Pulse generators are devices that are capable of creating waves of a certain shape. The clock frequency in this case depends on many factors. The main purpose of the generators is considered to be the synchronization of processes in electrical appliances. Thus, the user has the ability to customize various digital technology.
An example is the clock, as well as timers. The main element of this type of device is considered to be an adapter. Additionally, capacitors and resistors along with diodes are installed in the generators. The main parameters of the devices include the indicator of the excitation of oscillations and negative resistance.
Inverters
You can make a pulse generator yourself with inverters at home. For this, the adapter will require a non-condenser type. Field resistors are best used. The momentum transfer parameter is at a rather high level. Capacitors to the device must be selected based on the power of the adapter. If its output voltage is 2 V, then the minimum capacitance of the capacitor should be at 4 pF. Additionally, it is important to monitor the negative resistance parameter. On average, it must fluctuate around 8 ohms.
Rectangular pulse model with regulator
Today, a rectangular pulse generator with regulators is quite common. In order for the user to be able to adjust the maximum frequency of the device, it is necessary to use a modulator. On the market, manufacturers they are presented with a rotary and push-button type. In this case, it is best to dwell on the first option. All this will allow more fine-tuning and not be afraid for a failure in the system.
The modulator is installed in the square-wave generator directly on the adapter. In this case, the soldering must be done very carefully. First of all, you should clean all the contacts well. If we consider non-capacitor adapters, then their outputs are on the upper side. Additionally, there are analog adapters, which are often available with a protective cover. In this situation, it must be deleted.
In order for the device to have high bandwidth, it is necessary to install resistors in pairs. The oscillation excitation parameter in this case must be at the level of 4 ms. As the main problem, the square-wave generator (the diagram is shown below) has a sharp increase in operating temperature. In this case, check the negative resistance of the non-condensing adapter.
Overlap Pulse Generator
To make a pulse generator with your own hands, the adapter is best used in analog form. Regulators are not necessary in this case. This is due to the fact that the level of negative resistance can exceed 5 ohms. As a result, a rather large load is placed on the resistors. Capacitors for the device are selected with a capacity of at least 4 ohms. In turn, the adapter is connected to them only by output contacts. As the main problem, the pulse generator has an asymmetry of oscillations that occurs due to overloading of resistors.
Symmetrical Pulse Device
To make a simple pulse generator of this type is possible only with the use of inverters. The adapter in this situation is best to choose an analog type. It costs on the market much less than a non-condenser modification. Additionally, it is important to pay attention to the type of resistors. Many experts for the generator are advised to select quartz models. However, their bandwidth is quite low. As a result, the oscillation excitation parameter will never exceed 4 ms. Plus, the risk of adapter overheating is added.
Given all of the above, it is more advisable to use field resistors. The throughput in this case will depend on their location on the board. If you choose the option when they are installed in front of the adapter, in this case, the excitation excitation rate can reach 5 ms. In a nasty situation, good results can not be expected. You can check the pulse generator for performance by simply connecting the power supply to 20 V. As a result, the level of negative resistance must be in the region of 3 Ohms.
To minimize the risk of overheating, it is additionally important to use only capacitive capacitors. The regulator can be installed in such a device. If we consider rotary modifications, then as an option a modulator of the PPR2 series is suitable. According to its characteristics, it is quite reliable today.
Trigger generator
A trigger is a device that is responsible for transmitting a signal. Today they are sold unidirectional or bidirectional. For the generator, only the first option is suitable. The above item is installed near the adapter. In this case, the soldering should be done only after a thorough cleaning of all contacts.
Directly, the adapter can even choose an analog type. The load in this case will be small, and the level of negative resistance with a successful assembly will not exceed 5 ohms. The parameter of excitation of oscillations with a trigger is on average 5 ms. The main problem with the pulse generator is: increased sensitivity. As a result, these devices are not capable of working with a power supply unit above 20 V.
How to make an overload generator ?
Let's pay attention to microcircuits. Pulse generators of this type imply the use of a powerful inductor. Additionally, only an analog adapter should be selected. In this case, it is necessary to achieve high system throughput. For this, capacitors are used only capacitive type. At a minimum, they must be able to withstand negative resistance at 5 ohms.
Resistors for the device are very diverse. If you choose their closed type, it is necessary to provide for them a separate contact. If we nevertheless dwell on field resistors, then the phase change in this case will occur for a rather long time. Thyristors for such devices are almost useless.
Models with quartz stabilization
The pulse generator circuit of this type provides for the use of only a non-capacitor adapter. All this is necessary so that the rate of excitation of oscillations is at least 4 ms. All this will also reduce thermal losses. Capacitors for the device are selected based on the level of negative resistance. Additionally, you must consider the type of power supply. If we consider pulsed models, then their output current level is on average around 30 V. All this can ultimately lead to overheating of the capacitors.
To avoid such problems, many experts advise installing zener diodes. They are soldered directly to the adapter. To do this, clean all the contacts and check the cathode voltage. Auxiliary adapters for such generators are also used. In this situation, they play the role of a switched transceiver. As a result, the oscillation excitation parameter rises to 6 ms.
Generators with capacitors PP2
A high-voltage pulse generator with capacitors of this type is quite simple. In the market, finding elements for such devices is not a problem. However, it is important to choose a high-quality chip. Many for this purpose acquire multi-channel modifications. However, they are quite expensive in the store compared to conventional types.
Transistors for generators are most suitable for single-junction. In this case, the negative resistance parameter should not exceed 7 ohms. In such a situation, one can hope for the stability of the system. To increase the sensitivity of the device, many advise using zener diodes. At the same time, triggers are used extremely rarely. This is due to the fact that the throughput of the model is significantly reduced. The main problem of capacitors is considered to be the amplification of the limiting frequency.
As a result, the phase change occurs by a large margin. To set up the process properly, you must first configure the adapter. If the level of negative resistance is at around 5 ohms, then the limit frequency of the device should be approximately 40 Hz. As a result, the load from the resistors is removed.
Models with PP5 Capacitors
A high-voltage pulse generator with the indicated capacitors can be found quite often. At the same time, it is able to be used even with power supplies of 15 V. Its throughput depends on the type of adapter. In this case, it is important to determine the resistors. If you select field models, then it is more expedient to install the adapter of the non-condenser type. In this case, the negative resistance parameter will be in the region of 3 ohms.
Zener diodes in this case are used quite often. This is due to a sharp decrease in the limit frequency level. In order to align it, the zener diodes fit perfectly. They are installed, as a rule, near the exit port. In turn, resistors are best soldered near the adapter. The rate of vibrational excitation depends on the capacitance of the capacitors. Considering models at 3 pF, we note that the above parameter will never exceed 6 ms.
The main problems of the generator
The main problem of devices with PP5 capacitors is considered to be increased sensitivity. At the same time, thermal indicators are also at a low level. Due to this, there is often a need to use a trigger. However, in this case, it is still necessary to measure the output voltage index. If at a block of 20 V it exceeds 15 V, then the trigger can significantly improve the system.
Devices on MKM25 regulators
The pulse generator circuit with this controller includes only closed-type resistors. At the same time, even PPR1 series chips can be used. In this case, only two capacitors are required. The level of negative resistance directly depends on the conductivity of the elements. If the capacitance of the capacitors is less than 4 pF, then the negative resistance can increase even up to 5 ohms.
To solve this problem, it is necessary to use zener diodes. The controller in this case is installed on the pulse generator near the analog adapter. The output contacts must be carefully cleaned. You should also check the threshold voltage of the cathode itself. If it exceeds 5 V, then an adjustable pulse generator can be connected to two contacts.