These custom-made engineering and science-themed crossword puzzles are done weekly for the brain-exercising benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or not this type of mental challenge helps keep your gray matter from atrophying in old age, but it certainly helps maintain your vocabulary and cognitive skills at all ages. A database of thousands of words has been built up over the years and contains only clues and terms associated with engineering, science, physical, astronomy, mathematics, chemistry, etc. You will never find a word taxing your knowledge of a numbnut soap opera star or the name of some obscure village in the Andes mountains. You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which, if you don't already know, might surprise you. cruciverbalist: [noun] cruci- ("cross") + verbal ("words") + -ist ("agent, person") -- A person who constructs or works crosswords.
Reproduction of this puzzle without the express permission of RF Cafe is prohibited.
acr. = acronym, abbr. = abbreviation, pl. = plural, wds. = words 
<click for full size to print> 1. Equation
5. 2 Down + _______ + 13 Down + 15 Down spreadsheet, which performs 10 Down*
9. Greek letter
11. Switch position
12. Conductor size unit (abbr.)
14. Relative power level unit (abbr.)
17. Unit of inductance (abbr.)
18. Beat frequency oscillator (abbr.)
19. Hydrogen, argon, neon, xenon, etc.
20. Ovenized crystal oscillator (abbr.)
22. System for underwater navigation (pl.)
25. Masses
27. Chemical symbol for scandium
28. Unit of frequency (archaic, abbr.)
29. Key feature in a high level overvoltage protection device
30. Chemical symbol for berkelium
31. Chemical symbol for thallium
32. Unit of frequency (archaic, abbr.)
34. Chemical symbol for ruthenium
36. Multifunctional silicon devices (abbr.)
38. Radio signals from the cosmos (abbr.)
40. Chemical symbol for silicon
41. European equivalent to the U.L.
42. Software object reference name
43. Software engineering tool (abbr.)
44. Type of chart use for project planning
45. Electrical safety organization (abbr.)
48. Chemical symbol for radon
50. Unit of apparent power (abbr.)
51. Type of flip-flop
52. Chemical symbol for chlorine
54. Unix, Linux or Windows (abbr.)
55. Semiconductor and calculator company (abbr.)
57. Unit of length (abbr.)
58. 30 Hz to 300 Hz
59. Opposite of I.D.
61. Opposite of O.D.
62. Satellite EHF Communications for Mobile Multimedia
64. Large loudspeaker designed primarily to reproduce low frequency audio signals
67. Electronics Industry Association (abbr.)
68. Plane circular area (pl.)
69. Maximum Usable Frequency
70. Internet protocol (abbr.)
71. Cellphone band directly above DCS
73. Semiconductor device type (abbr.)
74. Unit of length (abbr.)
76. Designation for a DoD-defined component or system (hyp.)
80. Grouping of wires or cables
81. Code used for automating software tasks | 1. What current is said to do (pl.)
2. __ + 5 Across + 13 Down + 15 Down spreadsheet, which performs 10 Down*
3. Numerical basis for decibels (abbr.)
4. Modulation type (abbr.)
5. Chemical symbol for cobalt
6. Type of logic gate
7. A common battery cell size
8. Reflected radar or sonar signal (pl.)
10. Mathematical calculation of RF component string (2 wds.)
12. Colorado Springs military school (abbr.)
13. 2 Down + 5 Across + ____ + 15 Down spreadsheet, which performs 10 Down*
15. 2 Down + 5 Across + 13 Down + ____ spreadsheet, which performs 10 Down*
16. Imaging device (abbr.)
18. Low- to mid- frequency RF connector
21. Transmit Incremental Tuning (abbr.)
23. Generate a periodic signal
24. Special diode type that can be switched (abbr.)
25. Largest broadcaster in the UK (abbr.)
26. Electrical terminal, normally left unconnected at one end
32. 1E6 nanoseconds
33. Constellation : The scales
35. Unit of time (abbr.)
36. Band between RF and BB
37. Opposite of a source (pl.)
39. Test equipment (abbr.)
45. PCB mask exposing ray (abbr.)
46. JavaScript (abbr.)
47. Amateur radio abbreviation for the Oceania region (abbr.)
49. Unit of time (abbr.)
51. Common average used for sinewaves (abbr.)
53. The "L" in VLF
56. Current-voltage phase mnemonic
57. Million multiply accumulate operations (abbr.)
60. Weatherproof cover for a radar antenna
61. Type of secondary radar system (abbr.)
62. Type of chart used to plot immittance
63. Output intercept point (abbr.)
65. One port of an amplifier
66. Increases voltage linearly
72. "Texting" (abbr.)
73. U.S. Spectrum allocation agency
75. Chemical symbol for strontium
77. Network department (abbr.)
78. Chemical symbol for einsteinium
79. One type of electron spin |
See solution below
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