Resistor to ground vs a resistor in series ?

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Resistor to ground vs a resistor in series ?

Postby EdRoperL1 » 06 Jan 2013, 04:37

Can somebody explain, to a beginner, what exactly is happening when you have a resistor in a circuit that bleeds to ground vs just passing on in series with rest of the circuit

This is in reference to the sdd-3000 schematic here http://analogguru.an.ohost.de/001/schem ... 00-pre.gif

For example, R4 bleeds to ground, but right after it R6 is in series with positive wire. Why?

What is happening with the electrons when you bleed a signal to ground through a resistor as opposed to having it continue one?
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Re: Resistor to ground vs a resistor in series ?

Postby EdRoperL1 » 06 Jan 2013, 23:01

meow?
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Re: Resistor to ground vs a resistor in series ?

Postby galmar » 02 Sep 2013, 21:30

I don't undestand your question really. "Horizontal" resistors may be needed to form a voltage divider, to limit a current, to form a low-pass filter etc. A resistor to ground may be used again for voltage dividers, to form a high-pass filter, to form a discharging path for caps to ground etc.

There are many uses and I mentioned some basic ones, but I really don't understand what and why you are asking. :)
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Re: Resistor to ground vs a resistor in series ?

Postby commathe » 03 Sep 2013, 06:21

EdRoperL1 wrote:Can somebody explain, to a beginner, what exactly is happening when you have a resistor in a circuit that bleeds to ground vs just passing on in series with rest of the circuit

This is in reference to the sdd-3000 schematic here http://analogguru.an.ohost.de/001/schem ... 00-pre.gif

For example, R4 bleeds to ground, but right after it R6 is in series with positive wire. Why?

What is happening with the electrons when you bleed a signal to ground through a resistor as opposed to having it continue one?
It's not necessarily doing the same thing every time. In the schematic you posted it appears to be a "pull-down" resistor. What it does is it allows C1 to discharge to ground when the effect is switched off. This stops the capacitor charging up while the effect is off and then discharging with a POP when you switch the effect on.

As the poster above posted though, there are a number of different reasons and uses for transistors to ground. R3 in that schematic provides biasing for the op-amp; R4 forms a high-pass filter with C2; R5 provied biasing to the second op-amp; R113 is used in conjuction with C59 to make a high pass filter again.
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Re: Resistor to ground vs a resistor in series ?

Postby DrNomis » 03 Sep 2013, 10:38

EdRoperL1 wrote:Can somebody explain, to a beginner, what exactly is happening when you have a resistor in a circuit that bleeds to ground vs just passing on in series with rest of the circuit

This is in reference to the sdd-3000 schematic here http://analogguru.an.ohost.de/001/schem ... 00-pre.gif

For example, R4 bleeds to ground, but right after it R6 is in series with positive wire. Why?

What is happening with the electrons when you bleed a signal to ground through a resistor as opposed to having it continue one?



R6 looks to me like it's doing at least a couple of things, firstly with the resistor going to ground it forms part of an attenuator to reduce the amount of signal being fed to the op-amp stage, secondly it is working in conjunction with the gain pot on the op-amp stage to set the maximum amount of gain that the op-amp stage can produce when the gain pot is maxxed-out..... :thumbsup
Genius is not all about 99% perspiration, and 1% inspiration - sometimes the solution is staring you right in the face.-Frequencycentral.
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