Sallen Key Low Pass Filter, bandpass filter

[Maglatron]

yep 10k both

 

[bertus]

hello,

what is the voltage in the middle of the two resistors?

bertus

 

[Maglatron]

I'll check next session, thanks

 

[Maglatron]

thinking about starting over all colour coded

 

[bertus]

hello,

the voltage should be on the + input of the opamp:


bertus

 

[Maglatron]

ok from the centre of the resistors and GND, got it!

 

[danadak]

I have not read this entire thread but hanging 10 uF and 100 uF on
the output to ground I would think ill advised due to stability issues.....



Regards, Dana.

 

[Maglatron]

got new proto board going to make a start on the circuit from the beggining with colour coded wires and thats the (mic to pre-amp, amp, and REF GND circuit and then the filters and buffer) hopefully get the right results this time

 

[Maglatron]

is this be right? included original so that you can edit if wrong!

 

[Maglatron]

ref gnd circuit too!

 

[Maglatron]

need help with this one, I think like this

 

[Maglatron]

and the final circuit in the light board project!

 

[Maglatron]

so are the scematics in the above posts good enough?? thanks

 

[Maglatron]

I have not read this entire thread but hanging 10 uF and 100 uF on
the output to ground I would think ill advised due to stability issues.....

View attachment 63188

Regards, Dana.

I don't get why but curious as to what you might do?

 

[Maglatron]

so are the scematics in the above posts good enough?? thanks

anyone??? thanks

 

[bertus]

Hello,

Yes, if you follow those colors, you will have more overview over the signals.

Bertus

 

[Maglatron]

I'll get to work asap, thanks

 

[Maglatron]

got a box pack of caps, can I use the electrolytic 100nF instead of the film ones?

 

[bertus]

Hello,

Are you sure that the 100 nF capacitors are electrolytic?
If they are electolytic, I would not use them in the filters, but only for decoupling the power supplies.

Bertus

 

[Maglatron]

no the the 100nf caps I'm using are film type but I was just saying that I have electrolytic ones in the box I bought I do remember you saying that the 10uF ones on the REF GND circuit would be fine though!