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 generators is considered to be the synchronization of processes in electrical appliances. Thus, the user has the opportunity to configure various digital equipment.
An example would be clocks and timers. The main element of devices of this type is considered to be an adapter. Additionally, capacitors and resistors are installed in the generators along with diodes. The main parameters of the devices include the index of oscillation excitation and negative resistance.
Generators with inverters
You can make a pulse generator with your own hands with inverters at home. This adapter will require a capacitorless type. Resistors are best used precisely field. Their momentum transfer parameter is at a fairly high level. Capacitors to the device must be selected based on poweradapter. If its output voltage is 2 V, then the minimum capacitance of the capacitor should be at the level of 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 square-wave generator with regulators is quite common. In order for the user to be able to adjust the limiting frequency of the device, it is necessary to use a modulator. On the market, they are presented by manufacturers of a rotary and push-button type. In this case, it is best to stop at the first option. All this will allow you to more finely tune and not be afraid of a failure in the system.
The modulator is installed in the square wave generator directly on the adapter. In this case, soldering must be done very carefully. First of all, you should thoroughly clean all contacts. If we consider capacitorless adapters, then they have outputs on the upper side. Additionally, there are analog adapters, which are often available with a protective cover. In this situation, it must be removed.
In order for the device to have a 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 (circuit shown below) has a sharp increase in operating temperature. In this case, you should checknegative resistance of the capacitorless adapter.
Overlap Pulse Generator
To make a DIY pulse generator, the adapter is best to use an analog type. Regulators in this case are not required. 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 to 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 a main problem, the pulse generator has an asymmetric oscillation, which occurs due to overloading of the resistors.
Device with symmetrical pulses
To make a simple pulse generator of this type is possible only with the use of inverters. In such a situation, it is best to select an adapter of the analog type. It costs much less on the market than the capacitorless 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 throughput is quite low. As a result, the oscillation excitation parameter will never exceed 4 ms. Plus, the risk of overheating the adapter is added to this.
Given all of the above, it is more appropriate 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 vibration excitation index can reach up to 5 ms. Otherwise, good results cannot be expected. You can check the pulse generator for operability simply by connecting a 20 V power supply. As a result, the negative resistance level 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 the modulator of the PPR2 series is suitable as an option. According to its characteristics, today it is quite reliable.
Generator with trigger
A trigger is a device that is responsible for signal transmission. Today they are sold unidirectional or bidirectional. Only the first option is suitable for the generator. The above element is installed near the adapter. In this case, soldering must be done only after thorough cleaning of all contacts.
Directly adapter can choose even 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 oscillation excitation parameter with a trigger is on average 5 ms. The main problem of the pulse generator is this: increased sensitivity. As a result, these devices are not able to work with a power supply above 20 V.
How to make a high load 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 a high throughput of the system. For this, capacitors are used only capacitive type. They must be capable of handling at least 5 ohms of negative resistance.
Resistors for the device are suitable for a wide variety. If you choose them of a closed type, then it is necessary to provide for them a separate contact. If you still stop at field resistors, then the phase change in this case will take quite a long time. Thyristors are practically useless for such devices.
Quartz stabilized models
The pulse generator circuit of this type provides for the use of only a capacitorless adapter. All this is necessary so that the oscillation excitation index is at least at the level of 4 ms. All this will also reduce thermal losses. Capacitors for the device are selected based on the level of negative resistance. Additionally, the type of power supply must be taken into account. If we consider pulse models, then their output current level is on average 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 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 is increased to 6 ms.
Generators with PP2 capacitors
The generator of high-voltage pulses with capacitors of this type is formed quite simply. Finding elements for such devices on the market is not a problem. However, it is important to choose a quality chip. Many for this purpose acquire multi-channel modifications. However, they are quite expensive in the store compared to regular types.
Transistors for generators are most suitable 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. However, triggers are rarely used. 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 wide margin. To set up the process properly, you must first configure the adapter. If the negative resistance level is at around 5 ohms, then the limiting frequency of the device should be approximately 40 Hz. As a result, the load is removed from the resistors.
Models with PP5 capacitors
High-voltage pulse generator with the indicatedcapacitors are quite common. At the same time, it can be used even with 15 V power supplies. Its throughput depends on the type of adapter. In this case, it is important to decide on 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 level of the limiting frequency. In order to align it, zener diodes are ideal. They are installed, as a rule, near the output port. In turn, resistors are best soldered near the adapter. The oscillatory excitation index depends on the capacitance of the capacitors. Considering 3 pF models, note that the above parameter will never exceed 6 ms.
Main generator problems
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 indicator. If it exceeds 15 V with a 20 V block, then the trigger can significantly improve system performance.
Devices on regulators MKM25
The pulse generator circuit with this regulator includes only closed-type resistors. At the same time, microcircuits can be used even in seriesPPR1. 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 rise even up to 5 ohms.
To solve this problem, you need to use zener diodes. The regulator 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 you can connect an adjustable pulse generator to two contacts.
