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Introduction to Scanning

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                  Introduction to Scanning
                    by Bob Parnass, AJ9S

  [NOTES: This article may not be reproduced in whole or in
 part on CDROMS, in bulletin boards, networks, or
 publications which charge for service without permission of
 the author.  It is posted twice monthly on the USENET
 groups,, and  It is also available electronically from
 the ftp archive on the official USENET
 FAQ library

 The author writes a monthly "Scanner Equipment" column for
 Monitoring Times magazine, published by Grove Enterprises, but views expressed in this
 article are his own.

 This introduction is intended for people new to the
 scanning hobby and is oriented to scanning in the USA.
 High level overviews of the following topics are presented:

    Why Scanning?
    Is Scanning Legal?
    What Scanner Should I Buy?
    What is a CTCSS and DCS Tone Squelch Feature?
    How Do I Determine the Proper CTCSS or DCS Code?
    Scanner Antennas
    Coaxial Cable Feedlines
    Where Can I Buy A Scanner?
    Modifying Your Scanner
    Scanner Repair Shops
    Where Can I Obtain Frequency Information?
    Do Your Own Frequency Detective Work
    How Can I Use Equipment to Uncover New Frequencies?
    Scanner Clubs and Mailing Lists

                        Why Scanning?

 Every day and night, scanner hobbyists are entertained by
 what they overhear on their radios.  Police cars, fire
 engines, ambulances, airplanes, armored cars, trains,
 taxis, and buses are all equipped with radios and you can
 listen to them.  You can monitor the local sheriff and fire
 departments to hear about events "as they happen," before
 the news reporters hear about them.  Hostage dramas, bank
 robberies, car crashes, chemical spills, neighbor and
 domestic disputes, tornado sightings are all fair game.  In
 a single afternoon, you can hear a high speed police chase,
 Drug Enforcement agents on a sting operation, and
 undercover FBI agents as they stakeout a suspect.

 How about listening to a team of G-men protect the
 president while transmitting in the 167 MHz range?

 Baby monitor intercoms are actually transmitters and you
 can hear them between 49.67 and 49.99 MHz.

 Stay ahead of road conditions by listening to highway road
 crews, snow plows, and traffic helicopter pilots.  Many
 midwesterners monitor the state police and and county
 sheriff to learn of approaching tornados long before
 warnings are broadcast on TV and commercial radio.  Take
 your scanner to sporting events and listen to race car
 drivers, football coaches, etc., in the 151, 154, and 468
 MHz ranges.

 Monitor the everyday hustle and bustle of businesses, from
 cable TV repair crews tracking down pirate descrambler
 boxes, to security guards at your nuclear power plant or
 mall security guards chasing a shoplifter.

                     Is Scanning Legal?

 In the United States, scanning from your home or at work is
 perfectly legal in most situations.  The Electronic
 Communications Privacy Act of 1986 made it illegal to
 listen to mobile phones, common carrier paging, and a few
 other types of communication.  Public law 103-414, signed
 Oct. 25, 1994, amended the law (Title 18 USC, Part I,
 chapter 119, sections 25110 and 2511) and outlaws listening
 to cordless phones, too, but many scanners cover these

 It is illegal for companies to sell or import into the USA
 recently manufactured scanners which cover or can be easily
 modified to cover the cellular phone frequencies, but sales
 by private individuals will still be allowed.

 The rules define "readily altered by the user" as "clipping
 the leads of, or installing, a simple component such as a
 diode, resistor and/or jumper wire; replacing a plug-in
 semiconductor chip; or programming a semiconductor chip
 using special access codes or an external device, such as a
 personal computer."

 Speaking of privacy, federal law also requires you to keep
 what you hear to yourself and not use the information you
 hear on your scanner for personal gain.

 Be aware that several states have laws pertaining to
 scanning while in your car.  Indiana restricts some
 portable scanners.  A few states have enacted their own
 laws against listening to cordless phones.  You can find
 out about these restrictions in a paperback book, Listeners
 Lawbook, compiled by Frank Terranella, Esq.  available for
 $9.95 + shipping from Grove Enterprises, 7540 Highway 64
 West, Brasstown, NC 28902.

                 What Scanner Should I Buy?

 Radio Shack and Uniden (maker of Bearcat, Regency, and
 Cobra brands) offer a wide choice of scanners.  Radio Shack
 scanners are actually manufactured by both GRE (General
 Research Electronics) and by Uniden.  Personally, I don't
 recommend Trident nor many of the AOR brand scanners,
 although the AR8000 and AR3000 have good reputations and
 the AR5000 works well.

 Programmable (synthesized) units have replaced crystal
 controlled models as they don't require crystals and
 usually have a keypad that permits you to store frequencies
 into channels.  Programmables are now so cheap it doesn't
 make sense to buy a crystal unit as your main scanner
 unless you get it for under $45 or so.

 You can get a battery operated hand held scanner, a bigger
 "base" scanner which is powered from an AC outlet, or a
 mobile scanner which connects to your auto's electrical
 system.  There are tradeoffs -- base and mobile scanners
 have larger displays and almost always provide more audio
 than portables, and some portables are more prone to
 interference when connected to outdoor antennas than base
 models.  But when severe weather knocks out the power in
 your home, there's nothing like having a battery operated
 scanner to monitor the power utility and police

 Make sure your first scanner has a "search" feature, which
 allows it to search all the frequencies between two
 frequency limits of your choosing.  Beware of low cost
 programmables which can't search.  Some models, like the
 early Uniden SportCats and Radio Shack PRO-2046, allow
 searching between limits, but the limits are factory
 programmed and cannot be altered.

 Get a model which covers the 800 MHz band.  Usage of the
 800 - 950 MHz band is growing fast and you will miss out on
 the action unless your scanner covers this band.

 If you're not sure whether you'll like scanning, don't want
 to spend much money, a 50 channel scanner will do.  In
 general, the more channels and banks, the better.

 Most of the action takes place on frequencies between 30
 and 1000 MHz, so don't be misled by scanner models boasting
 coverage from 3 to 2000 MHz.  There's currently not much to
 monitor in the 1000 - 2000 MHz range.

 If you are interested in receiving short wave, that is,
 signals in the 3 - 30 MHz range, it's best to get a short
 wave radio specifically designed for that purpose.
 Although some scanners receive the short wave band, their
 performance in that range is often second rate.  The $1500
 Icom R8500 and $2000 AOR AR5000 models are exceptions.

 Deluxe scanners can be controlled and/or downloaded by a
 personal computer, a feature which appeals to a small but
 growing number of scanner owners.

 Almost all low and mid-priced scanners are prone to
 receiving images -- receiving the same signal erroneously
 on two or more frequencies.  With a few exceptions, images
 are unwelcome due to the interference they cause, e.g.,
 hearing aircraft transmissions while the scanner is tuned
 to the local police frequency.  Premium quality scanners
 use "up conversion" circuitry, a scheme which greatly
 reduces, but does not eliminate, image reception.

 Currently, the more popular scanners include the
 discontinued Radio Shack PRO-2042 and PRO-2006
 base/mobiles, the Uniden/Bearcat BC780XLT, BC895XLT,
 BC245XLT, SC200, and Radio Shack PRO-92 and PRO-94
 portables.  A number of owners report problems with the
 Icom R1 portable and the older Uniden/Bearcat 8500XLT base
 and 2500XLT portable.  The Uniden BC9000XLT base and
 BC3000XLT portable work very well.  The ICOM IC-R2 and
 Yaesu VR-500 are the two smallest "pocket" scanners which
 perform.  Both are tiny enough to fit comfortably in a
 shirt pocket so you can monitor without attracting undue

 Looking for value?  At $170 discount price, the 100 channel
 Uniden/Bearcat BC278CLT base is a good value and available
 at most Sears and Best Buy stores.  The Uniden Sportcat
 SC200 portable performs very well is an excellent value at
 its $220 street price.

             CTCSS and DCS Tone Squelch Feature

 Upscale scanners can be optioned with a subaudible tone
 decoding squelch circuit.  There are two types: CTCSS
 (Continuous Tone Coded Squelch System) and DCS (Digital
 Coded Squelch).  In simple terms, this feature lets your
 scanner ignore signals you don't want to hear.

 Most land mobile two way radios, except trunked systems,
 transmit either CTCSS or DCS signals subaudibly along with
 the voice information.  U.S. military field radios employ
 wider deviation and a 150 Hz CTCSS tone, not supported by
 most scanners or CTCSS decoders.

 There are over 40 different CTCSS codes and you can program
 a specific CTCSS or DCS code into each memory channel.
 Using a CTCSS or DCS decoder permits your scanner to open
 the squelch only if the transmission has a code which
 matches the code you program.

 CTCSS and DCS decoding offers several advantages:

   1.  Ignore unwanted signals on shared frequencies: It is
       common for several users to share the same frequency,
       e.g., my county sheriff uses the same frequency as
       Chicago Police, located about 60 miles away.  I want
       to hear my sheriff's transmissions but don't want the
       scanner to stop on or listen to Chicago Police
       transmissions.  This is especially a problem when
       radio propagation is good, e.g., during a "band
       opening," when reception range is temporarily

   2.  Combat intermodulation interference: Helps keep out
       intermod and image interference from strong pagers
       and other signals which are not transmitted with a
       matching code.

   3.  Ignore scrambled transmissions: Many federal law
       enforcement agencies (FBI, Secret Service, etc) and
       some local police agencies employ digital voice
       scrambling, which sounds like white noise and is
       annoying to hear.  The CTCSS or DCS code is sent only
       when the station is transmitting unscrambled, or "in
       the clear."  You can program federal frequencies
       along with the proper code into your decoder-equipped
       scanner so you won't have to listen to the scrambled
       mess and only hear their transmissions when they are

 CTCSS also goes by various tradenames: Motorola's PL
 (Private Line), GE's Channel Guard, and RCA's Quiet
 Channel.  Motorola uses the tradename DPL (Digital Private
 Line) for its digital coded squelch.

      How Do I Determine the Proper CTCSS or DCS Code?

 There are a few ways to determine the CTCSS or DCS code
 transmitted by a station:

  1.  Use an outboard CTCSS/DCS reader which must be
      attached to the discriminator output circuitry inside
      the scanner.  The reader has an LCD or LED display
      which indicates the code when a station transmits.  I
      use a CSI model CD-1 Communications Decoder Unit, an
      an excellent reader which sells new for about $200.
      (Connect Systems Inc., Ventura, CA, 800-545-1349,
  2.  Many of the ScannerMaster guides, as well as scanner
      club newsletters, print the CTCSS codes used by
      transmitting stations.
  3.  On some scanners equipped with the CTCSS squelch, you
      can program into memory the frequency of interest.
      Then you "tune" slowly through all the different CTCSS
      and/or DCS codes until the squelch opens and you hear
      the dispatcher talking.  This is a slow process and
      the station has to keep transmitting during it.
  4.  A slow, brute force method is to program the same
      frequency but a different CTCSS code into several
      channels and see where your scanner stops.
  5.  In some cases, I've actually examined the walkie-
      talkies I want to monitor and found the CTCSS code
      printed on a label on or inside the radio.

                      Scanner Antennas

 All scanners come with a built in antenna, permitting
 reception up to about 20 miles or so.

 Portable scanners are supplied with a helical (spring
 shaped) antenna, covered by rubber.  The rubberized
 antennas furnished with current models are too stiff and
 place stress on the antenna jack.  Older scanners to be
 supplied with more flexible antennas.  I prefer these
 alternative antennas for use with portable scanners:

  1.  The Icom FA-1433B dual band flex antenna, a thin and
      very flexible rubber antenna, is slightly longer than
      a stock heliflex but provides better performance.  The
      Premier (Prime) RD-9 and RD-9SMA are about the same
      length but even thinner.
  2.  The Austin Condor is a 12" long rubberized antenna
      available for about $30.  While considerably longer
      than the stock antenna and the FA-1443B, the Condor is
      very flexible and provides VHF-high band reception
      superior to both.  It is not designed to cover the
      VHF-low band, but will allow reception there at least
      as good as shorter antennas.  The Austin Condor is
      available from Grove Enterprises.
  3.  The "Thin-Stick" is an 18 inch telescoping antenna for
      extended range.  It is made in USA by Smiley Antenna
      Co., Inc. and is designed to cover both the 2 meter
      and 220 MHz bands, but its variable length means it
      can be adjusted for optimum performance on other
      bands.  What makes the Thin-Stick different from an
      ordinary telescoping antenna is the spring between the
      antenna and the connector portions.  The spring
      absorbs most of the impact if the antenna collides
      with an object.  The street price is about $17 and it
      is available from Amateur Electronic Supply, Milwaukee
      and other retailers.

 Outdoor antennas, like the Channel Master 5094A (available
 from Amateur Electronic Supply) or Antenna Specialists AV-
 801 (recently discontinued), can extend reliable reception
 to 50 miles or more, depending on terrain.  If you do use
 an outdoor antenna, be sure to disconnect and ground it
 during storms and when not in use to avoid a lightning
 hazard.  Discone and ground plane type antennas can be more
 prone to cause scanner damage due to static charge buildup
 because they are not at "DC ground."

                   Coaxial Cable Feedlines

 If your antenna installation requires more than 50 feet of
 feedline, use RG213/U or high quality RG8/U coaxial cable.
 RG213/U, e.g., Belden type 8267, has a non-contaminating
 jacket and will last longer.  Each has an outer diameter of
 about 13/32".  Similarly sized Belden 9913 cable and clones
 have lower attenuation but are difficult to bend, require
 special connectors, and can accumulate moisture inside
 because they are hollow.

 If you must use a small diameter cable for long runs, use
 RG6/U.  Avoid RG58/U (7/32" OD) due to its losses at high
 frequencies.  RG8/X (1/4" OD) is suitable for short patch

                 Where Can I Buy A Scanner?

 Almost every community has at least one Radio Shack store,
 and you can find scanners there.  Be sure it is on sale, as
 Radio Shack list prices are high and their scanners are
 offered at reduced prices by mail order discounters.

 Discount chain stores like Wal-Mart, Best Buy, K-Mart,
 Service Merchandise, and Circuit City sell scanners, but
 carry just a few models.  Department stores, like Sears
 Roebuck and Montgomery Wards, sometimes offer low end
 scanners, although at high prices.

 The best buys on new scanners are from reputable mail order
 radio dealers, for example:

    - Grove Enterprises, 7540 Highway 64 West, Brasstown, NC
      28902.  For a free catalog, call (828)837-9200.
      Telephone (orders only): (800)438-8155.  Web page is

    - National Electronics (formerly National Tower
      Company), PO Box 15417, Shawnee Mission, KS 66215.
      Telephone (800)762-5049, (913)888-8864.  Web page is

    - The Ham Station, 220 N. Fulton Ave., Evansville, IN
      47719-0522.  Telephone (800)729-4373, (812)422-0231.

    - Scanner World (Albany, NY). Telephone (518)436-9606.

    - Amateur Electronics Supply (Milwaukee, WI). Telephone
      (800)558-0411.  Web page is

 Beware of inflated "shipping and handling" charges and be
 sure to include these when comparison shopping.

 Used scanners may be found at hamfests, flea markets,
 garage sales, or listed in the classified advertisement
 section of your newspaper.

                   Modifying Your Scanner

 The term "mod" is often used as shorthand for
 "modification."  If you are handy with a soldering iron,
 you may be interested in modifying ("modding") your scanner
 to add features or enhance its performance.  Be warned this
 usually voids your warranty and current models are
 difficult to service due to the small, delicate surface
 mount components.  Modifying any scanner to receive
 cellular phone signals is now considered illegal.  By
 federal regulation, new scanner models must be designed to
 they cannot be easily modified to tune the cellular phone

 The term "mod" has been narrowly used by some people to
 mean a change which permits a scanner to receive cellular
 phone frequencies.  This definition is far too restrictive
 as there are several ways one could modify a scanner, e.g.,
 changes to improve audio quality, adding an S-meter,
 expanding the number of channels, changing the earphone
 jack to accept stereo headphones, etc.

 Modification article files can be copied from several ftp
 sites including the /pub/hamradio/mods directory at:
 (IP address

 Modification articles posted on Usenet seem to have a life
 of their own.  Frequently, they are plagiarized from the
 Internet and compiled by book, CDROM, and magazine
 publishers, sometimes reworded, then sold.  Hobbyists then
 copy the modifications from the books, CDROMs, and
 magazines back onto the Internet or BBSs (bulletin board

 Grove Enterprises and other companies advertise a
 warranted, modification for fee service.

                    Scanner Repair Shops

 Is your scanner broken?  Aside from sending the scanner
 back to the manufacturer for repair, here is one company
 which repairs scanners:

    - G & G Communications (telephone 716-768-8151) -
      ( or email
      or This family owned company repairs
      scanners and pagers and stocks parts for several older
      models.  G & G cannot usually repair AOR scanners due
      to lack of manufacturer support.  G & G sells and
      sometimes buys old scanners and parts, too.  They are
      located at 7825 Black Street Rd., LeRoy, NY 14482.

 Repair tips for Bearcat and Radio Shack scanners are
 discussed in two other FAQ articles.

          Where Can I Obtain Frequency Information?

 To avoid chaos, the FCC licenses two-way radio users and
 assigns them specific frequencies.  Groups of frequencies
 are allocated to specific types of users, so you won't
 usually find fire departments using the same frequencies as
 taxi drivers, for example.

 Scanner enthusiasts can obtain frequency information from
 several sources, including books, government microfiche
 records, or other listeners.

 Books: The most convenient source of fire, police, and
 local government frequencies is Gene Hughes' Police Call
 Plus, published each year in 9 regional volumes by Hollins
 Radio Data, and sold at Radio Shack and larger book stores.
 The newest editions contain abbreviated business listings,
 too, although callsigns and other details are listed only
 for local government and public safety licensees.

 I also recommend the book, Monitor America, published by
 SMB Publishing (now known as Scanner Master Publishing),
 and available from Grove Enterprises for about $30.  A 1100
 page 3rd edition is now available.  Monitor America
 contains several pages of police, fire, local government,
 news media, sports, federal government, and commercial
 broadcast frequencies for all 50 states.  It contains
 detailed communications system profiles and precinct maps
 for major metropolitan areas.  Police and fire radio codes
 and unit identifiers unique to local agencies are listed
 for several cities.  This differs from Police Call, which
 gives a more sterile, but uniform treatment of licensees,
 listing even the smallest of towns.

 Uniden has published several regional directories using the
 "Betty Bearcat" name, although there are much better
 directories available from Scanner Master (Newton
 Highlands, MA, tel. (508)655-6300) for some regions.

 The most readily available source of sensitive US
 government frequencies is still Tom Kneitel's Top Secret
 Registry of US Government Radio Frequencies.  Published by
 CRB Research, the 8th edition is available from Grove
 Enterprises for about $22.  Kneitel's book contains
 frequency listings for NASA, military, FBI, Secret Service,
 DEA, IRS, Border Patrol, arsenals, ammunition plants,
 missile sites, and others in the 25 to 470 MHz range.

 Tab Books Master Frequency File, first edition, written by
 James Tunnell and Robert Kelty, lists federal agencies and
 frequencies and deserves a read.  However, there are no
 military listings and many pages are devoted to appendices
 and references which contain no frequency listings.  The
 space would be much better used by a combined federal
 frequency list sorted by frequency.

 Commercial Magazines: Although national in circulation,
 local frequency information is sometimes available in
 Grove's Monitoring Times (tel. 828-837-9200, and the sensationalistic Popular
 Communications, (tel. 516-681-2922).  National Scanning
 (NatScan) is a national scanner magazine published
 bimonthly and is affiliated with Uniden's Bearcat Radio
 Club.  The best scanner frequency lists are often found in
 club publications, not commercial magazines, and are
 discussed later.

 Government Records: Every year, the US Government sells FCC
 license information, in the form of microfiche, floppy
 disk, and magnetic tape, to the public through the US
 Department of Commerce National Technical Information
 Service (NTIS).  The high cost of buying government records
 limits their appeal to hardcore enthusiasts.  You can write
 for a catalog of FCC Master Frequency Database items to the
 NTIS, 5285 Port Royal Road, Springfield, VA 22161.

 The FCC has an agreement with PerCon (tel. 716-386-6015), a
 private company, to sell FCC license information to the
 public on CDROMs.  You can buy the full license information
 for a multi state region or a less detailed license
 database covering the the entire USA on CDROM.  The PerCon
 Spectrum CDROM sells for under $29 and contains a handful
 of fields for every FCC license in the US.  The Spring 1995
 edition works in DOS, Windows, and Mac environments.

 Grove enterprises sells FCC license information on CDROM,

 As I have already done for hundreds of radio enthusiasts,
 companies, government agencies, and organizations across
 the country since 1994, I will locate FCC licensed and
 selected FAA and CAP transmitter sites in an area of your
 choice, in any state, and produce a custom RadioMap(TM)
 report, including a beautiful 11" by 17" scaled color map,
 protected by plastic.  The map is marked with transmitter
 sites, cities, highways, airports, military installations,
 national parks, etc.  See
 for a sample.

 RadioMap has been advertised monthly in Monitoring Times
 magazine since 1995.  The graphical nature of RadioMap
 allows you to identify antenna sites and visualize the
 transmitter locations in your neighborhood, near your
 office, and other places of interest -- from VLF through
 microwave.  The report lists frequencies, callsigns, and
 licensee names.  RadioMap covers police, fire, local
 government, TV, business, industry, common carrier,
 railroad, trucking, and many more types of transmitter
 sites, excluding ham radio stations.  Wireline and
 nonwireline cellular phone and AM/FM broadcast transmitter
 sites are clearly marked using unique color icons.

 Industrial customers use RadioMap reports to survey the
 "radio environment" prior to installation of radios and
 wireless microphones at customer sites.  RadioMap is used
 by the maritime and broadcast industries, as well as ham
 radio operators to solve intermod interference problems,
 and has been very favorably reviewed in RCMA Scanner
 Journal, American Scannergram, and USSN.

 The RadioMap processes and software are unique and
 proprietary.  Unlike "more tame" maps, RadioMap shows the
 locations of military bases, ammunition plants, arsenals,
 weapons factories, and other military installations.

 For a flat fee, you choose the center location, and I
 choose the range, depending on transmitter site density:

         suburbs: 5 mile range (100 sq. mi. area)
         rural areas: 10 or more miles (400 sq. mi. area)
         dense urban area: 1 - 2 mile range

 Longer ranges for additional charge - call for pricing.

 A custom RadioMap report costs $24.95 plus $5.00 shipping
 and handling.  For an additional $10.00, the deluxe report
 includes an extra index sorted by frequency and a custom
 frequency allocation histogram, a 0 - 1,000 MHz "spectrum
 analyzer-like" display showing spectrum usage by the
 transmitters in the map coverage area.  Send check or money
 order payable to Bob Parnass for $29.95 for standard or
 $39.95 for deluxe RadioMap report with histogram and
 additional index by frequency.  Include your name, address,
 and telephone number, along with center location (nearest
 intersection of 2 streets, or latitude & longitude) and
 mail to: Bob Parnass, 2350 Douglas Road, Oswego, IL 60543.
 tel. (630)554-3839 6-10 PM central time.  For a brochure,
 send SASE.

            Do Your Own Frequency Detective Work

 When you try listening to a frequency for the first time,
 you'll want to know who you're hearing.

 Although FCC rules require radio systems to identify their
 operations with their assigned call letters either
 automatically or verbally, most ignore the regulation.
 This often makes it difficult to know who is transmitting.
 Moreover, many radios are now being placed in service
 illegally, without first obtaining the required FCC

 There is a challenge in deriving new spectrum usage
 information on your own.  Sometimes it requires several
 days of listening, taping, and compiling fragments of
 information.  Other times, the frequency information is
 there for the taking - without hassle.

 You can approach from two directions:

   1.  Listen first: Monitor a frequency or frequencies, and
       try to determine who's transmitting and what purpose
       the channel serves.  Once you identify the user, log
       the information.

   2.  Compile first: Take advantage of opportunities, such
       as examining the frequency label on a guard's radio,
       or reading the FCC license hanging on the "radio
       room" wall, to compile frequency lists, then monitor
       the listed frequencies to confirm that they are
       really in use.  Readers are urged to abide by the
       rules of good taste and local laws in the quest for
       frequency information.  Don't trespass, wait for an

 Most listeners use a combination of both approaches.

 You can examine the FCC license on premise.  I have found
 the actual FCC radio license, complete with frequency
 assignments, hanging on the walls of places like the mall
 security office or company guard shack.  You can examine
 the labels on radio equipment.  Frequency information is
 engraved on labels on the back of many walkie-talkies, or
 inside the battery compartment, like in the Motorola HT220
 model.  Most pagers have labels on the bottom or inside.
 Like passwords taped onto terminals, it's not uncommon to
 find labels embossed with frequencies or call letters glued
 to the front of base stations.

 You can make your own opportunities for eyeing the
 equipment or take advantage of "open house" events.  If
 information is displayed publicly, then a reasonable person
 could assume it's not government secret.  Hobbyists are
 urged to exercise a modicum of restraint and good
 judgement, however.

                   How Can I Use Equipment
                 to Uncover New Frequencies?

 If you don't know the exact frequency, but have a general
 idea of the range (e.g. 150 - 152 MHz), use your scanner's
 "search" mode.  Most programmable scanners afford the
 ability to search between two frequency limits set by the
 user.  A few models, like the ICOM R7000/R7100, and R1, and
 older Bearcat 250 and Regency K500, have the ability to
 automatically store active frequencies found during an
 unattended search operation.

 To find the frequency of a hotel communications system, one
 fellow installed his Bearcat 250 in his car and parked in
 the hotel lot, leaving the scanner in the "search and
 store" mode.  He left the antenna disconnected so the
 scanner would only respond to a transmitter in the
 immediate vicinity.

 Aside from a scanner and antenna, the most useful piece of
 equipment for sleuthing is a voice actuated (VOX) cassette
 tape recorder.  You don't need a high fidelity model or
 anything fancy, a Radio Shack CTR-82 will do.  It's best to
 use a shielded, attenuating cable to feed the scanner audio
 into the recorder rather than relying on the recorder's
 internal microphone.

 VOX recorders allow one to compress a whole day's worth of
 monitoring onto a single tape.  I often leave a recorder
 "armed" and connected to a scanner at home while I am at
 the office or doing something else.  When call letters are
 mumbled, I can play and replay the tape until I hear and
 understand them.

 Test equipment can aid in the quest for new frequency
 information.  I've used a spectrum analyzer connected to an
 outside antenna, and a frequency counter for close-in work.

        Are There Any Scanner Clubs or Mailing List?

 One of the best parts of the hobby is sharing it with other
 radio buffs.  Trading information with other hobbyists
 about frequencies, communication systems, and receiving
 equipment is more valuable than any pile of magazines.

 Clay Irving <> administers a scanner
 electronic mailing list, called "scanning."  To subscribe,
 send an Email message to:

 In the body of the Email message, put: subscribe scanning

 Other scanner mailing lists include:,,, and

                    All Ohio Scanner Club

 A smaller club is the All Ohio Scanner Club.  Its bimonthly
 publication, The American Scannergram, is about 60 pages
 long.  Although concentrating on Ohio and the Northeastern
 states, there is frequency information from other states,
 and plenty of good product reviews and scanning tips.

 Annual dues are $18.50 and more information is available

               Dave Marshall, Managing Editor
               All Ohio Scanner Club,
               50 Villa Road,
               Springfield, OH 45503.

          Chicago Area Radio Monitoring Association

 The Chicago Area Radio Monitoring Association (CARMA) is
 the foremost club for scanner radio hobbyists in the
 northern Illinois area.  CARMA was formed from the Chicago
 chapter of the Radio Communications Monitoring Association
 (RCMA), and we have been meeting since the early 1980s.

 Many CARMA members are active in ham radio and GMRS, but
 the club is devoted to scanning and scanners.

 Meetings are held on Saturdays, many at area restaurants,
 about 6 times a year.  Although lunch starts at noon, the
 meetings begin officially at 1 PM and often run until about

                           - 2 -

 4 PM.  You must purchase a lunch since we get the room for
 free.  Meetings consist of a quick review of club business,
 sometimes a special presentation, and a "round table"
 discussion/question & answer session.  Large quantities of
 information and frequency lists are often distributed in
 the form of free handouts.  Members often sell radio
 equipment at the meetings, too.

 In addition to regular meetings, there are two CARMA
 picnic/field days during which members meet at a park,
 erect antennas, eat, and operate scanners from battery
 power.  CARMA members take organized tours of various
 communications facilities in the area.

 Club meeting dates and times are published on the CARMA
 email list,  You can obtain a free
 electronic subscription to the CARMA email list.  For more
 info, see:


 The club's mailing address is:

                     P.O. Box 2681
                     Glenview, IL 60025

 Most meetings are be held on Saturdays at Phillies Pizza,
 6300S. Kingery Highway, located in the shopping center at
 the corner Rt. 83 and 53rd St. in Willowbrook, IL.

Bob Parnass, AJ9S                              

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Last Update March 27 2014 @ 02:12 PM