[sdiy] newbee! help!

[Scott Bernardi]

The simple RC filters should be connected like a "voltage divider" (in series), not
in parallel.
Don't know if this ASCII circuit diagram will come out right:

Low Pass:

Vin o---/\/\/\/\/\-----------o   Vout
                            |
                            |
                     -----+-----
                     -----+-----
                            |
                            |
                       ---+----
                          -----
                           ---

High Pass:

                     | |
                     | |
Vin o ---------++----+------o   Vout
                     | |       |
                     | |      <
                               >
                              <
                               >
                               |
                          ----+---


As for the breadboarding, the Radio Shack types work fine.  What are you using for
power supplies? Opamps need power, usually split (+ and -) supplies.  A couple of
9v batteries will work if that's all you have. Make sure you get the polarities
right!



the-h at mail.utexas.edu wrote:

> Hiya synth diyers. I am just starting up with synth diy and have been testing a
> few things on breadboard and am getting some strange results. I first made a
> simple passive high pass filter just a capacitor with a resistor across it. It
> worked fine but then i switched the capacitor and resistor (to make it low
> pass) and it just stopped working, no sound at all. Ive also been trying to do
> some simple stuff (making an inverter or regular amp) with an op amp. and
> meeting with unbrideled failure, they just don't work. I think my main problem
> might be my technique for connecting the 1/4" jacks into the breadboard, or my
> laying out of components on the breadboard. If someone could recommend some
> construction and prototyping techniques it would help a whole lot. I have one
> of those minimal type breadboards, no power or oscilator or nothin (its the
> kind you can get at radio shack). Any help would be great.

--
Scott Bernardi
sbernardi at attbi.com