To avoid self-excitation, when mounting the UHF scheme may be desirable to ensure a weak link of the grid and anode circuits: distribute relevant parts and wires, shielded wires.
To eliminate the spurious coupling through a common source of supply of the anode in cascades using UHF decoupling filters.
The detector stage is a major step in any receiver. There are receivers that do not have a single gain stage, high or low frequencies. But without taking steps to implement the detection is impossible. The detector should convert high-frequency oscillations in low vibration that modulates the frequency.
For the process of detection is most often used diodes, including semiconductors. In some schemes for the detection is more complex transistor or electron tube.
Consider the operation of the detector stage to the example circuit of the diode detector. Modulated frequency energy fed to the detector stage. Diode has a rectifying properties. Therefore, the current in the diode occurs only during one half period of stress acting on the oscillator circuit.
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