parnass@ihu1h.UUCP (Bob Parnass, AJ9S) (04/25/86)
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HOW DO YOU FIND THESE FREQUENCIES?
Books, Magazines, Government Records, and Clubs
Bob Parnass, AJ9S
I am often asked, "How do you find these frequencies?"
Scanner enthusiasts can obtain frequency information
from several sources, including books, government
microfiche records, or other listeners.
Books
The most convenient source of fire and police frequen-
cies is the Police Call Radio Guide, published each
year in 9 regional volumes by Hollins Radio Data, and
sold at Radio Shack and larger book stores for about
$7. Police Call is basically a computer printout of
FCC license information in the fire, police, local
government, and conservation services in two lists: by
licensee name within state, and by frequency. Later
editions have included a few pages of local airport and
nonsensitive federal government frequencies.
I highly recommend Richard Prelinger's new book, Moni-
tor America, published by SMB Publishing, and available
from Grove Enterprises for about $15. This single edi-
tion contains 582 pages of police, fire, local govern-
ment, news media, sports, national park, and commercial
broadcast frequencies for all 50 states. The informa-
tion was compiled mainly from members of the world's
largest scanning club, the Radio Communications Moni-
toring Association (RCMA). Monitor America contains
detailed communications system profiles and precinct
maps for major metropolitan areas. Police and fire
radio codes and unit identifiers unique to local agen-
cies 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.
The most readily available source of sensitive US
government frequencies is still Tom Kneitel's 168 page
Top Secret Registry of US Government Radio Frequencies.
Published by CRB Research, the 5th edition is available
from Galaxy Electronics (Box 1202, 67 Eber Ave., Akron,
Ohio) for about $15. Kneitel's book contains frequency
listings for NASA, military, FBI, Secret Service, DEA,
IRS, Border Patrol, arsenals, ammunition plants, mis-
sile sites, and others in the 25 to 470 MHz range.
Since the US government no longer offers frequency
information for its own stations, and has never pub-
lished sensitive frequencies, most of the information
in Kneitel's book has been collected from listeners
over the years. It is certainly not complete, nor 100%
accurate, but is the best book in print for this diffi-
cult to obtain information.
Magazines
Although national in circulation, local frequency
information is sometimes available in Grove's Moni-
toring Times and Kneitel's sensationalistic Popular
Communications.
Government Records
Every year, the US Government sells FCC license infor-
mation, in the form of microfiche, to the public
through the US Department of Commerce National Techni-
cal Information Service (NTIS).
These lists contain license information for the indus-
trial (e.g. Illinois Armored Car, Pinkerton's Secu-
rity, Joe's Towing, etc.), highway maintenance, commer-
cial broadcast, aviation, common carrier, and maritime
services, as well as for police and fire. Microfiche
is not for the casual hobbyist, but rather for the
ardent listener, who can easily spend a few hundred
dollars for the fiche, not including the price of a
microfiche reader.
Copies of some of the FCC microfiche files are sold by
Grove Enterprises. Buying from Grove is usually
cheaper than buying directly from NTIS, although Grove
doesn't offer all the files available from the govern-
ment.
Since federal government radio stations are not licen-
sed by the FCC, they are not listed in FCC microfiche.
In 1981, a group of 60 radio hobbyists split a $1300
fee, and obtained 80 microfiche cards of 'sanitized'
information about federal government radio stations
under the Freedom of Information Act (FOIA)1. Only 12
of the 21 information fields for each station were fur-
nished. Fields like "Remarks", which indicate the
exact usage of a channel (e.g. "Sky Marshall's Net"),
and "Bureau", indicating agency subdivision (e.g. TAC
within the USAF), were withheld. These 80 pages of
microfiche are available from Grove Enterprises for
$25. In a step backward, the US Government insists it
will no longer release this type of information - it is
now 'classified'2.
For a reason unknown to this author, the government
recently released a 1984 vintage set of frequencies
allocated to the FAA. Perhaps this was a mistake,
because the information is marked 'unclassified', but
all fields are furnished, including some which indicate
security related usage. Grove sells this set of 33
microfiche cards for about $13.
Radio Clubs
One of the best parts of the hobby is sharing it with
other radio buffs. Trading information with other hob-
byists about frequencies, communication systems, and
receiving equipment is more valuable than a pile of
magazines.
In 20 years of being an amateur radio operator, and
belonging to amateur radio clubs, I never realized
there were any scanner clubs! In 1983, I joined the
world's largest scanner club, the Radio Communications
Monitoring Association (RCMA).
Founded in 1975, the RCMA is the "first national and
international organization of monitor radio listeners."
There are several regional chapters which hold regular
meetings. Club dues are $16.50 per year, which inclu-
des a monthly newsletter of about 95 pages. Although
the focus is on VHF and UHF ranges, there is coverage
of HF utility stations below 30 MHz.
Inquiries about RCMA membership should be sent to:
RCMA General Manager
P.O. Box 542
Silverado, CA 92676
USA
The Scanner Association of North American (SCAN) is a scan-
ner organization headquartered in Chicago. Having no elec-
ted officers or meetings, SCAN is not a club in the tradi-
tional sense, rather it is run by an advertising agency con-
tracted by the manufacturer of Bearcat scanners. The $12
per year membership fee includes SCAN Magazine, a thin,
albeit glossy, bimonthly.
Membership information is available from:
Scanner Association of North America
240 Fencl Lane
Hillside, Illinois 60162
Do Your Own Sleuthing
The real challenge is deriving new spectrum usage informa-
tion. 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.
More about sleuthing will be discussed in Part II of this
article.
Sleuthing
Bob Parnass, AJ9S
Part I of this series discussed how scanner enthusiasts
can obtain frequency information from books, government
microfiche records, or other listeners. This
installment discusses digging up new frequencies on
your own.
Do Your Own Sleuthing
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 frequen-
cies, and 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" wall3, to compile frequency
lists, then monitor the listed frequencies to
confirm that they are really in use.
Most listeners use a combination of both approaches.
What Makes Station Identification Difficult?
In most instances, FCC rules require radio users to
identify their operations with FCC assigned call let-
ters. Police and fire departments, especially those
with trained radio dispatchers, seem particularly con-
scientious about station identification. Like commer-
cial broadcasters, many of these stations identify on
the hour and the half hour.
Some repeater stations have Morse code identification
circuits which transmit call letters on a periodic
basis, insuring compliance with FCC rules.
On the other hand, about half the industrial radio sta-
tions monitored within the last year ignore the FCC
regulation, making it difficult for a listener to know
who he's listening to. Some stations may operate for
years using the nondescriptive "base to mobile 2" or
"Joe to base" protocol. One rung up the hierarchy are
stations that identify using something like "Acme base
to 107", giving the listener a clue for his log. If
call letters are given, they are often rendered unin-
telligible by operators who fail to enunciate. The
failure to identify is more likely due to sloppiness,
rather than any attempt to hide station identity.
While not regulated by the FCC, federal government
radio stations vary in the extent to which they iden-
tify their transmissions. Some federal stations do not
have call letters. A nearby paging transmitter period-
ically transmits a voice recording announcing, "This is
the Army Joliet Ammunition Plant." What more could a
listener ask for?
The following examples illustrate techniques I've used
to derive new frequency information.
Examine the Labels on Radio Equipment
Frequency information is engraved on labels on the back
of many walkie-talkies, or inside the battery compart-
ment, 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 Dymo
tape 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.
- At the annual Glenview Naval Air Station open
house, I examined a military manpack radio being
used by dispensary paramedics. The radio's tuning
__________
1. See "The Government Giveth, the Government Taketh Away",
by Richard Prelinger, in Monitoring Times, July 1982.
2. See "AFIO and the FOIA", by Bob Grove, in Monitoring
Times, September 1982.
3. 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.
- 2 -
dial was set at 34.15 MHz.
- The Illinois Army National Guard proudly displayed
two armored personnel carriers at the local county
fair, each equipped with VHF-FM and HF-SSB tran-
sceivers.
In addition to a tuning control (VFO), the VHF-FM
radio had a set of channel select pushbuttons,
much like those in a car radio. I asked a
guardsman a few questions about the radio, and he
gladly demonstrated the channel preset feature. A
panel above the channel pushbuttons was labeled
with the frequencies: 32.055, 34.45, 35.35,
40.55, and 40.60 MHz.
Hobbyists are urged to exercise a modicum of restraint
and good judgement. In New Jersey, a radio
technician/hobbyist called to service a transmitter in
a county building, noticed a new unattended repeater
installation in the same room. Being curious about
what frequency this repeater was on, he opened the
access door to copy the frequencies from the radio's
crystals. It turns out that this radio belonged to the
US Secret Service, and opening the access door had
activated a "tamper alarm"!
The tech was skating on thin ice. He had nobody's per-
mission to tamper with that equipment.
Equipment to Determine Frequency Usage
If you don't know the exact frequency, but have a gen-
eral 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 lim-
its set by the user. Two older models, the 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 discon-
nected so the scanner would only respond to a transmit-
ter in the immediate vicinity.
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.
How Can I Determine To Whom I'm
Listening? - An Example
While scanning the industrial frequencies in the 150
MHz range, a van driver was overheard communicating
with "base" while driving around my town. The stations
involved never used FCC call signs - this would have
made life a lot easier for me, and legal for them!4
Transmissions were short and infrequent, so it was
decided to tape record all transmissions on this fre-
quency for several days to determine the station's
identity.
During daylight hours, a modified Regency K500 scanner
was left tuned to the target frequency, connected to a
cheap tape recorder through a home built interface.
Using a carrier operated relay, the tape interface sup-
plied power to the recorder only during radio transmis-
sions, so a day's worth of traffic could be compressed
into a 45 minute tape.
Each day, the tape was played back and notes on names,
locations, and activities mentioned during the day's
transmissions were taken. The van driver appeared to
be making daily stops at a local bank and two shopping
malls. A Walgreen's store seemed to be the only stop
at one mall. A few times, "base" ordered the van "back
to the Training Center." There were frequent references
to "guests checking out", "dropping a guest off", and
"instructor[s] missing a class". At times, "base"
spoke with "security", who must have been using a
walkie-talkie as his signals weren't strong enough to
hear.
Was this a hotel? Calls to the three local hotels
revealed that none provides shuttle bus service to the
shopping malls. A call to the Walgreen's, inquiring
about bus service to the store, drew another blank.
During my shopping trips, I began to pay closer atten-
tion to vans with antennas driving through the parking
lots.
I was leaving the mall one day, when a week's effort
paid off. A maroon and white van, equipped with a
VHF-Hi antenna, was dropping shoppers off at
Walgreen's. A sign on the van's door read:
XYZ Central Training Center5
Lisle, Illinois
I watched the driver pick up a microphone, and listened
to him on my portable scanner checking back with his
"base".
All the pieces fit: the "guests", the "classes", the
"instructors". Mystery solved; I had been monitoring
the customer training center for a large computer
manufacturer. The training center has hotel rooms and
dining facilities to accommodate students from out of
state. As a convenience, shuttle van service is provi-
ded to local shopping malls.
Summary
Through books, government records, and radio clubs,
scanner listeners can make use of frequency information
compiled by others. Two-way radio users sometimes fail
to identify their transmissions properly, making it
more difficult for listeners to know who they are moni-
toring. By examining radio equipment labeling, and
monitoring and taping transmissions, scanner
enthusiasts can unearth new information.
__________
4. One may use FCC license microfiche, described in Part I
of this article, to identify stations using call
letters.
5. XYZ is a pseudonym for the actual licensee name.
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Bob Parnass, Bell Telephone Laboratories - ihnp4!ihu1h!parnass - (312)979-5414