jghfslk wrote
Is my knowledge correct with the following: no signal when grounded, quieter signal through resistors (larger value=more volume drop), not a lot of change through capacitors
Unfortunately, the answer to your question isn't a simple yes or no. Everything depends on the circuit topology. The connections of components near the resistors and caps in question affects what they do to the signal. The simplest way to start is to read up on
voltage dividers. (Don't stop with the link, do some googling once you understand how the concept relates to frequency-dependent components like capacitors and inductors.) The very oversimplified answer to your question is that signal will drop according to the voltage divider equations, but you must be very careful to account for all impedances that are involved in the voltage divider.
So, correct (no signal when grounded), indeterminate (signal won't drop across resistors that have no path to ground, but will drop in across resistors that are arranged as voltage dividers), and indeterminate (the answer for caps is the same as the answer for resistors, except that now it's frequency-dependent).
I noticed that my signal was significantly quieter (pretty much nonexistent) when I got to the top row (4n7 cap and 1k and 100k resistor). When looking at the schematic, the only thing that goes to ground is the 1k resistor but that is the other side of the resistor. This shouldn't cause me to lose signal though, should it?
Find the junction of the 100k, the 1k, and the 4n7 on the schematic and look for a voltage divider. Do the voltage divider math on the resistors, and figure out how much the signal should drop across the 100k.
Ignore the 4n7 for now, it's a coupling cap for removing DC from the brick input. It's not part of the 100k/1k voltage divider. (It
is part of a voltage divider, but it's a hidden voltage divider involving the input impedance of the brick.) The 100n
does play a part in the 100k/1k divider, but you can ignore it for now. When you're ready, read up on
electrical reactance and see if you can figure out how to include that cap in the equation, for extra credit.
Repeat this out loud ten times everyday for the next week: Everything useful is a voltage divider.*
When you're ready to explore some other basic topics,
read this thread and start googling some of what you read.
I get more confused on ic chips. Should I have signal at all of the inputs and outputs or not necessarily?
Short answer: no. Where you see signal depends very much on both the circuit and the layout. Some layouts include unused op-amps that don't carry any signal at all. Also not all op-amps are used for voltage gain (some aren't even in the signal path), and not all IC's are op-amps. Most IC's will have connections for positive and negative power rails, and those pins won't carry any signal either. Figure out voltage dividers first, then work your way up to op-amps, then start thinking about other types of IC's.
*This is a quote from somebody at diysb. I'm not sure who said it originally, but it wasn't me.
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