Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters PCB Directory Rigol San Francisco Circuits Reactel RF Connector Technology TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines RF Cafe Software RF Cafe Sponsor Links Werbel Microwave Thank you for visiting RF Cafe!
everythingRF RF & Microwave Parts Database (h1) - RF Cafe

Frequency Synthesizers: Concept to Product
Answers to RF Cafe Quiz #35

RF Engineering Quizzes - RF CafeAll RF Cafe Quizzes make great fodder for employment interviews for technicians or engineers - particularly those who are fresh out of school or are relatively new to the work world. Come to think of it, they would make equally excellent study material for the same persons who are going to be interviewed for a job. Bonne chance, Viel Glück, がんばろう, buena suerte, удачи, in bocca al lupo, 행운을 빕니다, ádh mór, בהצלחה, lykke til, 祝你好運. Well, you know what I mean: Good luck!

Click here for the complete list of RF Cafe Quizzes.

Note: Some material based on books have quoted passages.

Return to RF Cafe Quiz #35

RF Cafe FEatured Book - Frequency Synthesizers: From Concept to ProductThis quiz is based on the information presented in Frequency Synthesizers: From Concept to Product, by Alexander Chenakin (Phase Matrix). Artech House is the publisher. Note: Some of these books are available as prizes in the monthly RF Cafe Giveaway.

1.  What would the spectrum analyzer display for an ideal sinewave output look like?

d)  A single vertical line at the center frequency that has no width.

     See page 3.

2.  For a fundamental frequency of 100 MHz, what is the first harmonic frequency?

b)  100 MHz

     By definition, the first harmonic is the fundamental (1f), the second harmonic is 2f, the third

     is 3f, etc. The first overtone frequency is the same as the second harmonic (2f). See page 5.

3.  Increasing the oscillator signal-to-thermal noise ratio has what effect on the noise curve?

b)  The entire curve shifts down.

      Maintaining a higher power level in front of the resonator and/or reducing the active device

      noise factor while setting the active device gain to its optimum value will increase the oscillator

      signal-to-thermal noise ratio. See page 44.

4.  When is harmonic mixing typically used?

a)  When the LO signal needs to be multiplied.

      A lower fundamental frequency oscillator can be used for cost and simplicity reasons, and then

      a harmonic of the fundamental is used for mixing. For example the 3LO x 1 RF product might be

      the preferred mixer output rather than the more common 1LO x 1RF product. See page 71.

5.  What distinguishes a lumped element from a distributed element?

b)  The physical length of the component compared to signal wavelength.

      A loose rule-of-thumb is that if an element is greater in length than 1/10 of a wavelength of

      the highest frequency, analyze it as a distributed element. See page 96.

6.  Which circuit is most likely to be found in a

      feed-through EMI filter?


      An EMI filter is designed to block high frequency signals will passing DC bias and relatively low

      frequency control signals. That dictates a lowpass filter topology. The series inductor chokes off

      high frequencies while the parallel capacitor shunts high frequencies to ground. See page 106.

7.  Why might resistors be added in series to

      control ports on a synthesizer's control port?

a)  Current limiting to protect the input circuitry

     against a short or overvoltage.

     See Figure 4.13, on page 121.

8.  What PCB layout strategy is required for synthesizer design?

c)  Each component must be located and oriented based on how other components are placed.

     Many components are sensitive to cross-coupling with other components and much be situated

     to minimize the interference. For example, inductors should not me placed parallel to each other

     when in close proximity in order to avoid effectively creating a transformer. See page 133.

9.  What is the phase noise degradation of a 1 GHz synthesizer that uses a 10 MHz reference


c)  40 dB

     Phase noise is degraded according to the equation 20 * log (fc/fRef).

     So 20 * log (1000/10) = 40 dB. See page 149.

10.  What advantage does a Fractional-N synthesizer have over Integer-N?

d)  Fractional-N permits output frequency steps that are small that the input reference source.

     See page 151.

Innovative Power Products Passive RF Products - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
ConductRF Phased Matched RF Cables - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free


About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website: