Hello, I am running through a series of projects from an old digital circuit book I got for almost nothing at a local store.
One, of the things it has me building is essentially a logic board test kit. One of the items to build is a 7404 both 1MHz and 1KHz frequency output using 3 of the 6 hex inverters.
Attached is the picture in the book, bear in mind the book is black and white so picture it that way ignore the red dots you see..



Simply he has a 150ohm resister and a .022uF cap to create a 1KHZ (square?) wave. I'm having the hardest time building this on a breadboard. I have traced it out a million times and I never seem to get it right. I've left out the 3 unused inverters and the VCC and GND connections for the 7404.

No mater what I do I always get a frequency of 60Hz, I can fool around on the Oscilloscope and get it to change but not much maybe up to 100KHZ (I'll be honest I'm trying to learn the oscilloscope, very confused). Should this produce a 1KHz sine wave or a square wave? measure measurements from OUT far right last output of the 3 gates shows up as 60MHZ on my benchtop DMM as well so I don't trust me moving the scope around to get a different value as its true output. Anyways never gotten 1KHZ. Is that right with this circuit?

He shows the same circuit with a 1500uF capacitor given a 1MHZ wave. Presumably using the other half of the 7404 or another together.

Help, I ran this on some online sims and didn't get any values for a frequency, and I got errors.

How would one wire this in a breadboard? Also is there a better more stable way to get 1 KHZ wave with just a resistor, capacitor, and a 7404 chip? I really need help with the breadboard portion.

Apologies I know this is a dumb and easy question for most of you. Take pity on a newbie who literally spent the entire weekend nothing trying to get this to work. I found one diagram online for a different chip 7414 I think, and it looked like what I needed (different values) but the breadboard drawing leaves one end of the resistor unconnected to anything I can't see how that works. I build that circuit regardless and nothing, 60MHZ with a garbled output on the scope. I'm using a ceramic cap does that matter? I notice if I push down on the DuPont wires near the cap or on the cap itself the wave cleans up a bit and almost looks like a PWM square wave still pretty messy...I dunno Im lost. This is driving me mad. I don't want to buy other chips or parts, this should be possible yes? I mean it's literally the beginning of the book. I know there are better chips ect..to pull this off but to start off with I want to see if the circuit is even right. Someone with talent and maybe 5 minutes could wire this up and test it if it gives 1KHz with a square wave take a picture of the bread board, please!!

I did order some 7404's that have a Schmitt trigger, I heard they make this process easier. That's all I know I'll have to research that...

Respectfully,
Anglerfish

 

You post us full of unit errors. The frequency is either 60Hz or 60MHz. You get a MHz range frequency with a 1500uF capacitor (not likely.)

Read through your post and fix all the units.

 

Updated values:

Hello, I am running through a series of projects from an old digital circuit book I got for almost nothing at a local store.
One, of the things it has me building is essentially a logic board test kit. One of the items to build is a 7404 both 1MHz and 1KHz (they are correct the book wants me to make two separate circuits for this frequency, using a combo of 150 ohms and 1500uF to get 1MHz and the one I'm trying first, 150 ohms, with .022uF the picture below changed it to nanofarads automatically to get 1KHz) frequency output using 3 of the 6 hex inverters.
Attached is the picture in the book, bear in mind the book is black and white so picture it that way and ignore the red dots you see.

View attachment 290328

Simply he has a 150ohm resister and a .022uF cap (picture was changed to nF by the software but the book has .022uF) to create a 1KHz (square?) wave. I'm having the hardest time building this on a breadboard. I have traced it out a million times and I never seem to get it right. I've left out the 3 unused inverters and the VCC and GND connections for the 7404.

No matter what I do I always get a frequency of 60 MHz, I can fool around on the Oscilloscope and get it to change but not much maybe up to 100MHz (I'll be honest I'm trying to learn the oscilloscope, very confused). Should this produce a 1KHz sine wave or a square wave? I measure measurements from the far right last output of the 3 gates shows up as 60MHz on my benchtop DMM as well so I don't trust me moving the scope around to get a different value as its true output. Anyways never got 1KHz. Is that right with this circuit?

He shows the same circuit with a 1500uF capacitor given a 1MHz wave. Presumably using the other half of the 7404 or another together.

Help, I ran this on some online sims and didn't get any values for a frequency, and I got errors.

How would one wire this in a breadboard? Also is there a better more stable way to get 1 KHz wave with just a resistor, capacitor, and a 7404 chip? I really need help with the breadboard portion.

Apologies I know this is a dumb and easy question for most of you. Take pity on a newbie who literally spent the entire weekend nothing trying to get this to work. I found one diagram online for a different chip 7414 I think, and it looked like what I needed (different values) but the breadboard drawing leaves one end of the resistor unconnected to anything I can't see how that works. I build that circuit regardless and nothing, 60MHZ with a garbled output on the scope. I'm using a ceramic cap does that matter? I notice if I push down on the DuPont wires near the cap or on the cap itself the wave cleans up a bit and almost looks like a PWM square wave still pretty messy...I dunno Im lost. This is driving me mad. I don't want to buy other chips or parts, this should be possible yes? I mean it's literally the beginning of the book. I know there are better chips ect..to pull this off but to start off with I want to see if the circuit is even right. Someone with talent and maybe 5 minutes could wire this up and test it if it gives 1KHz with a square wave take a picture of the bread board, please!!

I did order some 7404's that have a Schmitt trigger, I heard they make this process easier. That's all I know I'll have to research that...

Respectfully,
Anglerfish

Cleaned up the values, apologies, to simply things further I'm going to take a picture of the book.

 

This is what I am trying to build. Starting off with the bottom 1KHz one.

 

What kind of 7404 gates are these? That makes a difference.

150 Ω is a heavy load for most logic families -- and WAY too heavy for some of them.

You say you are trying to start off with the bottom 1 kHz one, but the bottom one claims to be 100 kHz.

 

That simple circuit can exhibit high frequency oscillations due to its high gain and internal phase-shift.

As asked, exactly what version of the 7404 are you using?
The CMOS 74HC04 will work the best for that circuit, with some added hysteresis to prevent the high frequency oscillation.

 

grr typos...I don't know how to go back and edit posts. Yes, I am doing 100KHz same as the bottom example.

I am using Texas Instruments SN74HC04N -Datasheet from Mouser where I bought them.

 

So I'm confused, look at the book's version of the datasheet (this an old 70's book) and then also look at the name of the chip itself it doesn't say 74HC04 it has LS. So.....how bad did I screw up?

 

There is a menu at the bottom of your post with and "edit" selection.

 

Thank you I see it now. Can't believe I missed that. Sorry guys.

Per Mouser: Input type TTL. Output type CMOS. Propagation Delay Time: 22ns Logic type: Bipolar.
On the 7404's I currently have.

 

74HC04 it has LS. So.....how bad did I screw up?

The picture shows an LS version (low-power Schottky bipolar circuit).
The 74HC04 is a CMOS (MOSFET) version.
They have quite different input and output characteristics, even though they both do the same logic function.

 

So I'm confused, look at the book's version of the datasheet (this an old 70's book) and then also look at the name of the chip itself it doesn't say 74HC04 it has LS. So.....how bad did I screw up?View attachment 290345

74LSxxx and 74HCxxx are different “families” of logic ICs. They use different technologies for the same function. You can Google “difference between LS and HC” to learn about the differences. This is one article that summarizes the differences.

 

Guys I'm new, and I appreciate the help really! Do I have the right chip to make this work? If I have the (low-power Schottky bipolar circuit) version is that a no go? get the CMOS/MOSFET as described above?

 

I would recommend getting the CMOS part that has Schmitt-trigger inputs (I think that's the 74HC14, but verify that).

 

A 7404 is an original 59 years old logic IC that has completely different specs than a newer 74HC04 logic IC.
The 150 ohms resistor is much too low for the 74HC04 IC.
Make a 1kHz audio buzzing oscillator like this:

 

You can make an oscillator with any 74XX04 IC.
You can make an oscillator with a single 74xx14 gate.



If all you have is 74LS04, give me a few minutes and I will show you how to make an oscillator.

In the meantime, even this will oscillate.

 

Guys I'm new, and I appreciate the help really! Do I have the right chip to make this work? If I have the (low-power Schottky bipolar circuit) version is that a no go? get the CMOS/MOSFET as described above?

Maybe… Maybe not. Post a clear close-up photo of your breadboard. And if you have or can get a 74HC04 chip, you can experiment snd see if it works better

 

thank you so much everyone and MrChips I am standing by for your help in creating the two from the book, we can start with the 1KHz and then the 1Hz one. Awesome. I ordered some of the 7414s last night depressed to pay shipping for 2 chips. They won't arrive for awhile.

 

This will work. Experiment with different values of R1 and C1.

 

I ripped out all the cables except for pwr and grnd because I am still trying to figure out how to wire that picture on a breadboard. My brain just doesn't get it. I told you I'm a newb , like newb newb