Green Ringer Waveform

[sta63bmx]

Is this what the Green Ringer is supposed to do?  Bottom trace is the input, top trace is the circuit output.



One note: the input is a 1 kHz sine wave centered about 0 VDC, and the input does look like a 2 kHz something, but the scope's DC ground is about 100 mV BELOW the top peaks of the output waveform.  I used the tonepad layout and 2N5088's from digikey and a 2N3906.  I'm assuming the transistor pinouts are right, didn't check them.  I am getting that goofy cartoony sound higher on the neck and that weird not-really-distortion lower down.  Circuit seems a little quiet.  I'm running of a 9V battery and I haven't checked any voltages in the circuit yet.  I have NO CLUE what the waveforms should look like and I thought "It sounds kinda crappy; maybe I screwed up."  I'm not a huge fan of the circuit.   Is this what the waveforms are supposed to look like?  Thank God for scopes.

I'm sorry to bring this circuit up, but I didn't see any waveforms when I did a search.  I only looked in the first page of results.  I'm so dumb I can't even get my finger out of the way with a tiny camera phone lens.  Makes a nice scope cam, though.  I was surprised by how well the picture turned out!

[bwanasonic]

Just out of curiosity, what were you expecting it to sound like and led you build it? Your description of it sounds like maybe it's working the way it's supposed to, but maybe it needs a little help. It is one of those effects you have to *play*, in the sense that different regions of the guitar produce different effects. Try driving it it with another distortion/fuzz or running it before another distortion/booster. Pickup type will effect the way it responds as well (hot/vintage, HB/SC, active/passive). I like it best as a fuzz/distortion *accessory* than on it's own. The basic characteristics are mild fuzzy distortion in lower registers, octave effects centered around the 12th fret, and some "ring mod-like" effects when multiple strings are sounded ( try playing some bends against held notes, like fretting the high E + B at the 12th fret, while bending the G string at the 14th fret up 1 whole step for some strange sounds). The scope intuitively looks about right to me, but I have no experience with scopes. Tweaking-wise, you can try closely matching the pairs of parts between Q2 and Q3. Search the archives for some more tips on this circuit.

Kerry M

[Processaurus]

That waveform is right.  The DC ground should be about in the middle of the ouptut waveform, so that it isn't passing DC on to the next thing its plugged into.  As for sounding crappy, well, what its doing is rectifying the negative half of your guitar signal to try and create an octave up.  How convincing this octave is another matter, alot of times its just this crazy distortion when it gets complex waveforms, like chords, input to it.  It definately likes the neck pickup, especially with the tone knob turned down, if you haven't tried that yet.  It doesn't have a ton of sustain, though, in any case.  Some other people have commented on boosting the signal before it to help with that problem.  Other octavia designs have more sustain, like the scrambler and Foxx tone machine.  None are as simple and easy as the Green Ringer, though. 

I dont think that the circuit needs fine tuning/tweaking in this case, because the point of matching diodes and their resistors is to get the peaks on the rectified waveform to be even in magnitude, which they are in the picture.

Scopes are sweet.  Thanks for the picture.

[DDD]

The output signal form seems to be right, including scope's "ground" level. Since the output signal is quite asmmetric (high contents of the 2nd and 4th harmonic), the DC level is closer to the "wide" peaks.

[sta63bmx]

Thanks for the replies, guys.  To respond to a couple questions...

Bwanasonic: I just built it out of pure curiosity.   I was also looking for something to "make a weird noise", I guess.  I etched the board in a run of other boards a while back and finally got around to putting it together.  I hadn't listened to any sound clips and I was kind of concerned by the lack of sustain and distortion lower down.  Running a clean guitar into it was probably my reason for the blase reaction to it at first.  I was expecting something cooler on a clean guitar, I guess.  I was running a Yamaha SBG into it, vintage-y humbuckers, around 8-9K.  More distortion lower down, lots of gibberish playing anything over two notes simultaneously, but I got the cartoony sound higher on the neck with the neck pickup.  That was funny.  I will try an overdrive  or clean boost in front of it later today.

Processaurus: You're welcome for the picture.  I thought it looked really cool when that signal was coming out.  Guitar electronics are slowly curing me of my distaste for electronic work.  I'm usually only doing it in the lab when something is broken or I have to get something to work, and that is never enjoyable.  I think I have a prejudiced view of scopes and electronics because of that.  It has been pure enjoyment these last few weeks building something, seeing it work right away, and then being able to hear and see what happens through the circuit.  Putting the waveforms and the sounds together is cool.

DDD: I forgot to consider which way DC ground would be pulled by the waveform itself.  Thanks for mentioning that; it made me think about it a little differently.  I guess you could look at each part of the waveform and find the vertical coordinate of the centroid of that line segment, and then it would be further up there.  I had not considered that at all.  Thanks!

I was bummed that it seemed lame at first, so I got up early this morning to solder before I had to go to work, trying to make up for lost time by populating an Orange Squeezer as the sun came up.  I felt a little better when 7am rolled around , but now that I've gotten more advice on running the circuit, maybe I should have stayed in bed and just given it another shot later before moving on.  I'm sorry, Green Ringer.  Maybe I judged you too quickly.

Ed. Note: Take nothing in my posts seriously.