So how about this neat little circuit?

cream123

cream123

JustAskinologist
So I'm wondering if I'm reading this right.
PBX2.gif


the signal is series with the capacitor (this is where I become confused) and then it becomes parallel with the 2 resistors? But where does it rejoin? Or is it still in series with the resistor because it has no choice but to go to them? Is it missing a piece from the whole scheme of things? Or I am just missing a piece? :laugh2:

And here's my mods to it for it to be true bypass. I got the info off of this site.

PBX22.gif


Is it right? If not at least it's beautiful :laugh2:

BTW those ugly boxes are as follows: input on left, output on right.
 
Re: So how about this neat little circuit?

I always thought True Bypassed required a 3PDT, or is that only if you want an LED?
 
Re: So how about this neat little circuit?

I think that your switch is correct (but I wouldn't start soldering until Artietoo, or one of the gurus gives their opinion):bowdown:

What does the circuit do? Is it some type of boost? (I'm guessing here).

Quote "......at least it is beautiful" :smack: ...your not considering a career in schematics or fine art appreciation, are you ? ...just kidding bro... beauty is in the eyes of the beholder. Looks cool to me.

Are you building this circuit?

I really respect you determination...like a rotweiller (sp?) chewing a bone

Please take my comments in fun. I admire what you are trying to achieve.

Dave
 
Re: So how about this neat little circuit?

How about this design for an LED? I'm sure it has some effect on the circuit so if you guys could inform me that would be great
PBX23PDT.gif
 
Re: So how about this neat little circuit?

greco said:
I think that your switch is correct (but I wouldn't start soldering until Artietoo, or one of the gurus gives their opinion):bowdown:

What does the circuit do? Is it some type of boost? (I'm guessing here).

Quote "......at least it is beautiful" :smack: ...your not considering a career in schematics or fine art appreciation, are you ? ...just kidding bro... beauty is in the eyes of the beholder. Looks cool to me.

Are you building this circuit?

I really respect you determination...like a rotweiller (sp?) chewing a bone

Please take my comments in fun. I admire what you are trying to achieve.

Dave
Click to expand...

I'm trying to get this stuff down...I was joking I did that in paint. Pretty funny comment though.

It is a boost with a germanium transistor only the transistor is flipped around. It's supposed to get a really weird dist when sent into clipping. :D

I don't have the components yet but I'm thinking about this as a good first circuit. ;)
 
Re: So how about this neat little circuit?

cream123 said:
So I'm wondering if I'm reading this right.
PBX2.gif


the signal is series with the capacitor (this is where I become confused) and then it becomes parallel with the 2 resistors? But where does it rejoin? Or is it still in series with the resistor because it has no choice but to go to them? Is it missing a piece from the whole scheme of things? Or I am just missing a piece? :laugh2:

----------------------------------------------

The input signal is actually parallel to capacitor C1 (used for DC blocking...sorry:13:), R2, and ground. The C1 cap and R2 are in series with each other. The tip of your guitar's cord is one leg of the signal path starting at the capacitor...the other leg of the parallel circuit is the outer barrel of the guitar's cord plug. It is connected at ground (the ground symbol is missing, but is assumed).

The paths of the ground are considered "common" across the circuit. It is the work if the circuit that amplifies, AND isolates the input from the output.

If one wanted to, you could just as well draw a pickup into the circuit, by drawing a coil of wire. One end would be attached to the C1 capacitor, the other to be attached to a ground symbol.
Click to expand...
 
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Re: So how about this neat little circuit?

Sludgenutz said:
The input signal is actually parallel to capacitor C1 (used for DC blocking...sorry:13:). the tip of your guitar's cord is one leg of the signal path starting at the capacitor...the other leg of the parallel circuit is the outer barrel of the guitar's cord plug. It is connected at ground (the ground symbol is missing, but is assumed).

The paths of the ground are considered "common" across the circuit. It is the work if the circuit that amplifies, AND isolates the input from the output.
Click to expand...

I got ya. That makes sense.
 
Re: So how about this neat little circuit?

cream123 said:
So I'm wondering if I'm reading this right.
PBX2.gif


the signal is series with the capacitor (this is where I become confused) and then it becomes parallel with the 2 resistors? But where does it rejoin? Or is it still in series with the resistor because it has no choice but to go to them? Is it missing a piece from the whole scheme of things? Or I am just missing a piece?
Click to expand...

This isn't the type of circuit that you really want to analyze in terms of series or parallel. You just need to understand the functional blocks.

R3, Q1 and R4 form a class A amplifier. To be class A, it needs to be biased to a DC voltage level. R1 and R2 perform that function. Since we now have a DC voltage at our input, (4.9 volts - assuming 9-volt power), we need to block that from going back out the input jack. Thats what C1 does. Furthermore, since our amplified output is riding on a DC voltage, we need to block that from going out the output jack. Thats what C2 does. The volume control is simply that - a voltage divider that controls how much voltage (AC) that makes it out.

Btw - Your bypass in the first drawing is ok. When you add the LED, its wrong. Give me a sec . . . :)
 
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Re: So how about this neat little circuit?

This should be right:

cream01.png


Those two parts of the switch are connected together. They're shown separate for clarity. Also, I believe those "V-" should be V+.
 
Re: So how about this neat little circuit?

Well, Artie's got it all right here. As far as signal flow, it enters the cap C1, which blocks DC of the circuit from getting to the input, then enters the base of the transistor, gets amplified and comes out the emitter, then through C2, another DC blocking cap, and to the output. Resistors R1 through R4 set up the operating point and bias, as Artie has explained, and the VOL pot controls the level. The cap quality is crucial because the entire signal is passing through two of them - a good quality film cap will help here. This very basic circuit would be considered a common collector amplifier.

Noth
 
Re: So how about this neat little circuit?

So would it be possible to turn this into a mild dist. circuit? Or are these 2 different beasts? What if you add more gain stages/transistors? Would this do it? I know the answer is no but I'm tryin to grasp what makes it gainy.
 
Re: So how about this neat little circuit?

cream123 said:
So would it be possible to turn this into a mild dist. circuit? Or are these 2 different beasts? What if you add more gain stages/transistors? Would this do it? I know the answer is no but I'm tryin to grasp what makes it gainy.
Click to expand...

Sure. A distortion circuit is just an overdriven amp stage. If I were you, I'd look over this site, or others like it. I doubt that even I would try to design my own circuit. There's too many proven designs out there.

cream123 said:
What does VR mean on a circuit?
Click to expand...

I'd have to see it in context, but generally, it means "voltage regulator". Someone might also use it to abbreviate "variable resistor", as in a pot. VR can also designate a zener diode, which is used as a voltage regulator.
 
Re: So how about this neat little circuit?

How would you do a gain control? Just a pot attached to a resistor between two p-n-p transistors. Or would need a j-fet or something like that? I'm just piddling around right now.
 
Re: So how about this neat little circuit?

You would add another stage and put a volume control on it. The "gain" of the transistor is a fixed by its construction technique. You increase percieved gain by controlling the volume of additional stages. You would set the volume between a resistor or two such that with the volume all the way "down" you'ld have unity gain. (No gain at all as opposed to "off".) Then as you increased the volume, you'ld increase the percieved gain.

The other way, is by controlling the amount of negative feedback in a more complex amplifier circuit. But thats beyond the scope of this thread. :)
 
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