Bobtavia?

[Aharon]

What I found with the Bobtavia is that the chip is really inconsistent,I don't know if the design does not have enough gain or some chips don't cut it.
The good thing about the Neo is that if you put a sw to bypass the transformer and diodes you got a nice booster.
Aharon

[RLBJR65]

oops, sorry! 220uf was not only on the wrong pin but the polarity was reversed as well Layout has been corrected.


Did you catch the polarity problem with 220uF? Because it should have plenty of gain and lots of good fuzzy octave when it's cranked. The octave cleans up as you lower the gain pot,  it's never pristine though.

The last one I built I tried several different 386's in. An LM386 from Rat Shack, LM386 I got from SmallBear and a JRC386 scavanged from an old computer sound card. They all sounded pretty much the same to me.

You can make it an OD to. http://aronnelson.com/gallery/albums/Bobtavia/Bobtavia_OD.gif
The way I have it drawn works but has a slight vol. drop. You could use a DPDT from 220uF cap to level pot that would switch in / out the transformer and diodes. Either way its not a clean OD.

Richard

[KerryF]

Yea, I noticed the whole capacitor polarity and wrong placing.  I corrected it though when I was troubleshooting.  I went to Radio Shack, and exchanged the transformer for a new one (in case I blew it), and also bought a new LM386 and sockets to change them.  I will let you know in a bit when I finish it.

[RLBJR65]

One more thing, forgot to add the jumper wire from strip 7 to strip 9. So ground would be strip 7. Didn't notice until I opened it up.

[KerryF]

^- Yea I was wondering that and I was REALLY confused.  Thanks for clearing it all up 

[KerryF]

Ok, so finally got it finished and working!  The problem was the missing jumper to ground and stuff.  Well I added some features.  I put an LDR for the only resistor in the circuit (100k), but also put a switch to go from the LDR (foot control) and the 100k resistor (standard).  I have a footswitch.  I will have a power switch, LED, and an adaptor jack tomarrow.  I will box it up tomarrow too.

Heres pictures:







I will have sound clips/video clips tomarrow (its late here and I have been working on this pedal for AT LEAST 5 hours!).  It looks simple and all, but after a while of complications, testing and thinking and everything, it adds up in time.  Its working great.  It does give a bit of drive and sounds great with a fuzz before it.

Heres some tone setting descriptions:  (G-Guitar P-Pedal)
Thin, aparent octave: G Volume-10  G Tone-0  P Gain-10  P Volume-10
Octave with crunch: G Volume-10  G Tone-10  P Gain-10  P Volume-10
Clean octave: G Volume-3  G Tone-10  P Gain-10  P Volume-10 (Single Coil/Neck Humbucker)

Let me know what you all think! 
Kerry

[RLBJR65]

Nice job! Sorry about that missing jump.

What effect does the LDR have?

[KerryF]

Thanks for the schematic and layout you posted.  I was wondering when I was going through the schematic because there were a bunch of things going to ground, and then on the layout, they were connected but not at ground.  Glad I figured that out and its working.

The LDR is sortof a volume/dirty control.  The closer you get, the louder (or maybe the other way around), but it also smooths out the tone or dirties it up.  By this I mean, one way its smoother like, and the other is more like if you were to give a fuzz pedal less volts than it needs.  I guess its like a dying battery simulator because it is connected to +9v.

Sound clips later!

[petemoore]

  Cool, if you're still making a clip, please hit and sustain a one or two notes, with the LDR light to dark, dark to light to tell if it emphasizes or counteracts with the high to low input levels of note/s hit hard to sustain tapering.
  Did you measure or *mess with the light to dark resistance of the LDR? [*using resistors parallel or series with the LDR

[KerryF]

I am going to make the clip later today, and will make sure to show every possible thing it can do.  I am mounting it and adding all the stuff (offboard stuff) and I will show all later.  I didnt test with a resistor in parallel because I think the range it has is good for this.

[KerryF]

Ok finished!  Heres the final pictures!  I layed out the box a bit different than a usual pedal, but its cool and all.  The switch all the way on the left, on the top of the box is for Original and LDR Footcontrolled Options.







Sorry about the sound clip delay.  It will be there soon.  This took a bit longer than expected with some things on here and all. 

Kerry

[petemoore]

  Big Bob...

[KerryF]

 

Now sound clip!:
1. Long Demo of just random stuff. Im not demonstrating my playing at all (horrible playing), but the pedal: http://media.putfile.com/Bobtavia-Demo

I had another clip, but it didnt record for some reason so I guess more later.