The COM USB adapter is a device that allows a personal computer to connect to various peripheral equipment. Unfortunately, modern models of system units sometimes do not have very important outputs. Thus, the user is limited in their capabilities.
If we consider a device such as a receiver, then it cannot be connected to the cable. In this case, only the adapter (adapter) can help the user . According to the type of connectors, these devices differ. In addition, it should be noted that making them at home is quite real. However, first of all, it is important to familiarize yourself with their device.
Simple adapter circuit
The USB-COM adapter circuit includes a port, a modulator, a converter, and a resistor. In some cases, an amplifier may also be located on the board. Moreover, most often wired models are selected. Resistors in this case are used only open type. This is necessary in order to increase the maximum frequency of the device. Thus, the response time of the signal will be in the region of 20 ms. Among other things, the bandwidth of the device should be considered. To increase this parameter, many experts modulators advise using only two-way.
Type A standard models
Making a Type A USB-COM adapter with your own hands at home is quite simple. The chip in this case is more appropriate to select the type PP21. Only the converter will help stabilize the process in the device. For the normal operation of the model, you will also need a high-quality modulator. For the indicated microcircuit, it is necessary to select only the low-frequency type. All this will allow the signal response parameter to be kept at 30 ms.
For better current conductivity, experts also recommend the use of low power transistors. In this case, they must withstand the maximum voltage at 3V. In general, these adapters are excellent for various kinds of receivers. In addition to them, you can connect radios with connectors of type SR101.
Type A Mini Models
Adapters of this type are capable of supporting many formats. It is impossible to add them without converters. In addition, you need to choose a chip series PP22. There should be three transistors on it. In this case, two of them must be placed near the converter. In this case, the modulator is important to select the pulse type. The average signal response rate is about 30 ms. For stable operation of the peripheral device, this is quite enough.
The cable in this case must be attached to the back of the chip. It is important not to touch the modulator during the soldering process. Transistors also need to be kept clean. The conjugation of the circuits is provided by the frequency amplification cascade. On average, this parameter fluctuates around 12 Hz. To increase the current conductivity, some experts recommend the use of amplifiers. The port for the device is connected last. The driver for the USB-COM adapter is selected separately.
Type A Micro Models
Making Type A a micro USB-COM adapter with your own hands is quite difficult. This is largely due to the presence of a non-standard port. Throughput for it should be provided rather high. In this case, the signal response parameter must be at least 20 ms. Separately, you should also pay attention to the search for the converter.
To increase the clock frequency in the device, many of them select a symmetrical type. At the same time, transistors are selected in an open modification store. On average, they withstand voltage at the level of 3A. Alternatively, consider combined subspecies. All this will ultimately increase the response speed of the signal.
How to make a type B adapter to standard?
The presented USB-COM adapter cable is assembled for devices for which the connector is of the RSR21 type. First of all, in the store you need to choose a modulator. In this situation, you can stop at a stepwise analogue. However, its bandwidth is quite low. Also in the future, certain problems with overlapping circuits may occur. To solve the presented problem, you can use oscillatory modulators.
They are quite expensive in the market, but testing of devices shows that they are very good. First of all, they are distinguished by the presence of copper contacts. Thus, their current conductivity is high. Among other things, it works pretty well with a chip like PP20. The port in this case must be installed last. In this case, the cable for it is selected separately.
Type B mini adapters
This COM USB adapter is being assembled using a chip like PP220. In this case, the converter must be selected with a chromatic resistor. Additionally, it is important to use only a high frequency modulator. To increase the response speed of the signal, many experts recommend the use of open transistors.
However , the bandwidth of the device will be significantly reduced. As a result, a problem may occur with the installation of the device driver. Additionally, a trigger is mounted on the USB-COM adapter. This element in the system is responsible for pairing loops. This process occurs in a grid triode. The frequency gain in this case increases significantly. The port for the adapter is selected without a selector.
Micro Type B Model
Adapters of the presented type are assembled quite simply. First of all, it should be noted that today they are quite in demand. They are suitable for all devices on which there is an RSR 23 connector. Converters are selected on a microcircuit only of a pulse type. In this case, transistors are best used standard. However, many experts still give their preference to open-type analogues.
The bandwidth parameter in this case will depend on the type of amplifier. If you use the low-frequency modification, then problems with the device are inevitable. In turn, longitudinal modifications significantly increase the current permeability parameter. The cable in this case is soldered to the convection output of the chip.
How to choose a model in the store?
For devices with an RSR21 type connector, select the high-frequency adapter. It must withstand a minimum load of 3 A. Copper in conductors must be oxygen-free. In this case, you can count on a good bandwidth of the device. Digital formats adapter must support "Dolby" and "Tru".
In turn, the video system should work with 720p. Amplifiers in devices are usually mounted non-contact. However, some models have cheaper analogue modifications. The outer shell of the model must be made of polyvinyl chloride. The signal response rate parameter is on average around 30 ms. A quality adapter will cost about 2500 rubles.
USB mini 4P specifications
The specified USB-COM adapter (adapter) differs from other devices in that the modulator in it has a two-sided type. Due to this, his bandwidth is pretty good. For audio devices, this model is ideal. Traverse in this case is set intermediate. To stabilize the signal in the device, a high-frequency amplifier is used. The parameter response rate of the model signal is at 25 ms. On average, the frequency indicator of the device is located at around 23 Hz. To adjust the current, the adapter has a small reflector.
USB Model 1394B
Adapters of this type are capable of boasting a rather high response speed of the signal. The converter in this case has a low frequency. In turn, the modulator is installed with a limit frequency of 23 Hz. All this allows you to quickly stabilize the input voltage. Support for major formats is provided by installing the device driver. The amplifier in this case is a pulse type. In turn, high throughput was made possible by increasing the generation parameter.
The disadvantages of this adapter include a low overlap range. In this regard, conflicts often arise with the system when connecting peripheral devices. In addition, it should be borne in mind that the chip in the model is installed in the PP19 series. Due to this, the intermediate frequency parameter never exceeds 30 Hz.
USB TDK device
This USB-COM adapter is most suitable for connecting receivers with a RSR30 type connector to a personal computer. The converter in this case uses high sensitivity. In this case, the microcircuit is installed meridional. The modulator is connected to it with an operating frequency of 28 Hz. High bandwidth in the device is provided by high-quality transistors.
It should also be noted that the deviation of the transducer is quite rare. However, there are still drawbacks to this adapter. First of all, they are associated with wave distortion. As a result, device synchronization can take a lot of time from the user.
USB-COM RS232
The USB-COM RS232 adapter is used to connect devices with RSR21 connectors. In this case, the high quality of the modulator deserves special attention. In this case, the chip is used in a device of type PP21. The transistors of this model are installed analog type. They do not differ in special bandwidth. However, the parameter of the signal response speed for the presented adapter is at the level of 30 ms. This was largely achieved through the installation of a powerful converter.
He is able to maintain the working frequency in the system at 23 Hz. Contacts in this case are copper. All major formats are supported by the system. A driver for the USB-COM adapter can be purchased from the manufacturer. The outer shell of the device is made entirely of polyvinyl chloride. Additionally, it should be noted that the limit frequency parameter is exactly 30 Hz. In this regard, the bandwidth of the device is quite high.
USB Modification MINI8M
This COM (port USB) adapter is suitable for devices that have an RSR26 series connector. In particular, these models are actively used to connect receivers to personal computers. Additionally, the modification can be installed on laptops. In terms of dimensions, it is very compact. The outputs on the chip are provided by the manufacturer for coaxial type. In sensitivity, this model does not differ from other devices. In addition, it should be noted that the operating frequency parameter is at 21 Hz damage.
In this case, the conductivity of the resistors is not very high. As a result, the signal response rate is on average 20 ms. The intermediate frequency model is 33 Hz. Modulators in this adapter are thermo-optical. Wave distortion in them occurs quite rarely. Additionally, it should be noted that the presented adapters often suffer from elevated temperature. You can use them at a maximum of 40 degrees.
USB parameters MINI8P
This COM ( USB port ) adapter is most often installed under various receivers. The operating frequency is exactly 25 Hz. In this case, the signal response rate is at the level of 40 ms. The converter in this case is used by the manufacturer of the non-chromatic type. Its throughput is rather weak. However, it can withstand a load of about 3 A. Due to this, stability is ensured at a good level, and transistors in the device rarely burn out. Of the shortcomings, a sharp increase in the clock frequency should be noted. This happens due to the desynchronization of the modulator.
Devices with a connector on the controller
USB-COM adapter with a connector on the controller is today considered quite popular. Chips for it can be selected a variety. As a rule, converters are installed low-frequency. This is due to the fact that the response speed of the signal is good for the models. Modulators for adapters of this type are used only meridional. All this leads to an increase in the limiting frequency to 30 Hz. However, the stability of the device can be controlled by installing an amplifier on the model.
Peripheral Connector Models
Adapters with a connector on the peripheral device are not very popular. First of all, they are absolutely not suitable for laptops. Additionally, they can only use the PP13 series chips. All this ultimately entails a number of problems. First of all, it should be noted that the intermediate frequency parameter is low at the level of 10 Hz. This is due to the lack of an input resistor on the board.
Also, problems with such models often arise due to a sharp drop in voltage. This happens when the load on the converter exceeds 3 A. However, despite all the above disadvantages, adapters with a connector on the peripheral device are still useful when it comes to connecting equipment with RSR24 output.