Series Diodes: what gives?

[drew.spriggs]

Long story short, I am working on modifications for something and certain knob positions could leave me in a position where I've got a half-wave rectified signal. Logically, I'd expect it to clip half of the waveform off and reduce the other half by the diodes forward voltage, giving a very distorted signal.

Scoped with with a signal generator, and it's not even close to what I'm getting. Half my waveform is getting squished by the forward voltage of the diode (ie. perfect the top half, squished the bottom half by 0.3v (ish) for a Schottky). 1N4007 does the same thing, only minus half a volt or so.

Out of interest, I plugged this into a couple of patch leads and feeding my guitar through it, I get no practical change to the perceived sound of the guitar.

What gives?

 

[Bio77]

What is the difference in p-p signal intensity from your PU vs. the signal generator?

 

[drew.spriggs]

What is the difference in p-p signal intensity from your PU vs. the signal generator?

I have roughly 1.2v p-p from my pickups, and 0.5-3.3v from my signal generator.

 

[Bio77]

I have roughly 1.2v p-p from my pickups, and 0.5-3.3v from my signal generator.

Do you see the clipping with 1V p-p coming out of the the signal generator? Just thought it was acting like a fuzz when you roll off volume.

 

[drew.spriggs]

Do you see the clipping with 1V p-p coming out of the the signal generator? Just thought it was acting like a fuzz when you roll off volume.

With a single diode, I see half the waveform squished by the forward voltage of the diode (using Schottkys), but it conducts in both directions

 

[jwin615]

Nm. I thought after I typed.

 

[drew.spriggs]

Nm. I thought after I typed.

The thought came up (before the edit), but I have tried a blocking cap and no difference.

I built the PCB anyway, so I guess we'll see what it sounds like haha

 

[cdwillis]

Have you tried increasing the signal generator signal to match the bigger signal you'd get from the guitar pickups?