The particular interest of the ADL5519 is focused on bandwidth which is specified up to 8GHz (but still usable in 10GHz with reduced dynamic). With two channels, it is possible to measure the power transmitted to the antenna and the reflected wave, to calculate the return loss and block the PTT when problems arise. As I originally destined it to my EME 13cm station the module is controlled remotely by serial interface (RS232 and RS485) to be installed in the antenna 30m away the shack. A simple RS232 VT100 terminal allows the full control of the assembly as the whole software is embedded. The set also includes some additional features such as measuring the temperature of the PA with KTY probes and power supply voltages.
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The calibration process is the action of putting a well known level at the RF input and entry this level to the microcontroller to correct the measurement error. Of course few points are necessary to obtain good correction and those are frequency dependant. The calibration algorithm finds then the best linear regression minimizing the error over the full dynamic. This process is done by an external test bench based on RF synthesizer and commercial power meter, taking about 50 points Vdetected = f (Pin), and calculating the gain and offset for each frequency. These values are then stored in ROM. The calibration takes into account the linearity error of the detector and the imperfection of input attenuator. The measurement is then displayed directly in dBm. Basically for the kit proposed below two calibration are possible: . Default standard cal (kit#1 and kit#2) accuracy around typ. +/-0.5dB up to 1.2G and typ +/- 1dB for higher freq. . Calibration dedicated to the DetLog board mounted and tested only possible on kit#3. Then the accuracy is around +/- 0.2dB Remark: The calibration algorithm does not work on the frequency axis. It means that between two calibrated frequencies no correction is done. Example: If you want to measure at 3400 MHz you have to use the closer cal, let say 2320 MHz and then correction is not optimal. You could run the built in calibration process at 3400 MHz to calculate the...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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