Fulltone A/B Box A/B/Y

[hendrix2489]

hey guys just wanted to spread this out there.  I have seen a couple requests for a/b boxes and here is the Fulltone A/B Box.  I had a spare very small enclosure i think its a 1290ns,  and a few jacks, so i built it in what felt like an hour. Extremely easy wiring with 2 status led indicators.  Here is the url        http://fulltone.com/qaframe.html

and here is an example,

i have not cleaned up the box or decal-ed it but it is just an example.  Hope this helps. 

[jzilla]

thanks for this.  could you tell me how to add a battery?  cheers!
-j

[z1]

i'm still looking for something like this that also does 'Y' not much luck yet..

[Barcode80]

you can easily mod this one to do Y. just need two switches. one controls a or b, one selects between the A/B section or Y.

[jzilla]

doh!  i got hi-jacked!   
what would the wiring be to hook up a battery snap?  i'm sure it's very simple...
thanks!
-j

[Barcode80]

use a stereo jack for input, solder black battery lead to the ring terminal. if you already have a dc jack in there, wire the positive of the battery to the secondary positive lead on the jack like in the diagram below. if not, just wire the positive of the battery snap directly to the positive ends (light purple in the pic below) of the LEDs.

[jzilla]

thanks!
-j

[Barcode80]

just an FYI to save you some hairpulling, the graphic mistakenly shows the short leads of the LEDs as positive, in reality you would want the leads on those LEDs reversed from the way i drew them. Sorry!

[jzilla]

cool.  thanks for the heads up...

[jzilla]

so i'm having a problem getting the led's to function properly with the battery.  the only way i get them to illuminate is to wire the negative battery lead to the negative lead on the dc jack.  if i wire the neg battery lead to the ring i get nothing (i do have a cable plugged in to the input).

just to recap i followed the above instructions from fulltone (http://fulltone.com/PDfFiles/AB_switcher.pdf) and am trying to add a battery.

any ideas?

thanks,
j

[Barcode80]

are you positive it's the ring you wired to? (sorry, i have to ask)

take out your dmm and check for continuity with a cable plugged in between the ring and sleeve connection.

[jzilla]

no problem.  i'm pretty new at this and definitely have some gaps in my knowledge...

i got it to work by connecting a wire from the negative terminal on the dc jack to the ring and connecting the neg battery lead to the ring as well.  that seems to make sense to me.  before the dc jack wasn't wired to the input jack at all.  everything's working correctly so can i assume everything's cool?

thanks,
-j

[Barcode80]

it will work as you have it wired, but it will not turn off when you unplug the guitar cord. connect the wire from the dc jack ground to the sleeve of input, then wire the battery ground to the ring of the input. then the battery is only active when the cable is in.

[jzilla]

oops.  that is how i wired it - just described it wrong (which shows how much of a hacker i am...).
thanks!
-j

[hendrix2489]

Here is the finished project.  No noise no popping , it is a great build.  ed and green led for status indication