Bypass capacitor

should the value of the bypass capacitor be larger, if so how large.

can a ceramic capacitor with 0.01 µF act as a bypass capacitor.

depends on what you want to bypass, and what exactly is doing the bypassing. More details about your application?

take a look at the following mixer circuit in the attachment

my teacher says that the last part [the part that i have boxed] is a filter.

but when i did my practicals i did not get any output in the CRO if those capacitors were present.

the output that i must get is the difference of the two frequencies Fx and Fy.

can it be explained.

The amplitude at the output will depend on the frequency of the circuit and the value of the resistors.

neo_star said:

my teacher says that the last part [the part that i have boxed] is a filter.

Click to expand...

Correct, it is a low-pass filter.

neo_star said:

but when i did my practicals i did not get any output in the CRO if those capacitors were present.

the output that i must get is the difference of the two frequencies Fx and Fy.

Click to expand...

The output of the mixer will contain the frequencies:
Fx, Fy, Fx+Fy, Fx-Fy, and probably many others such as 2Fx-Fy, 2Fy-Fx etc.
The task of the filter is to remove everything except Fx-Fy which will be the lowest frequency in the output of the mixer, hence the use of a low-pass filter.

What you need to consider is, what frequencies were you using in your practicals?
What is the cutoff frequency of the low-pass filter?

JimB

thanks all

I usually use a 47 micro Farad bypass cap while using a SL100 transistor.