DIY Function (Signal) Generator

Here is my homemade function generator that can produce a square, triangle, and sign wave. This is all done with a few bucks worth of parts. The heart of the function generator is a LM324N quad OpAmp.

Here is a link to the original site, the kit is now discontinued.

[Sarahbuildsstepsequencers]

That is sweet! And I love the little oscilloscope lcd. Nice they don't 'force' you to buy their kit by withholding the schematic and parts list. Seems to work just fine. Thanks for sharing.

[Electronhacks]

It is easy for you to do this type of research, do a search for the IC's name and "Datasheet" (You will need this if you plan to use the IC anyway). It looks like the pin-out is the same, the IC's are similar so since we are making a fairly crude device chances are you can safely substitute the IC's. That however does not mean you will not need to do some experimentation and possibly modify the circuit.

[RuiSantosdotme]

thanks i will try this circuit soon, thanks for the reply!
Good luck with your projects

[RuiSantosdotme]

For the output waves did you use which type of wires?
Coaxial wires?

or just normal wires?
thanks...

if you want your led blinking you can add to the circuit a 555 IC and it will easily blink the led... i hope it helps you

[christopherchang]

This is great work! I'm actually working to try to build a 7400 based function generator but there's a lot of issues I'm running into with the sine wave atleast. I may have to abandon it because your design looks much nicer than mine :)

[uroojabbas]

Please mention the all requirements of this function generator, and also share the circuit diagram of this.

[SophieC]

Hi, built this function generator on breadboard, I managed to get 7.6kHz output. The waveforms are ok at low frequencies, but not too good as you go up the frequency range!

[abramharrison]

I like that enclosure, where is it from?

[Sarahbuildsstepsequencers]

The 4 diodes are a curious thing; maybe their purpose is simply to drop the voltage by about a volt.

[jeetendragacc]

could we buy then pre-assembled? i am not too good at assembly and soldering, and i need a lower range signal generator.(not too expensive)

[TOmaynardOL]

Hey where in the schematic did you add a light for power?

[sunnypiyush]

Would the connections remain the same if i use LM324N instead of LM348?

[moizazeem]

Are you getting 50% Duty Cycle on output?

[octaviansulean]

Could you use a different op amp to have a bigger frequency? Could you tell me if this is posible? to have a frequency range greater than 7000Hz (e.x could it be modified to reach 20MHz) with an quad op-amp ic?

[Electronhacks]

@ElektroHut Nope I have not tried any others, to many other projects to do!

[rflberg]

The diodes clip the triangle wave to make a fake sine wave.

[helgesverre]

If you connect that to a speaker.... would it make sounds?

[Electronhacks]

Coax would be better but a regular wire would work.

[techman]

555 ic kit now days are best for square way and duty cycle and htz

[SkazaTV]

its something wrong if i use polyester capacitors??