Towers & Such & Things 2018 (and 2019) forums forums Portland Radio Towers & Such & Things 2018 (and 2019)

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  • #33884

    Might as well get it started now. Go nutz, people.

    Tags: static, what the hell happened, can you hear me now?,construction permits, Grants, programming logic, applications


    The jargon file (version 2.1.2018)

    (Diff: grep post #33885–
    2014 edition: #48
    2015 edition: #5216
    2016 edition: #16587)

    GLOSSARY OF TERMS frequently used in this thread: (in U.S. unless otherwise noted)

    A or Grade A (dBu) = television broadcast field strength contour of 68, 71, and 74 (dBu) for channels 2-6, 7-13 and 14-69 respectively.

    AC = (1) Alternating current, the form in which electric mains power is delivered to customer premises. In alternating current (AC, also ac), the flow of electric charge periodically reverses direction. Alternating current is the type of electrical signal used to drive loudspeakers (2) In radio programming, a format known as Adult Contemporary

    AGC = Automatic Gain Control, a technique in electronic circuits whereby the output is used to adjust the gain of an amplifier.

    AM = (1) amplitude modulation, the oldest form of modulation whereby the amplitude of the transmitted signal is varied in relation to the amplitude of the information being sent (2) the standard broadcast band (530 to 1700 kHz in the U.S.) (3) Ancient Modulation; broadcast band carrying programming targeted mainly at right-wing extremists, bible wavers and other people over 80

    AMSL = the height of a tower or antenna above mean sea level

    amp = (1) amplifier (2) the fundamental measure of electrical current

    ATSC = (1) Suite of proprietary standards developed by the Advanced Television Systems Committee for digital television transmission over terrestrial, cable, and (sometimes) satellite networks, used across North America (mainly US/US territories/Canada [though reluctantly]) and small portions of Asia. (2) Acronym for “Always the Signal’s Crappy” because of its inability to compensate for terrain, distance, weather, physical obstructions, cosmic background radiation and the current astrological cycle, things NTSC and DVB have little trouble dealing with. Frequently ATSC signals arrive at the receiver corrupt and show up a blocky, unintelligible mess.

    ATSC-MH = [ATSC-Mobile/handheld] Variation of the ATSC-T standards used for transmissions to portable, rather than fixed, devices. A kludge meant to sort of accomplish what NTSC-M didn’t have much trouble doing on its own.

    ATSC-QAM = ATSC transmissions modulated using various sizes of quadrature amplitude modulation constellations (64, 128 and 256-level are common) instead of 8-level vestigial sideband modulation. This is done primarily to improve bandwidth usage, thus enabling more program streams to occupy the same 6 MHz channel width than over the air. ATSC-QAM is mostly used on cable TV systems where it is frequently associated with in-the-clear channels and sometimes on closed- circuit (non-broadcast) over-the-air television systems. What most cable TV users mean when they generically say “QAM”.

    ATSC-T = [ATSC-Terrestrial] Terrestrial ATSC-standard 8VSB digital television broadcast transmissions in North America, Mexico and parts of Asia conducted in 6 MHz channels conforming to the standard NTSC-M bandplan. What most people in North America mean when they say “DTV” or “OTA”.

    B or Grade B (dBu) = television broadcast field strength contour of 47, 56, and 64 (dBu) for channels 2-6, 7-13 and 14-69 respectively.

    BUD = a Big Ugly Dish; West Virginia’s state flower.

    C = (1) the speed of light in a vacuum (2) Capacitance (the ability to store charge) (3) microwave radio frequency band between 4 and 8 GHz; commonly used on communication satellites for delivery of television programming by networks to TV stations and cable headends (hope you still have your old BUD!); also occasionally used by wireless computer networking equipment and better-quality cordless home telephones (4) Series of weak, verbose, and flabby programming languages used by card wankers to do boring mindless things under UNIX on dinosaur mainframes. Introduced by Dennis Ritchie in the 1970s as a reminder to be thankful for things like assembly languages. C deliberately takes many (if not most) of the more irritating aspects of COBOL and (dare I say it?) INTERCAL and compresses them into one easy-to-use, hard-to-forget suite. Due to its inclusion in the original UNIX kernel as, in Ritchie’s words, “a sick joke”, and its variants are now used in just about everything with and without a central processing unit today. (Will the insanity ever end?) Hackers believe that C programmers are suits or code millers, and no self-respecting hacker would ever admit to having learned the language. Its very name is seldom uttered without ritual expressions of disgust or horror. Only Brainfuck is slightly less intuitive.

    cart = shorthand for “cartridge”. Usually any of various 2- or 3-track cartridge-loaded endless loop tape systems used in broadcast automation and similar applications; commonly one of several variants of George Eash’s Fidelipac format. Earl Muntz’s consumer-oriented 4-track system of the 1960s (which the more familiar Lear 8-track tape evolved from) is a standard size “A” Fidelipac broadcast cart with a different track configuration and lower tape speed.

    CATV = (1) (generically) cable television. (2) (specifically) informal name for a variant of the standard NTSC-M bandplan used on cable television systems in North America. So-named to differentiate it from the similar, but less common HRC (harmonically-related carrier) and IRC (incrementally-related carrier) frequency plans. Portions of the CATV plan can be received using regular non-cable ready equipment, if the headend carries programming on those channels (particularly 2-13 and 65-139 (UHF broadcast 14-83). The current standard plan ranges from 7 MHz to 1 GHz near-continuously. /North_American_television_frequencies#Cable_television (3) community antenna television; early type of cable TV first deployed in Astoria, OR. CATV, in its most primitive form, literally involves a number of receivers over a wide area (such as a city or an apartment building) connected directly to a central antenna, with possibly an amplifier or distribution hub, receiving terrestrial broadcast signals.

    Class = (1) Deceptive marketing buzzword often thrown around by widescreen TV and monitor companies. Euphamism for “not the actual size of the panel you’re buying”. E.g. a unit marketed as “58-inch class” probably does measure 58 inches in total if you count the 55 1/2 diagonal inches of actual visible display panel plus the 2 1/2 inches of plastic bezel that surround it. (2) In radio and television broadcasting, how much power and coverage a licensee may implement is determined by Zone and Class. Zones (see below) are geographic. Zones determine what classes will be licensed within that zone.

    Classes for FM are:

    Classes for AM are:

    Classes for TV are:

    clear channel = a frequency on the AM band which provides the radio station with the highest protection from interference from other stations. A long story. It no longer means that only one transmitter operates on that channel

    Clear Channel = (note capitalisation) The company that ruined radio. See also “I Heart Radio”.

    contour = a series of points at which the signal of a radio or television broadcast is at a referenced field strength. On flat land a non directional (omnidirectional) antenna will exhibit near circular contours, ideally. Contours are either “protected” contours or “interference contours.” In FM, the actual numerical values of these contours depends on Zone and Class. Also, when you are within 320 km of either Canada or Mexico, different spacing distances and contour values must be observed. Stations in Zone II that are not within 320 km of the Canadian border have their 60 dBu protected contour and three interfering contours, 40 dBu for co-channel, 54 dBu for 1st adjacent and 100 dBu for 2nd adjacent protection.

    CP = (1) construction permit (2) circular polarization

    CPS = Cycles Per Second; see “Hertz”

    CFR = Code of Federal Regulations Title 47: Telecommunications, the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. It is divided into 50 titles that represent broad areas subject to Federal regulation.

    (within title 47 the most discussed parts are normally Part 73 Radio Broadcast Services, but also may refer to Part 0, Part 1, Part 2, Part 15, Part 17, Part 74, Part 95, Part 97)

    CQAM = Compatible Quadrature Amplitude Modulation, a system developed by Motorola for stereophonic broadcasting on mediumwave (AM)

    DA = (1) directional antenna,an antenna which radiates greater power in one or more directions or exhibits greater receive sensitivity in one or more directions (2) distribution amplifier, an amplifier that provides multiple outputs from one input

    DA-N = directional antenna at night

    DA-2 = directional antenna 24 hours, different patterns day and night

    DAB = digital audio broadcasting, the method for audio broadcasting digitally in many countries, principally in Europe.

    dB = decibel, a logarithmic unit used to express the ratio between two values of a physical quantity, often used to express the gain of an amplifier or the loss of signal strength as a signal propagates away from the antenna.

    DBS = Direct Broadcast Satellite (or Service); basically, pay-cable TV over satellite. What the scammy MMDS “wireless cable” thing of the late 80s/early 90s probably could have been. Currently in the US, DBS cable consists/consisted of the major companies Direct TV (AT$T) and DiSH Network (Echostar), leased-bandwidth subsets of the two majors (e.g. Muzak via Echostar) and a handful of niche companies (e.g. Globecast World TV, Sky Angel). DBS services may go out scrambled, in the clear or a mix of the two. Former major pay DBS cable systems in the US included Alphastar, Primestar and USSB.

    DC = (1) direct current, the unidirectional flow of electricity (2) publisher of Batman, Superman and Justice League comic books (3) Seth’s favorite skateboard hightops (second to Vans)

    DOCSIS = /DOK-siss/; /DOK-sees/ Data Over Cable Service Interface Specification, international standards that specify how packet (TCP-IP) data are to be sent over coaxial, hybrid fiber-coaxial and straight fiber cable TV networks. Systems based on DOCSIS are frequently used by cable TV headends to provide two-way Internet connectivity, pay-TV addressing and other telecommunications services like voice telephony.

    DRM = (1) Digital Radio Mondiale (fr./it. Worldwide Digital Radio), European MPEG4-based digital audio broadcasting system used on shortwave and (sometimes) the mediumwave and FM bands that’s sweeping the globe. DRM is an open system like DAB, but not related to and incompatible with DAB. (2) digital restriction management, any of various proprietary and sometimes illegal methods of blocking access to payware (downloaded or on disk) by those who paid, sometimes dearly, to access it. DRM methods vary from simply requiring the user type an “unlock” code on installation, to filesystem tricks, to more unethical and illicit means such as rootkits, and any number of variations and repetitions thereof. DRM has been the source of considerable headaches, confusion and user-inflicted physical damage to computer hardware for millions of computer operators the world over for many years. Somebody who knows what they’re doing can defeat most popular software-based DRM systems in maybe an hour.[citation needed]

    DSSC = double sideband suppressed carrier, a form of modulation used in analog FM (and sometimes AM (e.g. WWV/H)) broadcasting

    DTV = (1) Direct TV, American pay DBS service. (2) digital television; generic blanket term for any of various packet video broadcasting standards. “DTV” is NOT the name of any digital television broadcasting standard!!!

    EMI = (1) electromagnetic interference. (2) defunct major record label and media conglomerate based in England.

    ERP = Effective Radiated Power, in FM radio and television broadcasting, the amount of power you are licensed to transmit, it is equal to transmitter power output (TPO) minus transmission line loss times the antenna gain.

    FM = (1) frequency modulation, the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. (Compare with amplitude modulation, in which the amplitude of the carrier wave varies, while the frequency remains constant.) (2) the FM broadcast band (87.5 to 108.1 MHz throughout most of the world, in either 100 or 200 kHz increments.)

    free to air = A broadcast transmitted without encryption/scrambling and (usually) not requiring a subscription be paid to use it; for example, public-access channels on cable TV or DVB satellites. Compare “in the clear”.

    frequency = the number of occurrences of an electromagnetic field, usually referring to audio or radio signals, per unit time. Also see period and wavelength.

    Gm = transconductance, the ratio of the current change at the output port to the voltage change at the input port, usually in reference to a vacuum tube.

    HAAT = Height above average terrain, used in the prediction of coverage by television stations, FM radio stations and some wireless radio services, HAAT value is determined by taking 50 evenly spaced elevation points (above mean sea level [AMSL]) along at least 8 evenly spaced radials from the transmitter site (starting at 0 degrees [True North]). The 50 evenly spaced points are sampled in the segment between 3 to 16 km (formerly 2 to 10 miles) along each radial. The elevation points along each radial are averaged, then the radial averages are averaged to provide the final HAAT value. Terrain variations within 3 km (2 miles) of the transmitter site usually do not have a great impact on station coverage.

    HAGL = height above ground level

    HD Radio = Suite of proprietary standards for digital audio broadcasting used primarily in North America including Canada and in small portions of Asia and Europe. The HD Radio system was developed by Ibiquity Digital, a cartel of Lucent Technologies (AT$T) and a couple others, but as of 2015 is owned and administered by Digital Theatre Systems (DTS) (you know, movie sound-on-CD; those guys). The currently accepted method is an hybrid mode transmitting redundant data streams in sidebands of an analogue FM (rarely AM) station’s composite audio signal though a full-digital mode does exist. Codec used is HE-AAC. HD Radio promises “near CD-quality” (whatever the hell that means) audio but due to the low bitrate and sample rates tends to fall short of that goal, but can yield very good results under the right conditions. Its real strength is its multicasting capability, providing a service similar to SCA but with relatively higher fidelity. The term “HD” is simply a brand name and not an acronym for anything although it is often (unofficially) defined as “Hybrid Digital”. (See IBAC; IBOC)

    HDTV = high-definition television; generic term for various specific optional high-resolution (often widescreen) image formats given in most current digital TV broadcasting systems (ATSC, DVB, ISDB…) and several obsolete analog systems (CCIR systems A [for its time], E & F; MUSE/Hi-Vision; HDMAC). Mostly due to expense and high bandwidth requirements, high-definition services presently comprise a small minority of terrestrial digital TV broadcasts operating in the US. Do not confuse “HDTV” with any digital television broadcast standard (e.g. ATSC) or digital TV in general. It is not possible for anyone, including the most seasoned of professionals, to use the term in such a manner without making oneself look like a complete and total idiot!!!

    Hz = Hertz, the standard for measuring sinusoidal electricity. Also known as CPS or cycles per second

    I = electrical current, the flow of charge (measured in amperes or amps) (2) singular first-person pronoun used by most people to refer to themselves individually

    IBAC = in-band adjacent channel; what people really mean when they say “IBOC”.

    IBOC = in band on channel, the current method for broadcasting audio digitally on the AM and FM bands in North America

    IF = intermediate frequency,

    IFB = interruptible foldback (or feedback); one-way feed of a TV station’s audio used by the TV station’s producer, director or engineer to communicate instructions (such as cues and camera directions) to remote news gathering personnel in the field. Local IFBs are usually (though not exclusively) found in the 450 and 455 MHz bands, frequently during news broadcasts, and can be monitored on most basic police scanners.

    I Heart Radio = Lipstick on a proverbial pig. A polished turd. “I Fart Radio”.

    IMD = intermodulation distortion

    In the clear = transmitted without any encryption or scrambling; can be received on ordinary unmodified equipment. The main difference between “free-to-air” and “in-the-clear” is whether or not a subscription or permission is required to use the signal in certain applications. For example, Muzak and DMX transmit music via satellite in-the-clear that can be (and often is) listened to by people in their private homes with third-party DVB satellite receivers. It isn’t free-to-air because it still requires a subscription be paid to use it in businesses (such as stores and restaurants). Thus free-to-air transmissions are often (usually) in the clear, but transmissions in the clear may not necessarily be free to air.

    ISDB = Integrated Services Digital Broadcasting, Japanese standards for data broadcasting; used mostly for digital audio and video broadcasting in Japan and South America. ISDB’s high-definition video mode replaced the analogue MUSE standard for high-resolution video transmissions in Japan.

    K = (1) Kilo; SI prefix for thousand (2) Series of three microwave radio frequency bands between 12 and 40 GHz; the Ku-band (12-18 GHz) in particular is commonly used for foreign satellite television broadcasting, backhauls, business music services, commercial direct-broadcast satellite TV services (including pay packages like Echostar and Direct TV, and in-the-clear ethnic and religious TV/audio broadcasting.) The K-bands don’t require as large an antenna as C-band to reliably receive, making them practical for fixed-dish, direct-to-home television broadcasting and computer networking uses.

    Longley-Rice: An alternate method to the FCC method of predicting coverage that addresses the difficulty of determining exactly where a contour line falls when in fact the signal from a given transmitter may rise and fall above and below a given signal level numerous times along the path.

    LPFM = Low Power FM, a class of service in FM broadcasting

    LPTV = Low Power TV, a class of service in TV broadcasting

    NABTS = North American Broadcast Teletext Specification; fork of EIA-608 captioning technology (but standardized as EIA-512) that defines the teletext mode presently used in the US and Canada. A subset of the World Standard Teletext (WST) specification originally adopted in the UK by the BBC and ITV then the rest of the 625/50 world, with modifications to make it 525/60 compatible. Responsible for that black box that takes up the lower half of your TV screen but mostly doesn’t do anything. Some off-air video tapes recorded from ABC and PBS in the late 80s/early 90s will show TV scheduling and other information in this format if you select text service #1 or 2 while the tape is playing. NABTS was used until fairly recently (early 2010s) to enclose ancillary TV show data (URLs and crap) used by Microsnort’s “Web TV for Windows” package (text #3 I.I.R.C.). It still sees occasional use today as a way of sending internal messages to network affiliates and for leased low-speed data services, some of which are known to leak out onto local affiliates during network broadcasts. NABTS also specifies how NAPLPS packets are to be encoded for one-way broadcast over television stations. NABTS is directly related to closed-captioning for the hearing impaired, and transmitted/decoded in a similar way using basically the same hardware.

    NAPLPS = North American Presentation Level Protocol Standard, Telidon’s and AT&T’s (mostly) method of implementing sort of “BBC-like” teletext used on NTSC television systems. Based on the Canadian “Telidon” system. One of three teletext systems implemented in North America alongside NABTS and a slightly modified form of World Standard Teletext (WST) (used by the BBC and just about everybody else). NAPLPS could do some really cool shit (for its time) that the other systems couldn’t, like vector graphics and a primitive form of “interactivity”. Unlike NABTS teletext, and like WST, NAPLPS’ big black window that does nothing takes up almost the entire screen area. NAPLPS was never widely used for broadcast services because AT$T couldn’t get enough TV manufacturers to buy into its very expensive and complex technology, though it did see considerable use on dialup computer services into the mid 1990s.

    NDA = non directional antenna

    NTSC = analog television engineering standards and video transmission system. Acronym for “Never Twice the Same Color”.

    NFG = what happens to all vacuum tubes after a while

    NFM = narrowband FM; frequency-modulated radio signals with bandwidth usually less than 50 kHz (25 kHz deviation). NFM signals between 5 and 25 kHz are commonly used for two-way voice and FSK data communications. Compare WFM.

    P = Electrical Power, measured in watts, the product of current and voltage at the same point.

    PA = (1) power amplifier (2) public address

    PAL = (1) Phase Alternating Line, an analog color video system developed in Germany in the early 1960s, that became common in many countries that use monochrome systems with a 50 Hz refresh rate (and sometimes 60 Hz). Both PAL and NTSC use quadrature amplitude modulated subcarriers carrying the chrominance information added to the luminance video signal to form a composite video baseband signal. The name “Phase Alternating Line” describes the way that the phase of part of the color information on the video signal is reversed with each line, which automatically corrects phase errors in the transmission of the signal by cancelling them out, at the expense of vertical frame colour resolution. This is why European TV sets, unlike NTSC sets, don’t have hue (tint) adjustment controls – it simply isn’t needed. A phenomenon known as “Hanover bars” is sometimes observed in the event of major phasing errors, such as poor reception conditions, in the form of negative-color horizontal striping every other line. (2) Perfection At Last; common reaction to the system’s technical merits after having previously dealt with NTSC and SECAM. (3) Informally, any 576I 50Hz analog video recording or transmission regardless of color encoding, as how “NTSC” is used to informally describe any 480I 60Hz broadcast or recording.

    POL = polarization (also polarisation), in antenna theory the polarization is the orientation of the electric field, and is always 90º from the magnetic field

    Q = (1) in electrical and electronic circuits, bandwidth relative to its center frequency; the Q or quality factor is a dimensionless parameter that describes how under damped an oscillator is. A high Q indicates a lower rate of energy loss (2) the head of R&D in the British Secret Service in the James Bond series (3) Captains Picard/Sisko/Janeway’s immortal nemesis

    QAM = (1) Quadrature amplitude modulation, a form of single-sideband-like modulation used for analogue (i.e. AM stereo) and digital (e.g. cable) information (2) what most cable TV users call it when referring to in-the-clear transmissions (even though the entire system might be QAM)

    RF = radio frequency energy, signals that have a frequency greater than 20,000 Hz (20 kHz). Signals below that frequency are AF or audio frequency signals.

    RF Spectrum Ranges include:

    Very Low Frequency VLF 3 – 30 kHz

    Low Frequency LF 30 – 300 kHz

    Medium Frequency MF 300kHz – 3 MHz

    High Frequency HF 3 – 30 MHz

    Very High Frequency VHF 30 – 300 MHz

    Ultra High Frequency UHF 300 MHz – 3 GHz

    Super High Frequency SHF 3 GHz – 30 GHz

    Extremely High Frequency EHF 30 GHz – 300 GHz

    RFI = radio frequency interference

    RFR = radio frequency radiation,

    S/N = Signal to noise ratio of either the RF, visual or audio signal with reference to the associated noise floor.

    SCA = Subsidiary Communications Authorisation; method of transmitting narrowband (<= 8 kHz, usually) analogue FM audio programming alongside wideband FM radio transmissions in the upper portion of an FM broadcast band channel. SCA transmissions are/were frequently (though not always) used for pay-subscription programming such as Muzak and radio reading services. SCAs go out at maximum 10% modulation relative the main wideband carrier and are prone to multipath distortion, crosstalk, fading and similar effects. SCA audio almost always goes out in the clear. This method is becoming increasingly obsolete s newer methods capable of delivering higher-fidelity audio and tighter access controls, such as ATSC or Ibiquity channels and Internet streaming, continue to replace them. The late author and publisher of the DX guide “FM Atlas”, Bruce F. Elving PhD., was a proponent of using SCA to transmit supplemental material to the station’s main broadcast. SCA was officially deregulated by the FCC in the 80s, to Muzak’s chagrin, and became the method of choice for libraries and blindness advocacy groups to send out recorded readings of books and magazines. Similar technology was used by NTSC television stations to send alternative audio programming.

    SECAM = Séquentiel couleur à mémoire (Sequential Colour And Memory), an analog color video system developed in France. SECAM transmits each color line sequentially and stores each in delay lines until they can be writen to the screen raster. The other systems use the phase difference between two subcarrier components relative the baseband monochrome picture to obtain full color. Also “System Entirely Contrary to the American Method” since chronologically it follows NTSC, predates PAL and is mechanically a total departure of either.

    SOL = the prevailing attitude of employees when they learn Clear Channel has automated their station (see above)

    SSB = single side band, a form of amplitude modulation

    STL = studio-transmitter link, a system to deliver the program audio chain to the transmitter site from the studio

    T = Period, the inverse of frequency or the time for the electric wave to go through one full cycle.

    TPO = transmitter power output

    THD = total harmonic distortion

    THX = how’d that get in here?

    translator = a low power class of service in FM broadcasting intended to repeat programming from an originating full power class station

    V = voltage, the electrical potential (difference) between two points

    VSB = vestigial sideband, a form of modulation (see NTSC)

    wavelength = in a sinusoidal wave, the distance over which the wave’s shape repeats





    WE = (1) Western Electric, defunct American producers of the greatest telephones ever made (2) first-person collective pronoun that individual ham radio operators refer to themselves as because personal individuality is not a recognised concept in the ham radio religion (contrast “I”)

    WFM = wideband FM; frequency-modulated radio signals with bandwidth usually greater than 50 kHz (25 kHz deviation). WFM signals of around 200 kHz bandwidth are found between 88 and 108 MHz where they are used for composite one-way audio/data transmissions. Some types of relatively narrowband FM signals between about 25 and 50 kHz bandwidth (such as those used sometimes by ham radio operators and formerly by AMPS cellular telephone service) are confusingly referred to as “wideband” because they are wider than others of similar nature.

    XTAL = Crystal

    XMTR = Transmitter

    XFORMER = Transformer

    Z = impedance = the measure of the opposition that a circuit presents to a current when a voltage is applied (DC resistance plus AC resistance)

    Zones = In FM and TV broadcasting, for the purpose of allotments and assignments, the United States is divided into three zones

    \lambda = wavelength

    \omega = Resistance in Ohms

    \pi = pi, the ratio of a circle’s circumference to its diameter, and is approximately equal to 3.14159

    Ø = (1) the null set, (2) undefined (3) diameter (4) the sum and total of your enemy’s knowledge . . . depending on which side of this board it appears.

    60 dBu = 1 mv/M In FM broadcasting, the distance from the antenna where the propagated signal has attenuated to this value is considered in FM broadcasting as the limits of your Primary coverage or Protected contour. dBu references dB above 1 microvolt per meter (uV), that is to say 60dBu is 1,000 times the voltage at 0dBu ( 1 microvolt). In Zone I and I-A, Class B1’s primary protected contour is 57 dBu and for Class B’s it is 54 dBu. For all other stations in FM broadcasting, 60 dBu is the primary protected contour.

    Deliberately plagiarized and ripped off from Andy Brown’s post from a few years ago with various additions made and liberties taken by me. (Live with it. Laugh a little.)


    The opinions and views expressed in this post may not necessarily represent those of nosignalallnoise or anybody else in particular. Or maybe they might. Who knows. Who’s keeping track? Who cares?

    Andy Brown

    Safe Harbor

    The safe harbor refers to the time period between 10 p.m. and 6 a.m., local time. During this time period, a station may air indecent and/or profane material. In contrast, there is no safe harbor for the broadcast of obscene material. Obscene material is entitled to no First Amendment protection, and may not be broadcast at any time.

    For a full explanation of indecency, profanity and obscenity (they are all different as pertaining to broadcasting) visit


    skin effect

    The tendency for alternating current (AC) to flow mostly near the outer surface of an electrical conductor, such as metal wire.The effect becomes more and more apparent as the frequency increases.


    STA Special Temporary Authority

    When a broadcast station cannot operate in accordance with its license due to equipment failure, damage to licensed transmission systems, or other causes, the station may request an STA. Section 73.1635 of the rules governs STA operation; other related rule parts are 73.1680 (emergency antennas); 73.1560 (reduced power); 73.62 (AM directional antennas) 73.1740 (reduced hours).


    SWR or VSWR

    Standing Wave Ratio or Voltage Standing Wave Ratio

    In radio engineering and telecommunications, standing wave ratio (SWR) is a measure of impedance matching of loads to the characteristic impedance of a transmission line or waveguide.

    In lay terms, the SWR indicates the amount of reflected power as measured at a specific point in the system. No reflected power is an SWR of 1.0 although in most non laboratory situations that is impossible to achieve. An SWR of 1.2 is considered very good. An SWR of 1.0x is considered excellent.

    The SWR is usually thought of in terms of the maximum and minimum AC voltages along the transmission line, thus called the voltage standing wave ratio or VSWR (sometimes pronounced “vizwar”). For example, the VSWR value 1.2:1 denotes an AC voltage due to standing waves along the transmission line reaching a peak value 1.2 times that of the minimum AC voltage along that line. The SWR can as well be defined as the ratio of the maximum amplitude to minimum amplitude of the transmission line’s currents, electric field strength, or the magnetic field strength. Neglecting transmission line loss, these ratios are identical.


    Phasor (phasor cabinet) In AM directional antennae systems (multiple towers) the transmitter output is connected to the phasor where there is a separate output for each tower. The purpose of the phasor is to adjust phase and magnitude of the radio frequency current being sent to each tower in the directional array. The differences in these parameters are what creates the directional pattern.

    (take a cookie baking sheet pan, fill with water, drop a stack of 4 pennies in one place near the center of the tray and then 4 quarters in another place near the center. Observe the interference patterns. This is a very basic way to explain how directional patterns are created using multiple towers).

    The above applies to AM broadcasting only. FM directional antenna are done differently.



    Question, What is critical Hours? Can they air 2 hours before and after sunrise/sunset local time? Is that means KOOR 1010 can start (1/2/2018) approx. 5:50am and end approx. 6:38pm?


    Critical Hours is the first two hours after local sunrise and the last two before local sunset. It only applies to clear channels to protect the primary or primaries on those channels. The amount of power etc. authorized is listed on the license. I almost hate to mention this but “things” is different from “such”. “Such” suggests something similar whereas “things” does not. Could we please change it back to “such”? This is the only legacy I have here and I don’t ask for much, just “such”. 🙂


    Thanks for the additional terms, I’ll add it to the file!



    Hopefully, 2018 will reveal the answers to a number of mysteries:

    – To what location will 1150 move its transmitter?
    – Will Westside LPFMs 96.7, 98.3, and 101.5 be on the air?


    washnotore said elsewhere:

    Something to look forward to in 2018. Phoenix to serve as the “model market” for ATSC 3.0. Ten stations in the market will deploy the next-generation TV standard before early April. Here localy we have Watch TV working on ATSC 3.0 roll out.

    Meanwhile LG is coming out with new receivers that have both ATSC 1.0 AND 3.0 decoders. They are supposed to be available soon albeit in first generation. Unless there is some type of firmware/software upgrade option that is built into these new smart sets, you may want to wait until the dust settles.

    It has been a while since Watch TV was testing their ATSC 3.0 signals on channel 20.

    Post #33995


    “To what location will 1150 move its transmitter?” If they don’t/can’t move it to the 1520 site, I think it’s finished. Anything else would be cost prohibitive or too far away. 1150 is awfully close to 1190 and the 1520 site must be less than a mile from KEX, so it will take some manipulation if it’s even possible.


    KTFH (FM) 88.7 FM LEES CAMP, OREGON FID# 176409
    KTFH is a Class A 100 watt non-commercial educational radio station operated by Cascade (“CCR”) in the small community (population ~200 persons) of Lees Camp, Oregon. Due to chronic technical problems, economic unsustainability (sic), and inviable listership, licensee wishes to propose change of comminity of license. Instead of handing its license back to the FCC, CCR has looked for alternatives to retain the facility for local non-commercial community radio usage. In searching for the nearest community that it could possibly relocate to with an open NCE channel, the only option appears to be Gearhart, Oregon.

    Andy Brown

    Salem Media’s proposal to move their Eaglemount WA translator to Portland as a “fill in” for KDZR AM on 105.5 and sandwich it in-between KXRU, K288FT and KSXM has met the same fate as their initial attempt to put it on 107.9 from Mt. Scott. The FCC has denied Salem Media’s Petition For Reconsideration, dismissed their second amendment to move to 105.5, and granted KXRU’s informal objection. Salem Media’s application is now expired. They have to start over from scratch. Congratulations to Ed at KXRU for following through on this at my urging for without the informal objection, this would have been rubber stamped ‘granted’ by the FCC.

    Salem Media and the rest of the corporate sloths need to realize that they aren’t going to slip one of these bastardized translator moves past the FCC without a fight.

    Score one for the little guys.


    Meanwhile, EMF objects to the sale of KTFH Lees Camp. Says they’ve been off the air for over a year.
    Today, the FCC just changed the status to DKFTH

    OR BALED-20171204AAJ
    KTFH 176409 CASCADE COMMUNITY RADIO Voluntary Assignment of License E 88.7 MHZ LEES CAMP, OR
    Petition to Deny filed 01/03/2018


    KZRI can now apply/upgrade for more power now.
    Why could not 1150 diplex wth KBPS?


    KZRI is currently 0.1 miles from overlapping co-channel KBVR Corvallis. So unless they do a directional antenna there’s no upgrade for them!


    I wonder whether legal issues could arise from KBPS accepting payments from a for-profit entity (in this case Bustos). I am not a lawyer, so I would appreciate if somebody could enlighten me on this matter.

    From a technical standpoint, there is one “gotcha.” The KBPS tower is shunt-fed through a sloping wire. The FCC doesn’t license sloping wire feeds anymore; modern shunt-fed towers are fed through a symmetrical set of wires that surrounds the tower. KBPS is grandfathered to use this antenna, but KGDD would not be.

    Fun fact–KOAC is another grandfathered station that uses sloping wire feeds on its towers.

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