How to solder a guitar hook. DIY guitar distortion pedal. For questions, contact our group

If you have an electric guitar and a great desire to play rock music, but don’t have an amplifier, then this article will be useful for you! In this article I propose the design of a fairly powerful guitar amplifier with a distortion effect.

The signal from the electric guitar is fed to the input of a two-stage amplifier, which has a high transmission coefficient. Domestic transistors KT3102E were used as transistors VT1 and VT2.
The depth of distortion and the threshold for the onset of the effect are regulated by changing the cascade transmission coefficient with variable resistor R4.

Figure 1 illustrates how this effect works. The dotted line indicates the boundaries of the normal (working) area of ​​the input audio signal. The upper first graph shows the original signal arriving at the input. Let's assume that there are two sections in it where the signal voltage goes beyond the normal range. The second lower graph shows that at the output of a two-stage amplifier, two-way symmetrical limitation of these sections occurs, i.e. "limiting" or "clipping" occurs.

In the initial position of the variable resistor R4, the audio signal will be practically not distorted, while when it is unscrewed, even the average voltage of the input signal from the electric guitar will clip. The sound feels harsher.

After we have obtained the “Distortion” effect, all that remains is to amplify the sound signal. An amplifier assembled on a TDA2030 (or TDA2050) chip will cope with this task perfectly. It is supplied with unipolar power. In order not to overload the amplifier input, the output signal is taken from the collector load of transistor VT2 with a division ratio of 1:27.

Please note that the circuit is powered by 2 Krona batteries with a voltage of 9 V. The first battery (GB1) powers the left side of the circuit, which is responsible for distorting the incoming signal, and the second (GB2) supplies power to the amplifier on the TDA2030 chip. If the voltage is supplied from the power supply, then network interference in the column is possible.

Fig.2. Electrical circuit diagram

Below are photos of the assembly process.
An electrical distribution box was used as the housing.

The variable resistor in my case is like this (not the best choice)

And a small life hack for making a terminal for a “crown” battery from a similar old one. For this device you will need 2 pieces.

You can watch a demonstration of the device in the attached video. In my case, the output sound is heard through a speaker from a music center (speaker parameters 6 Ohm, 50 Watt).

List of radioelements

Designation	Type	Denomination	Quantity	Note	Shop	My notepad
D.A.	Audio amplifier	TDA2030A	1			To notepad
VT1 VT2	bipolar transistor	KT3102EM	2			To notepad
C1, C3	Capacitor	0.22 µF	2			To notepad
C2		10 µF	1			To notepad
C4	Electrolytic capacitor	4.7 µF	1			To notepad
C5	Electrolytic capacitor	22 µF	1			To notepad
C6, C8, C9	Capacitor	0.1 µF	3			To notepad
C7, C10	Electrolytic capacitor	2200 µF	2			To notepad
R1	Resistor	100 kOhm	1			To notepad
R2, R12	Resistor	2.2 kOhm	2			To notepad
R3	Resistor	15 kOhm	1			To notepad
R4	Variable resistor	15 kOhm	1			To notepad
R5	Resistor

I’m not a guitarist, but from time to time I play simple melodies for myself. About 5 years ago, my brother fitted me with an old electric guitar. The guitar was lying idle, but then I came across the book “The 100 Best Radio-Electronic Circuits of DMK Press 2004”, which contained a circuit for the FUS guitar gadget on a dual op-amp LM358. I see the circuit is not complicated, and a breadboard for solderless installation has arrived, you can try to assemble a gadget for a guitar

Fuz lotion diagram for electric guitar

As I said, the lotion is built on a dual op-amp LM358.
The first op-amp contains an amplification stage with clamping diodes at the output; these diodes are needed to convert the sine wave from the guitar into rectangular pulses. The gain is set by variable resistor R13.
The tone control is assembled on the second op-amp; adjustment is made by variable resistor R14

I took the breadboard and started assembling it, putting everything together quickly. I used old slider variables as regulators. I installed only a volume and tone control, I couldn’t find a variable resistor to adjust the gain, so I used fixed resistors 5.1K for the lower threshold, 270K for the middle and 510K for the upper threshold

The power supply for the circuit had to be implemented using a boost converter and a LI-Ion battery from the phone. The frequency of the converter is too high, so the audio range will not be interfered with.
As an amplifier I used a regular speaker with

The first time I turned it on, I was very pleased with the lack of hum in the speakers, although everything was assembled using a layout. After checking everything again, I connected the electric guitar. There was a hum in the speakers, which indicates poor shielding of the cable to the guitar. I tried to play a little, the sound is cool for the first lotion. I tried to record the sound at different positions of the control on the laptop microphone.

As I said before, I'm not a guitarist so don't judge me for my terrible playing.

Performed melodies on this guitar


Guys, if anyone knows what kind of guitar this is, please write in the comments. The only lyrics on the Japan guitar are on the back side.

I’m not going to assemble the gadget into the case yet, the printer doesn’t work, I can’t make it
I ordered a development board from China at this link, a module for increasing the voltage at this link

With uv. Edward

Related materials:

Assemble a guitar gadget. And not just any effects pedal, but a legendary pedal. Jimi Hendrix himself, a brilliant musician and composer, played through this one. Partly this gadget influenced his signature sound. Although we cannot dispute that Jimmy was a genius in his own right, as a genius and a pioneer in many guitar matters.

2016 marks the 50th anniversary of Dunlop's ingenious creation, the Fuzz face. Now you can assemble this pedal yourself.

Here is a diagram where we see one of the typical two-stage amplifier circuits. It is capable of clipping (cutting off the amplitude) of the signal, initially amplifying it and at the same time limiting it with transistors. Unlike distortion or overdrive circuits, where back-to-back diodes are often used to cut the signal. In this case, the clipping level is regulated by a variable resistor included in the feedback.

I would like to draw your attention to the fact that the circuit has a negative mass. Although the original was positive, this will not affect the work in any way. All this is due to standardization and ease of use. The diagram is exactly the same, just drawn differently.

Added: LED indication of switching on, changed the bypass circuit (switching to start the signal bypassing the effect). A 2.2 M resistor has been added. They say it can protect against cracks. A filter capacitor has also been added (you don’t have to install it).
Transistors, since original ones cannot be obtained, can be supplied with MP42b, GT402i.
Having previously selected them by gain.

Here's the PCB.

You can download the printed circuit board in “lay” format here. (downloads: 621)

You can buy the case or make it yourself. For example, bend it from a sheet of metal, or solder it from foil PCB. One advantage is that now we have learned how to make printed circuit boards, and the parts have become smaller compared to old models. The nice thing is that you don’t need to have a huge “frying pan” to place a fairly simple circuit in it.

Here's an example of how you can style your pedal. I would like to emphasize the accuracy of the author of this work. This can be a model for your aspirations. After all, no one wants a sloppy, unattractive lotion. Which is also covered in rosin)). Although the opposite can be said, for example, that beauty does not affect sound. You'd be right.

Thank you all for your attention. Collect beautiful, neat, and most importantly good-sounding pedals.

After all, only when you make a thing with your own hands can you be sure of what you can get from it. And also satisfy your personal cockroaches.

There is a guitar gadget called OCD Fulltone that makes the sound of an electric guitar overloaded to varying degrees. This pedal is considered almost legendary due to its tube sound and wide range of sounds. I have long wanted to buy such a pedal, but the desire was immediately discouraged when I saw the price tag of 9,400 rubles.

But the other day, my friend and I, sitting at work and watching various videos out of boredom, came across a video comparison of the original pedal and a self-propelled gun assembled according to an identical scheme, and for an inexpensive price. And then, as they say, it caught fire. And we are also radio installers, and we were sitting in a room where there are a lot of radio elements, what a coincidence)).

We scratched the surface at work and bought everything we needed. First I had to make a printed circuit board, which was my first time doing it.

Fortunately, the board design was already ready and there was no need to draw anything. I printed it and transferred it to a piece of textolite, previously sanded.

Next is etching. I poisoned it with citric acid, salt and peroxide; everything took about an hour, although it should have taken about five minutes. Most likely I calculated the proportions incorrectly, but the result satisfied me

At work I drilled holes and tinned the board.

We turned it on, checked it and, oh my God! It worked! And even the first time! And it sounds no worse than the original! Well, now all that remains is to make the body.

At first I wanted to make something similar to the original, but I changed my mind, especially since a lucky box came to hand in which I had nails, and I also remembered about craquelure paint, which I had not used for a long time. This is a decorative paint that cracks when it dries. I painted the box with it and placed all the elements

I decided to make the control knobs from sleeves

Well, all that remains is to sign what such a pen does. I painted with paints, I’ll say right away, it didn’t turn out so smoothly, but there’s something in it, I like it)

Just like that. All that remains is to buy a foot power button, although in a radio store it costs twice as much as we spent on this pedal, and we spent about 250 rubles.

For my 50th birthday, I received a Valvetronix VOX-20+ guitar combo amplifier as a gift. A good lamp device with many built-in capabilities. As you master it, you involuntarily replay in your memory everything that you had to play the guitar through on your long musical journey. When I wander around guitar forums and websites, I involuntarily catch myself thinking about how different my generation is from today’s. Sometimes you don’t even understand modern guitar terms: “head”, “cabinet”, “preamp”... In my time it was clearer - amplifier, speaker, preamplifier. For the first time I electrified a string musical instrument, and it was my father’s mandolin, in the 6th grade, installing a piezo pickup on it from a Ural tube radio. At that time I had two radios, Melodiya-M and Ural. But there was no tape recorder. And I really wanted to record something (mainly Voice of America music programs). We had to make something like a phonograph - electromagnetic pickups were then sold for gramophones. If you turn on such a thing at the output of the amplifier, then the steel needle begins to vibrate in time with the sound; all you have to do is lower this needle onto a suitable plastic, and you get a homemade record.

"Ural" and "Melody"

Then my mother and I handed over these two radios and in return they gave us a “Record” radio tape recorder, in which there was a “Nota” tape recorder lamp panel. This thing has already been used 100%. And she wrote the sound, and was my first “overdrive” - when turned on for recording, the set-top box gave a soft overdrive. Modern tube preamps are designed this way. It turns out that we were ahead of our time.

"Nota" and "Rigonda"

My friend A.B. there was a tube radiogram “Rigonda - 101”. When we played music with a port wine at his house, we tuned in through it. In terms of sound, it was in no way inferior to today's small amps. Only we, naive ones, did not understand that this is how it should be turned on, we built all sorts of amplifiers, “boosters”, and gadget pedals. Not everyone knows that Ritchie Blackmore used an old reel-to-reel tape recorder "Aiwa" as a preamp for a very long time (it often catches your eye in concert videos of Deep Purple and Rainbow). Since 1970, a Stratocaster master would connect his guitar directly to the tape input (the tape recorder itself was paused in recording mode) and use it as a preamp to drive his Marshall. "'Aiwa' gives me a fatter sound," says Blackmore. “Without it, the sound is too thin. It's very difficult to play without it. He is a little soul on stage - my little friend.”
Now I’ll make a small review of the circuits of guitar gadgets that were tested at one time. For those who are not in the know, I’ll explain that in order to obtain a viscous, long, thick guitar sound, it is necessary to process it so that the amplitude of the signal is equal for as long as possible. For this purpose, both before and now they use either amplifiers-limiters or pulsed devices - triggers. Now I will show you both.

The first circuit is “Fuzz” - a device based on an amplifier-limiter. (“Fuzz – box” translated as “spray box”). There is nothing incomprehensible here, the amplifier is just an amplifier. The signal is limited in the differential stage on transistors V4 and V5, due to their transition to saturation.

The next two circuits are “Fuzz” - a device based on limiting diodes. This principle turned out to be the most common and is still used today in most branded “Distortion” devices. In the first circuit, an additional transistor V3 is used together with diode switches, in the second, diodes are included in the feedback circuit.

The diodes are included in a slightly different way in the following circuit. This inclusion transforms our “lotion” into a logarithmic amplifier. Maintaining a constant amplitude is smoother here, less "sand" and high harmonics. In today's language we can say that this is no longer “fuzz”, but “overdrive”.

The output signal shape in all three cases is as follows.
There is another way to create a constant amplitude - to convert a sinusoidal signal into a rectangular trigger device. The following scheme implements this.

The sound in this device becomes purely pulsed, “electrocuted”. During pauses there is no signal at all, which is good. What's bad - often these devices are unstable, and grab not the main signal, but some kind of harmonic, creating dissonance. You can play here on a maximum of two strings. The peak of this principle is the repeatedly mentioned “Guitar-Organ” by Ketners, but we will not write about it this time.
The next two circuits are the same limiters, but made on operational amplifiers.

The schemes work very well. The second is a logical continuation and improvement. first. It added another op-amp in the form of a resonant amplifier with adjustable resonance frequency and quality factor. Resistors R8 and R11 allow you to do this quickly during the game. Both schemes are absolutely not critical to the accuracy of the spread of ratings and, if properly assembled, do not need to be tuned.

The next scheme is much more complicated than the previous ones. It is a pulse spectrum converter. The signal here is first amplified by the field-effect transistor V1, then converted to a rectangular one in the op-amp A1, then the signal frequency doubles on the transistor V2, goes back to the Schmitt trigger on D1, after which it is divided by two frequency dividers into "two" and "four". The ability to mix all these signals at the output allows you to implement the principle of register timbre synthesis. (as in EMR)

The prefix, the circuit of which is shown above, combines two devices: "distortion" and "booster". The transition is carried out by a multi-position switch. In other respects, the scheme resembles the first one under consideration.

The last thing I will show you is the “distortion”, which was also the last thing I made. This design is alive and functional. I like her the most. The circuit contains a frequency doubler for A1.3, A1.4, V2, V3. The sound duration control, or “GAIN” as it stands now, is on resistor R9. Any n-p-n silicon low-noise transistors can be used. When using the K198NT1B microassembly (can be replaced with K198NT1A), the differential pair of transistors contained in it should be used in the doubler. The adjustment comes down to selecting a resistor voltage at the emitter of transistor A1.1 equal to 4 V and minimizing the noise introduced by the doubler, resistor R17. To obtain symmetry of the limitation, it is possible to select resistor R23.

And the last thing for today - as a bonus - is a booster circuit for a bass guitar. A very good and simple scheme, makes the sound very expressive. I liked this circuit so much that, having changed the value of capacitor C4, placing several different capacitances through the switch, I installed such an attachment in my homemade guitar, obtaining a set of fixed tones.
I hope that the above fundamental principles will be useful to someone. There are requests on the Internet for the publication of similar schemes. They were taken from the “Radio” magazines and the collections “To Help the Radio Amateur” for different years of the last century.
Photos from the site were used