Extra exam question E7C10
Subelement E7, PRACTICAL CIRCUITS· Group E7C
Which of the following filters is used in a 2-meter band repeater duplexer?
- A.A crystal filter
- B.A cavity filter (correct answer)
- C.A DSP filter
- D.An L-C filter
WhyA cavity filter is used in a 2-meter band repeater duplexer. Cavity filters, resonant metal cavities tuned to pass or reject specific frequencies, are used in a 2-meter repeater duplexer to let a single antenna transmit and receive simultaneously on closely spaced frequencies without the transmitter overwhelming the receiver, answer B. Crystal filters, DSP filters, and ordinary LC filters don't have the combination of high power handling and steep, precisely tuned rejection that a duplexer's cavity filters provide.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
Related questions
- E7C01How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network’s input and output?
- E7C02What is the frequency response of a T-network with series capacitors and a shunt inductor?
- E7C03What is the purpose of adding an inductor to a Pi-network to create a Pi-L-network?
- E7C04How does an impedance-matching circuit transform a complex impedance to a resistive impedance?
- E7C05Which filter type has ripple in the passband and a sharp cutoff?