YUSSSSSSS! Vox V846 wah - first "build-from-scratch" success!

[philbinator1]

Finally!  man i'm pretty please about it, after so many failures.    i used Ulysses' vero V846 and put the circuit together (using 2x 2N3904 trannies instead of the MPSA18's) and then stuck it on the bread board with some jacks and a wah pot.  

http://www.aronnelson.com/gallery/main.php?g2_view=keyalbum.KeywordAlbum&g2_keyword=Vox+V846+Wah+1590B+Vero+Layout+Ulysses&g2_itemId=6509&g2_imageViewsIndex=1

the only thing is, i'm getting very clear radio stations through it...while being kinda funny, my mates' mate won't find it too pleasing.  is this happening because it doesn't have an enclosure yet?  or will i have to make a mod. to it?  cheers guys!

[EDIT]  oh and another thing, it says so put a 100K resistor on the pot but i didn't, not knowing where to put it...anyone know anything about that?

[deadastronaut]

just a thought..have you used a shielded input cable to the board?

this may be why you get radio!....

as for the 100k resistor i think it would be connected to pin 1 and 3...to change value of pot...

not totally sure about that tho...

dont know why you would have to!....hope this helps...rob.

[Brymus]

Congrats Phil,way to stick with it.
I think but I am not sure that a 10k-68k on the input(in series) will stop the radio intereference if that doesnt work try adding a small value cap shunted to ground (1n-10n),Or try doing a search here using the search function.
Wah's are pretty hard DIY projects ,So kudos for making a working unit.
Bryan

[oldrocker]

Congtrats.  I was curious.  Which inductor did u end up using?

[Paul Marossy]

Cool, feels good doesn't it? 

You know, a wah circuit isn't anything magical, it's like any other typical circuit around here. The only difference is that is uses an inductor. It's really a very simple circuit component wise. 

[oldrocker]

I've built one once and used half of a RadioShack audio transformer as the inductor.  It worked great although I never got the right pot or treadle enclosure for it.  I ended up using it in my Hystoresis as a filter to tweak out the clicking.  I'm sure the correct inductor would've sounded better.  I actually liked it as is though.  I still go in to pawn shops and thrift stores looking for a non-working wah enclosure.  Which leads me to my next question.  What treadle enclosure are you putting your circuit in?

[philbinator1]

just a thought..have you used a shielded input cable to the board?

this may be why you get radio!....

as for the 100k resistor i think it would be connected to pin 1 and 3...to change value of pot...

not totally sure about that tho...

dont know why you would have to!....hope this helps...rob.

what do you mean by sheilded cable; the input from the pcb or my guitar lead...?
i tried a 100k on the breadboard across pins 1 and 3 of the pot, and on pins 1,2,3 by itself..didn't seem to make a huge diff to me.

[philbinator1]

Congrats Phil,way to stick with it.
I think but I am not sure that a 10k-68k on the input(in series) will stop the radio intereference if that doesnt work try adding a small value cap shunted to ground (1n-10n),Or try doing a search here using the search function.
Wah's are pretty hard DIY projects ,So kudos for making a working unit.
Bryan

Cheers man!  the first one didn't work (was perfboard...f'ing nightmare for me) so i'm glad this one did.  once i get it running in the enclosure i'll try the cap, if i'm still getting the interference.

[philbinator1]

Congtrats.  I was curious.  Which inductor did u end up using?

Hmm, ignorance is bliss this time!  what i mean is, i just used the stock inductor that was in my mates wah when i got it (robbed it from the old pcb)...it's quite long i guess (compared to say, the red fasel) with 3 small prongs at each end and red goop stuck around those prongs and on top.  i dunno what the inductance? readings of it are cos my dmm doesn't do that, unfortunately.     so i just jammed it in there and hoped for the best!  ha!   

[philbinator1]

I've built one once and used half of a RadioShack audio transformer as the inductor.  It worked great although I never got the right pot or treadle enclosure for it.  I ended up using it in my Hystoresis as a filter to tweak out the clicking.  I'm sure the correct inductor would've sounded better.  I actually liked it as is though.  I still go in to pawn shops and thrift stores looking for a non-working wah enclosure.  Which leads me to my next question.  What treadle enclosure are you putting your circuit in?

well it's from my mates wah so back in that so he can use it normally.  i don't think he'd be too interested in the other variation.  so yeah a normal crybaby enclosure.

[philbinator1]

So..seems my celebrations may have been a little premature.     i'm trying to get it in the enclosure but aren't having too much luck.  no true bypass or anything, just the ol' 3-prong wah switch (a SPDT?) with a battery adaptor.  anyone have a diagram handy for a v846?


cheers
phil

[Brymus]

Oh I see now I thought,I  you were building an enclosure for it too.
Thats what makes DIY wahs so hard is getting the treadle mechanism right.
Still congrats to you for sticking with it and getting the result you wanted,now your hooked and there is no going back LOL

[Paul Marossy]

Just for grins, here is the second DIY wah shell I made from scratch. It's was really pretty easy to make, and it worked fairly well - http://www.diyguitarist.com/DIYStompboxes/DIY-Wah2.htm

[philbinator1]

Alright!  The wah is fully functioning, thanks mostly to you guys (esp. Ullyses, thanks man) and some good guesswork regarding
the power supply, ha!  anyway it sounds great and i'm hoping my mate will be happy.  thanks again for the help guys!  roll on the
next project (mxr smart gate...schematic anyone?)!

      

[davent]

Finally!  man i'm pretty please about it, after so many failures.    i used Ulysses' vero V846 and put the circuit together (using 2x 2N3904 trannies instead of the MPSA18's) and then stuck it on the bread board with some jacks and a wah pot.  

http://www.aronnelson.com/gallery/main.php?g2_view=keyalbum.KeywordAlbum&g2_keyword=Vox+V846+Wah+1590B+Vero+Layout+Ulysses&g2_itemId=6509&g2_imageViewsIndex=1

the only thing is, i'm getting very clear radio stations through it...while being kinda funny, my mates' mate won't find it too pleasing.  is this happening because it doesn't have an enclosure yet?  or will i have to make a mod. to it?  cheers guys!

[EDIT]  oh and another thing, it says so put a 100K resistor on the pot but i didn't, not knowing where to put it...anyone know anything about that?

To kill the radio this really helpful page suggests putting a 10-20pf cap between the collector and base of each transistor. http://www.wah-wah.co.uk/index.html  (DIY Resources->Circuit Mods, Volume)

dave

[philbinator1]

To kill the radio this really helpful page suggests putting a 10-20pf cap between the collector and base of each transistor. http://www.wah-wah.co.uk/index.html  (DIY Resources->Circuit Mods, Volume)

dave
[/quote]

Tanks Dave, as it is the enclosure is blocking those...RF?...frequencies, so unless the guy complains about it i'll leave it as is.  After spending a month on
a single pedal you tend to get a bit sick of looking at the same thing     but hey thanks man!  might need that knowledge in the future.   

[Paul Marossy]

After spending a month on a single pedal you tend to get a bit sick of looking at the same thing   

I know that feeling.