The legendary “Volgov” horn, consisting of two tones - high and low - remains the standard of automobile sound signals in the post-Soviet space. Unlike modern single-color tweeters, this electromagnetic the duo is able to cut through dense city noise, warning road users of your maneuver. However, over time, even the highest quality equipment requires intervention: the contacts burn out, the membranes oxidize, and the tonality “floats”, turning a menacing roar into a hoarse croak.
Adjustment GAZ-24, GAZ-21 or more modern GAZ-3110 requires an understanding of the operating principle of the device, which is based on interrupting the circuit with an electromagnet. Incorrect adjustment of the gap or excessive force when tightening the locknut can not only deteriorate the sound, but also completely destroy the mechanism. In this article, we'll take a detailed look at the process of restoring performance and adjusting the tone so that your car can speak with the same confidence again.
Before taking up the tools, it is necessary to carry out an initial diagnosis, since often the problem lies not in the screw setting itself, but in the state of the electrical circuit. If you hear clicks but no sound, or the horn is intermittent, first check contacts for oxidation and integrity of supply wires. Only after making sure that the voltage supply is working properly can you begin the mechanical part of the work.
Design and principle of operation of an electromagnetic signal
The classic Volgov signal is a complex electromechanical system where electrical energy is converted into sound vibrations of a certain frequency. The main design elements are electromagnet, chopper, membrane and resonator bell. When current is applied, the armature of the electromagnet is attracted, opening the contacts of the breaker, after which the circuit is broken, and the armature, under the action of the spring, returns to its original position, closing the contacts again. This cycle is repeated hundreds of times per second, causing the membrane to vibrate.
Dual-tone is achieved by using two separate devices tuned to different frequencies: one producing a high-pitched sound, the other a low-pitched sound. When working simultaneously, they create that very recognizable chord. The most important parameter here is gap between the core and the armature, as well as the tension of the breaker spring, which directly affect the oscillation frequency and volume.
⚠️ Attention: High voltage is created inside the signal housing when the contacts are broken. Be careful when touching exposed parts of a running device to avoid unpleasant, although not fatal, electric shocks.
To understand the processes occurring inside, consider the main components and their functions in the table below:
| Component | Function | Effect on sound |
|---|---|---|
| Electromagnetic coil | Creating a Magnetic Field | The force of attraction of the anchor |
| Membrane | Sound wave generation | Volume and timbre |
| Adjustment screw | Breaker Gap Setting | Frequency and purity of tone |
| Resonator (bell) | Sound amplification | Signal range |
Understanding the role of each element allows for more effective diagnosis. For example, if the horn wheezes, but the voltage is normal, most likely the problem is a deformation of the membrane or an incorrect position of the adjusting screw. If the sound becomes significantly quieter, the spring may have weakened or oxidized. contacts breaker.
Why exactly two signals?
The use of two tones (high and low) allows you to create a complex sound spectrum that the human ear perceives better than a monotonous squeak. This increases the likelihood of being heard in a noisy traffic.
Necessary tools and preparation for work
For high-quality adjustment of the Volga signal, you do not need complex specialized equipment, but the set of tools must be selected correctly so as not to damage the threads and delicate parts of the mechanism. The main tool will be a set of open-end wrenches, preferably with thin profiles, in order to get to the locknuts in hard-to-reach places under the hood.
You will also need screwdrivers (flathead and Phillips), fine sandpaper or a needle file for cleaning the contacts, and possibly solvent or spray to clean the electrical contacts WD-40 or similar. It would be a good idea to have a multimeter on hand to check the voltage at the signal input to rule out problems with the wiring or the button on the steering wheel.
Before starting work, be sure to turn off the power to the car by removing the terminal from the battery. This safety rule cannot be ignored, since accidental shorting of the signal line wires to ground can lead to blown fuses or damage to the steering column switch.
- 🔧 Set of open-end wrenches (sizes 8, 10, 12, 14 mm) for dismantling and adjustment.
- 📏 Feeler gauges for measuring gaps (or a set of files for calibration).
- 🧹 Fine-grained sandpaper and solvent for cleaning contacts.
- 🔌 Multimeter or test lamp to check the circuit.
Preparation of the work area also plays a role: if you plan to remove signals for a detailed inspection, make sure you have a clean rag and a container for storing small parts. Often the fastening bolts rust permanently, so stock up on penetrating lubricant in advance.
When recording signals, mark with a marker which one was high and which low, or where the “high” tone was and where the “low” tone was. This will help maintain correct phasing during installation, although it can be difficult to discern by ear.
Diagnosis of sound signal faults
Before turning the adjusting screws, it is necessary to clearly determine the nature of the malfunction. Symptoms may be different: the signal may be completely silent, work every once in a while, make hoarse sounds, or change tone spontaneously. Each of these signs indicates a specific group of problems within the mechanism or in the external circuit.
If the signal is silent, start by checking the fuse and applying voltage directly to the device terminal. Often the problem lies in the oxidation of the button on the steering wheel or in the violation of the mass of the signal housing on the body. Make sure contact group clean and provides a reliable connection.
A hoarse, intermittent sound most often indicates burning of the breaker contacts or a violation of the geometry of the membrane. In this case, simply adjusting the gap may not help; disassembly and cleaning of the surfaces will be required. If the signal sounds, but is very quiet, check the fastening of the bell and the absence of cracks on the body through which the sound wave can escape.
It is important to distinguish electrical faults from mechanical ones. If, when you press the button, a distinct click is heard, but there is no sound wave, it means that the electromagnet is working, the armature is moving, but there is no consistency in the operation of the breaker or the membrane is damaged. If the silence is deathly quiet, look for a break in the circuit or a burnt out winding.
Step-by-step instructions for adjusting tone and volume
The process of adjusting the Volgov signal itself is based on changing the gap between the opening contacts of the breaker. This gap directly affects the frequency of vibration of the armature and, accordingly, the tonality and purity of the sound. To perform the operation, you will need to find an adjusting screw with a lock nut on the signal housing (usually on the bottom or side, under the protective cap).
First loosen the locknut so that the screw can rotate freely. Then, while applying power to the signal (short presses), slowly rotate the screw. Moving the screw inward (tightening) reduces the gap, which usually improves tonality, but can cause the contacts to stick. Unscrewing the screw increases the gap, reducing the frequency, but may cause the circuit to break and the sound to stop.
Your task is to find the “golden mean” at which the sound will be loudest and clearest, without wheezing or dips. This is a trial and error process that requires patience. Once the optimum sound is achieved, hold the screw in the desired position and carefully tighten the lock nut, being careful not to throw off the tuning.
☑️ Adjustment algorithm
Remember that you need to adjust both signals (high and low) separately, achieving a harmonious sound of the duet. If one of them is not tuned correctly, the overall effect of the "Volgov" chord will be lost and you will get a dissonant noise. After adjustment, check the operation of the signal with the engine running, since the mains voltage can affect the operation of the electromagnet.
⚠️ Attention: Do not tighten the adjusting screw all the way. This will cause the contacts to stop opening, the current will flow constantly, the coil will overheat and burn out, and the membrane may become deformed from overload.
Maintenance of the contact group and membrane
If adjusting the screw does not produce the desired result, or the sound remains hoarse, the interior of the signal may need to be serviced. Over time, the breaker contacts become overgrown with carbon deposits and oxides, which increases resistance and impairs sparking. To clean them, use fine sandpaper or a special file, giving the surface a flat shape.
Pay special attention to the membrane. This is a thin metal petal that should not have cracks, corrosion or signs of deformation. If the membrane is damaged, it cannot be repaired - the entire device must be replaced. Also check the condition of the breaker spring: it should be elastic and free of corrosion, which could change its rigidity.
It is important to maintain cleanliness during assembly and maintenance. The ingress of dust or abrasive particles between the contacts or on the surface of the membrane will lead to rapid failure of the unit. After cleaning the contacts, it is recommended to blow out the mechanism with compressed air.
Lubricate the rubbing parts inside the signal with conventional lubricant (such as Litol or grease) absolutely not recommended. The sticky grease will collect dust and eventually coke, blocking the movement of the armature. If lubrication is necessary, use a minimal amount of graphite lubricant, but it is best to stick to dry cleaning.
Cleaned contacts prolong the life of the signal, but the main thing is to ensure their tight fit and the absence of oxides that create resistance to current.
Typical configuration errors and their consequences
One of the most common mistakes is trying to make the signal as loud as possible by tightening the adjusting screw too much. Beginners think that the smaller the gap, the more powerful the sound. In practice, this leads to the fact that the magnetic field does not have time to subside, the armature “sticks”, and the current in the circuit becomes constant. The result is overheating of the winding and a fire hazard.
Another mistake is ignoring the state of the mass. Trying to adjust the sound, owners turn the screws for hours, although the problem is simply poor contact of the signal housing with the car body. Rust under the mounting bolt creates high resistance, which causes insufficient voltage to reach the coil, and no amount of tone adjustment can help.
Violation of the connection sequence is also common. In two-tone systems, it is important that both signals are powered simultaneously and from a reliable source. Using thin wires or strands instead of soldering can result in voltage drops during peak load when both signals turn on simultaneously.
- 🔥 Overheating of the winding due to direct current (contact sticking).
- 📉 Loss of tone due to membrane or spring corrosion.
- ⚡ Damage to the steering column switch due to a short circuit.
- 🔊 Sound dissonance when a pair of signals is incorrectly configured.
Avoid using “folk” methods, such as tapping the working signal body with a hammer. Although this was sometimes mentioned in old Soviet manuals as a way to "shake up" a stuck anchor, in modern conditions it is more likely to result in a crack in the hull or deformation of the membrane than an actual repair.
Is it possible to install one modern signal instead of two Volgov signals?
Technically it is possible, but you will lose that very recognizable tonality and power. Modern single-tone signals (such as “Diego” or Chinese analogues) often have a higher frequency, but less penetrating power in a noisy stream. In addition, to install one signal, you will need to change the connection diagram and, possibly, install an additional relay, since the standard wiring of GAZ vehicles is designed for parallel connection of two consumers.
Why does the signal start to wheeze in wet weather?
Moisture getting inside the socket or on the contacts changes the mass of the membrane and the conductivity of the air gap. This leads to a change in the resonant frequency and the appearance of wheezing. If this happens regularly, it is worth checking the tightness of the installation or drilling a small drainage hole at the bottom point of the signal housing (if the design allows) so that water does not stagnate inside.
How much current does the Volgov signal consume?
At the moment of switching on, current consumption can reach 8-12 Amps per signal. When two signals operate simultaneously, the load on the network is about 15-20 Amperes. That is why it is important to use wires of sufficient cross-section and working relays, if they are provided for by the design of your car.