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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 typing up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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Science & Math Theme Crossword Puzzle
April 18, 2021

This Science & Math Crossword Puzzle for April 18th has many words and clues related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical subjects. As always, this crossword contains no names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless it/he/she is related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists amongst us will appreciate the effort. Enjoy!

Reproduction of this puzzle without the express permission of RF Cafe is prohibited.

acr. = acronym, abbr. = abbreviation, pl. = plural, wds. = words

Science & Math Theme Crossword Puzzle for April 18th, 2021 - RF Cafe

1. A system of digital communication whereby information is transmitted in short bursts (2 wds.)
8. Continuous Tone Coded Squelch System (abbr.)
12. Electron beam pattern method used in CRTs (2 wds., pl.)
20. Chemical symbol for silver
21. Opposite of I.D.
22. Sound frequency in the human hearing range (abbr.)
23. Modulation technique that varies the width of pulses in a train (abbr.)
24. Electromagnetic interference (abbr.)
26. Test point (abbr.)
27. A BPF specification (abbr.)
28. Centimeter (abbr.)
30. Computer messaging service (pl.)
33. Intentionally block communications signals
35. Chemical symbol for lawrencium
37. Unit of time (abbr.)
39. Conductor size unit (abbr.)
42. CRT electron beam scan type
45. Chemical symbol for molybdenum
46. Cause a voltage or current waveform to gradually die out
47. Galilean moon
48. Output intercept point (abbr.)
50. Chemical symbol for thulium
51. Cause the temperature to drop
53. Chemical symbol for erbium
54. Chemical symbol for bismuth
56. Schematic label for voltage supply node
57. Device for linearly adding two or more inputs
60. Web's most popular radio frequency engineering site (2 ltrs. + 1 wd.)
63. Printer resolution abbreviation
65. Chemical symbol for platinum
67. Angle having more than 180 degrees but less than 360
68. Chemical symbol for silicon
69. Chemical symbol for silicon
70. Multifunctional silicon devices (abbr.)
71. Front edge of a wing (abbr.)
72. Formed into a specific shape
73. Unix, Linux or Windows (abbr.)
74. Exponent that returns the original number
76. The ringed planet
78. What kind of mathematical quantity has magnitude, but no direction
81. Stock symbol for Advanced Micro Devices
83. Decimeter (abbr.)
84. Chemical symbol for gadolinium
87. Teflon (abbr.)
89. Chemical symbol for einsteinium
90. Global System for Mobile Communications (abbr.)
92. Chemical symbol for xenon
93. Automatic Packet Position Reporting System (abbr.)
96. Intel x86 command for " jump if above"
97. A false signal produced in a superheterodyne receiver’s circuitry (pl.)
101. Specialized mobile radio (abbr.)
102. One component of a complex number (abbr.)
103. Chemical symbol for erbium
104. Decibels above or below a dipole antenna (abbr.)
105. Describes an amplifier capable of tolerating any complex source/load impedance
108. Start frequency (abbr.)
109. Electrical safety organization (abbr.)
111. Abbreviation for minimum voltage
113. "Texting" (abbr.)
116. 1/000 of an inch
118. Unit of apparent power (abbr.)
119. Amateur radio operator who is qualified to administer Amateur Radio licensing examinations (abbr.)
120. Filter type that blocks frequencies in a specified band (abbr.)
121. Layers of a multi-layered PCB
122. Balun with both ports unbalanced (pl.)
123. Popular software language from Borland -- now Embarcadero (2 wds.)
2. A common battery cell size
3. Common gateway interface (abbr.)
4. Electrical overstress (abbr.)
5. Time delay (abbr.)
6. Causes a voltage or current waveform to gradually die out
7. Band between RF and BB
8. Pure carrier (abbr.)
9. Chemical symbol for thulium
10. Chemical symbol for selenium
11. Type of component package (abbr.)
13. PC follower
14. Satellite milieu
15. Microwaves & __ magazine
16. Special diode type that can be switched (abbr.)
17. Automatic Calibration System (abbr.)
18. Nordic Mobile Telephone
19. Type of coaxial transmission line with solid outer shielding
23. Type of data storage IC (abbr.)
25. Stock symbol for Intel
29. Expose to ionizing electromagnetic energy
31. Chemical symbol for molybdenum
32. Chemical symbol for lithium
33. Cable protective covering (pl.)
34. Modulation type (abbr.)
35. Diode circuit to restrain voltage input
36. Semiconductor and calculator company (abbr.)
38. Less than
40. Write-Once (abbr.)
41. "The father of rocketry"
43. Chemical symbol for arsenic
44. BS__ - the degree held by many RF Cafe visitors
46. Type of current
48. Using a logical connection scheme for redundant power supplies
49. Geometric solid having two ends which are similar, equal, and parallel rectilinear figures, and sides which are parallelograms
52. Filter type that blocks upper frequencies (abbr.)
54. Beat frequency oscillator (abbr.)
55. Precision landing system (abbr.)
56. Variable crystal oscillator (abbr.)
58. Country of RF Cafe's residency
59. Resistive component of a capacitor's lumped element model (abbr.)
61. U.S. Spectrum allocation agency
62. Finite Element Analysis (abbr.)
64. Intermodulation distortion (abbr.)
65. Programmable Logic Device (abbr.)
66. Time Division Multiplexing
75. Chemical symbol for neptunium
76. Electro-mechanical control device
77. A compiler directive
79. Wheel attachment point
80. Aircraft tracking system
82. 1E6 nanoseconds
85. Decimeter (abbr.)
86. Electronics manufacturer with "meatball" logo
88. Type of modulation (abbr.)
91. Chemical symbol for scandium
94. Chemical symbol for lead
95. Chemical symbol for holmium
96. JavaScript (abbr.)
98. Colorado Springs military school (abbr.)
99. Global System for Mobile Communications (abbr.)
100. Hub of the solar system
105. Government program to bring electricity to farms (abbr.)
106. Largest broadcaster in the UK (abbr.)
107. Country of RF Cafe's residency
110. Chemical symbol for lanthanum
112. Chemical symbol for manganese
114. Greek letter (micro)
115. Chemical symbol for tin
116. Chemical symbol for manganese
117. Network department (abbr.)
118. Volume unit (abbr.)
119. Abbreviation for peak voltage

See solution below


2021 Crosswords Archive

Visit the Crossword Express website - RF CafeTake a well-deserved break and try your hand at some of these goodies. Every word in the RF Cafe crossword puzzles is specifically related to engineering, mathematics, and science. There are no generic backfill words like many other puzzles give you, so you'll never see a clue asking for the name of a movie star or a mountain on the Russia-China border.

All of these crossword puzzles were created using the fabulous Crossword Express (now called "Magnum Opus") software.

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Science & Math Theme Crossword Solution for April 18th, 2021 - RF Cafe

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