

[bryantabuteau]

maybe i'm looking at it wrong, but according to your diagram, if say A is switched off, the way the switch is wired, it would be attaching the a signal to ground.  but even if the B switch is 'on' the B signal is always attached to the A signal and would be connected to ground as well?

to fix this, you would not tie the top poles together on the switches i think, but still, leaving the inputs (primary) of the transformers hanging and not grounded was causing the hum problems I had with the same design.

take everything i say with a huge grain of salt, i'm a real beginner.