Dec 6, 2010 · An LM324, by itself, is not a VCO; you have to add the JFet to make a VCO. An LM324, by itself, cannot drive a speaker; you will need an audio power amplifier, like an LM386 to do that.

Mar 10, 2025 · A pcb made according to the schematic (attached below) uses LM324 opamps. With no input signal to the current transformer pin 3 should be low, and pin 2 follows feedback from output pin 1 (high). Two of the opamps give 0.0V on their pin 1, but two opamps measure approx. 2.5V on their outputs...

May 25, 2010 · So what are the big differences/similarities between LM324 and LF347 Op-amps? I just want to understand them a bit more, and it would be great if someone can help.

Feb 10, 2009 · I admit that this thread title is just to get attention and suggestions from Audioguru, that hates LM324. :) I too hate LM324 but ... but it was a nice device at its times. A lot of years has been passed and now I think we have much better devices so I …

Aug 29, 2011 · i have downloaded LM324_unisym_test from yahoo groups **broken link removed**, and it is .asc file, when i click the icon it opens itself in LT spice and says "LM324 from National Semiconductor The LM324 is used with the universal symbol "opamp2" from the standard LTSPICE [Opamps] menue...

May 1, 2008 · Use the LM339 or LM311 as a comparator rather than the LM324 which is a low-power low-speed op-amp not a comparator.

May 22, 2011 · I've mostly worked with digital stuff, but I recently got one of Forrest Mim's books with op-amp circuits and constructed the "Sine Wave Oscillator" using an LM324 instead of an LM741.

May 4, 2019 · I checked the power supply for oscillations using the attached schematic for generating a square wave signal. I used as a load a 4.7R resistor rated at 5W. I used 1N4007 instead of HER508, and I used 3v3 zener diode instead of 13V zeneer diode. The resistor Imin, was modified from 300R to 10R and the Umax resistor was modified to 12K. The transformer …

Mar 25, 2006 · The LM324 is the industry's first "low power" opamp so they made the output transistors without bias current. Therefore they produce horrible crossover distortion with audio signals unless you bias an output transistor with a DC load as a class-A amplifier.

Feb 12, 2025 · The LM324 is an opamp, with a totem-pole output, which will override the timing resistor (s) connected at its output. You need to replace it with a LM339 which does have an open collector output. But then it cannot source current. Your best bet is to split the circuit with a dual comparator and a dual opamp LM393 LM358 respectively.