a strange question I have about signals and systems?

[circuit975]

i salute the whole community

I came across these two while working on signals and systems, what does it mean? I mean, I couldn't figure it out in my head, how are they being used?

 

[rjenkinsgb]

The circle is a "summer" - an op-amp, in essence.

The + and - the signal being added in phase to the output, or (-) being inverted/subtracted from the output.

 

[circuit975]

The circle is a "summer" - an op-amp, in essence.

The + and - the signal being added in phase to the output, or (-) being inverted/subtracted from the output.

I didn't quite understand what you were saying. can you tell me what you are saying through the expressions in the picture?

 

[rjenkinsgb]

Without a context for the diagrams, I don't know what the inputs and outputs are exactly.

The h(t) is just "some function" with a parameter or variable t.

 

[circuit975]

Without a context for the diagrams, I don't know what the inputs and outputs are exactly.

The h(t) is just "some function" with a parameter or variable t.

hmm, let's say ;

v(t)= 5+4cos6n
h(t) = sin8nt/ π.t

so be it.

what are we supposed to do?

 

[danadak]

y(t) = v(t) * h(t) - v(t)


simplify from there.

 

[circuit975]

y(t) = v(t) * h(t) - v(t)


simplify from there.

is this for the one on the right or the one on the left ?

 

[danadak]

The circle is a summer, with two inputs, one + or add, the other - or subtract.

So if I put two signals into a summer with + and - what is the output of the summer ?

Once you understand that you can answer your question. Eg. which summer passes
v(t)*h(t) and subtracts v(t) to produce

y(t) = v(t) * h(t) - v(t)

 

[circuit975]

The circle is a summer, with two inputs, one + or add, the other - or subtract.

So if I put two signals into a summer with + and - what is the output of the summer ?

Once you understand that you can answer your question. Eg. which summer passes
v(t)*h(t) and subtracts v(t) to produce

y(t) = v(t) * h(t) - v(t)

thanks for your reply. but we have a problem, I think you skipped there.

there are differences such as "+" and "-" in the parts I surround with green. i didn't understand how to express y(t) when there are differences here. that's the real problem.

for example, y (t) = v (t) * h (t) - is v (t) for the one on the left or for the one on the right? and why? that's the answer we're really trying to look for.

I'm trying to understand the logic of how our perspective on such charts should be.


I hope everything has been clear and clear this time.

 

[danadak]

I think the summer is an adder, so "+", and the other two polaritys signify
the signal polarity being input to the summer.

So left hand drawing takes h(t)v(t) +[- v(t)] to produce y(t)