Hello.. musician here/circuit noob.

I've mucked about with the 555 quite a lot and am trying to take it a step further.

I've built the HT8950 voice changer before and now I want to do it again, this time cloned with an opamp for filtering and feedback control.

But that is not what my question is about (yet).

I was hoping some of you could help me understand if/how it would be possible to control the pitch up/down function of this chip with a potentiometer instead of pressing buttons?

The datasheet is here: https://www.sparkfun.com/datasheets/Components/General/8950v110.pdf

Its the pins 16 & 17..

I'd like to have a knob to turn, instead of having to press buttons many times, in order to do fast change of pitch. Pressing buttons is clunky.

Any/all ideas are greatly appreciated!

Thanks,
Bob

 

What about a miniature rotary switch.
Max.

 

Hah.. well.. thanks for the obvious answer.

I guess that would do the trick. I just need to know how many steps of pitch shift it does and put in a rotary switch of that many steps.

Using a regular pot would make it smoother, tho.. but trickier to implement.

 

It shows binary 0-7.
BCD switch.
Max.

 

Great idea @MaxHeadRoom!

A rotary BCD switch can directly be wired to SW0, SW1, and SW2, to quickly change the pitch. You’d ignore the high bit output, which would result in the pitch settings being repeated twice over the full rotation.

 

Hello,

That HT chip is only capable of a couple of fixed modulation frequencies.
What kind of sound do you want to have?
If it is the sound like the Daleks of the Dr Who series, have a look at the voice modulators section of the Dalek forum:
https://www.projectdalek.com/

Bertus

 

I guess I should have said an Octal switch!
Max.

 

Hello,

That HT chip is only capable of a couple of fixed modulation frequencies.
What kind of sound do you want to have?
If it is the sound like the Daleks of the Dr Who series, have a look at the voice modulators section of the Dalek forum:
https://www.projectdalek.com/

Bertus

Oh wow. I knew Dr. Who fans were dedicated but that is extreme. I like it and signed up, but awaiting approval.

Thanks

 

Hello,

At the Dalek forum, there is a large group that even build their own Dalek.
You can even download plans for building a Dalek from the several series of Dr Who.
Some even made them with motorized movements of the Dalek.
To have the voice like the Daleks, the voice modulator was developed.

Stated on the Dalek forum:
Remember, at Project Dalek, we are 'hardcore' Dalek builders. We don't 'do' general Doctor Who topics and we don't 'do' Dalek fiction. For us, it's the actual Dalek props that matter.

Bertus