Orange treble/bass boost build and ?

[Wild Zebra]

   Hi, I build this pedal last night http://aronnelson.com/gallery/album18/orange_tb_boost.  Low parts count, tiny stripboard, and pretty simple.  How's it sound you ask?  Pretty good.  Its very rangemasterish with basically a tone control.  For those of you who always feel the RM has too much treble.  My question is it calls for an AC-128 or similiar and I had a few of those newer heatsink types(thanks hairyandy).  Well everyone I put in would pass the signal.  I could hear it, but barely.  Nomatter which way I put it in. Highest HFE  was maybe 129, 132 I think.  Well then I put a 2n3904 and it cranked right up.  Very audible boost and piercing highs to muddy lows.  Any Ideas?

All in all its a nice simple build and its sounds pretty good(to my ear) with the 2n3904.

thanks for the layout Dragonfly

[lowstar]

hi there,
have you paid attention to the fact that it is a positive ground circuit ?
just a quick hipshot at this since you say it works with a 3904 which is npn ?!?
so maybe you have the bat reversed ?

cheers,
lowstar

[nelson]

If that is dragonflys layout, there is a mistake in it. It is wired for negative ground. When its a positive ground circuit.

Change the +9v connection to -9v, and change the polarisation of the electrolytic cap. Then your AC128's will work.

[MartyMart]

If that is dragonflys layout, there is a mistake in it. It is wired for negative ground. When its a positive ground circuit.

Change the +9v connection to -9v, and change the polarisation of the electrolytic cap. Then your AC128's will work.

Nope, that link goes to Dragonfly's circuit and it is indeed "positive ground"
-9v to collector and +9 at the ground points !!

Marty.

[nelson]

If that is dragonflys layout, there is a mistake in it. It is wired for negative ground. When its a positive ground circuit.

Change the +9v connection to -9v, and change the polarisation of the electrolytic cap. Then your AC128's will work.

Nope, that link goes to Dragonfly's circuit and it is indeed "positive ground"
-9v to collector and +9 at the ground points !!

Marty.

I pm'ed him about the grounding error last week, it has just recently been changed. Wild Zebra may be working off the old version.

[Wild Zebra]

  Thanks guys, I'll check tonight.  I'm almost positive the link is the same as the layout I used.  I can remember the electro + pointing
downward towards ground, but as lowstar points out its working with the 3904.  Maybe I didn't change my battery wires though, out of habit.

thanks take care