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From: [email protected] (Bob Parnass, AJ9S)
Newsgroups: rec.radio.scanner,alt.radio.scanner,rec.radio.info
Subject: Introduction to Scanning
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Date: 1 Jun 2001 13:03:16 GMT
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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 rec.radio.scanner, alt.radio.scanner, and
rec.radio.info. It is also available electronically from
the rec.radio.scanner ftp archive on the official USENET
FAQ library ftp://rtfm.mit.edu/pub/usenet-by-
group/rec.radio.scanner.]

The author writes a monthly "Scanner Equipment" column for
Monitoring Times magazine, published by Grove Enterprises,
http://www.grove-ent.com 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
frequencies.

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. http://www.grove-ent.com

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
frequencies!

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
attention.

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
increased.

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
unscrambled.

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,
http://www.connectsystems.com).
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
cords.

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
http://www.grove-ent.com

- National Electronics (formerly National Tower
Company), PO Box 15417, Shawnee Mission, KS 66215.
Telephone (800)762-5049, (913)888-8864. Web page is
http://www.sound.net/~ne/

- 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 http://www.aesham.com

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
bands.

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:

garfield.catt.ncsu.edu
oak.oakland.edu (IP address 141.210.10.117)

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
systems)!

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) -
(http://www.iinc.com/ggcomm or email [email protected]
or [email protected]) 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,
http://www.grove-ent.com) 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,
too.

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 http://www.megsinet.com/~parnass
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
license.

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
invitation.

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 <[email protected]> administers a scanner
electronic mailing list, called "scanning." To subscribe,
send an Email message to: [email protected]

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

Other scanner mailing lists include: [email protected],
[email protected], [email protected], and
[email protected].

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
from:

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, [email protected]. You can obtain a free
electronic subscription to the CARMA email list. For more
info, see:

http://www.qth.net

The club's mailing address is:

CARMA
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.

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Bob Parnass, AJ9S [email protected]