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BUYING A USED SCANNER RADIO
by Bob Parnass, AJ9S
[NOTE: 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/
group/rec.radio.scanner.]
Abstract
This article discusses the purchase of used scanner radios
and includes these topics:
1. Motivation for buying a used scanner
2. A used scanner may be a broken scanner - where to get
it fixed
3. Evolution of the scanner
4. Obtaining crystals
5. Keyboard programmable scanners
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.
Introduction
Anybody with enough money can buy a brand new scanner, but
you can save lots of money if you get a good deal on a used
scanner. Hamfests are probably the best place to find used
radios, but you must be familiar with the equipment.
Hamfests are repleat with older radios you won't see in
today's catalogs.
At last count, there were over 140 scanners and monitor
receivers of various brands in my collection. I purchase
most of my receivers at hamfests or horsetrade with other
radio hobbyists.
Uniden sells refurbished scanners dn you can check current
inventory at their web site:
http://www.uniden.com/docs/store
A Used Scanner May be a Broken Scanner
Getting a bargain is not without some risk. I have had
sellers look me square in the eye and tell me their radio
worked fine -- when it really didn't.
Buying a used portable scanner is riskier than buying a
mobile or base model. Portable scanners are subject to more
physical abuse and many have been dropped. If a radio has
been dropped, the laws of probability dictate that the first
point of impact was probably a corner, so be sure to examine
each corner for evidence of trauma.
Scanners used in mobile service are subject to vibration,
dust, and temperature extremes. This shouldn't dissuade you
from buying a used mobile scanner, but be aware of possible
complications.
You should have some recourse if the radio you buy turns out
to be defective. For hints on fixing older Bearcat base
scanners, see "Tips for Fixing Bearcat Scanners," by Bob
Parnass, AJ9S, in March 1996 Monitoring Times magazine,
published by Grove Enterprises, http://www.grove-ent.com
If you can't fix the radio yourself, you can pay to have the
manufacturer or a service clinic repair it for you. Radio
Shack repairs scanners, and Uniden can repair newer Bearcat
models but often refuses to service older models, claiming
they are "unrepairable" and carving the letter "U" on the
cabinet.
G & G Communications (telephone 716-768-8151) is a family
owned company which repairs scanners and stocks parts and
crystals for several older models. They usually don't
repair AOR scanners due to lack of manufacturer support.
They are located at 7825 Black Street Rd., LeRoy, NY 14482.
(http://www.iinc.com/ggcomm/ or email ggcomm@iinc.com or
ggcomm@aol.com)
The re-incorporated Electra Corporation, (317)326-4419, is
able to effect repairs on some older (pre-Uniden) Bearcat
scanners. They sell crystals, antennas, power cords,
owner's manuals ($11 ea). Electra Corporation is located at
251 N. 300 W. Greenfield, IN 46140-8496.
You may be able to obtain manuals for older Midland scanners
from:
Midland Consumer Radio Products
1670, North Topping,
Kansas City,
MO: 64120
Phone: 816-241-8500
Evolution of the Scanner
It helps to understand some scanner history before shopping
for a used scanner. You will likely see radios from many
vintages at a hamfest, and should avoid buying early units
unless you are a scanner collector.
One of the earliest ancestors to the scanner was the
converter. Manufactured by Tompkins (Tuneaverter),
Petersen, Bearcat (Lil Tiger), Midland, and others,
converters were made to operate in conjunction with AM
radios. Then came wide band monitor receivers, in both
tunable and crystal control models, like the Radio Shack
PRO-2B. Truthfully, converters and tuneable FM receivers
are interesting but don't work well by today's standards.
While tuneable receivers were in vogue, solid state
technologies supplanted tubes. Better performing, narrow
band crystal controlled units, like the Sonar FR-105,
followed. These units did not scan, rather channel
selection was accomplished using a simple rotary switch.
Sonar even made a 24 channel unit, model FR-2513, in which
crystals were held in a rotary "turret."
The earliest scanners, like the 1968 vintage Bearcat BCH,
BCL, and BCU models, did not provide individual channel
lockout capability. Electra didn't use the term "scanner"
and instead called these innovative radios "business
receivers." Other models, like the SBE Sentinel, employed a
"Channel 1 Bypass" switch so a user could lockout channel 1.
The first scanners came in single band models, followed by
multiband models. As two-way radio users started to
populate the 450 - 470 MHz band, consumers were forced to
pay a premium for UHF scanner coverage. Some multiband
scanners, like the Electra's Bearcat III, required an
optional circuit board for each band.
There were scanner mutations, designs which never evolved --
odd combinations of AM broadcast receivers with VHF-FM
receive capability, like the flamboyant turquoise Sonar
Sentry FR-103 portables, Electra's Jolly Roger, and GE's
Surveyor series (see US patent 4,011,515, granted 3/8/77).
Lafayette Radio Electronics offered a few CB transceivers
with VHF receiver capability. These poor performers didn't
interest consumers of that era and you should avoid these
models unless you are a scanner collector.
The first programmable (crystal-less) scanners were
difficult to program. Users had to look up frequencies in a
code book and tediously program the information into the
scanner in binary form. Some models, like the Tennelec
MCP-1 (see US patent 3,961,261, granted 6/1/76), Bearcat
BC-101 (see US patent 4,179,662, granted 8/4/78), and Radio
Shack COMP 100, resembled Altair or PDP-8 computers, with a
row of 16 or so toggle switches. Instead of toggle
switches, the Regency WHAMO-10 was programmed by breaking
teeth from metal combs. See US patent 4,057,760, granted
11/8/77. The GRE-manufactured SBE Optiscan (and its Sears
clone) required poking or covering a series of holes in
plastic cards which were then inserted into a slot on the
front panel.
Keyboard Programmable Scanners
Both Bearcat and Regency, as well as Radio Shack offer some
good models. I would avoid the Bearcat 100, and older
scanners made by AOR, JIL, Fox, Tennelec, and Robyn.
Scanner features often differ not only by model but by
manufacturer. For instance, most Radio Shack and Bearcat
programmables allow enable/disable of the delay function on
a per-channel basis. Older Regency units permit the delay
to be enabled/disabled only globally, that is, for all the
channels at one time.
All the older Radio Shack scanners were made by General
Research Electronics (GRE). Uniden began making scanner
models for Radio Shack in the late 1980s, and now supplies
about half the Radio Shack scanners. The older GRE-made
models scan a bit slowly and have a higher level of
synthesizer noise. Most have too much hysteresis in the
operation of the squelch control, but this can be fixed
completely by replacing one resistor. Good, detailed shop
manuals are available for Radio Shack units for $5 - $12.
In the name of cost cutting, some models have done away with
the concept of a "channel bank", i.e. the ability to
select/deselect a group of channels at a time. The bank
concept was a good one. It may be inconvenient to operate a
30 channel scanner without banks (e.g. Regency MX3000,
HX1000) if you operate the way many scanner hobbyists do.
If you want to buy an American-made scanner, you will have
to buy an old model. Until the mid 1980s, rivals Regency
and Electra (Bearcat) built most of the scanners in their
Indiana and Puerto Rican factories. Uniden, a large
Japanese electronics company, purchased the scanner product
lines of both competitors and moved production to Asia.
My favorite VHF/UHF receivers are the the Uniden/Bearcat
BC9000XLT, the 400 channel Radio Shack PRO-2005 and PRO-
2006, and the ICOM R7000, R7100, and R8500. The ICOM models
are more "communications receiver" than a conventional
scanner.
For portable use, I prefer the ICOM IC-R2, Uniden/Bearcat
BC3000XLT, and older Radio Shack PRO-43.
Obtaining Crystals
If you do purchase a crystal controlled scanner or monitor
receiver, you will probably want to buy more crystals to
cover local frequencies.
Scanner crystals may be ordered at your local Radio Shack
store. Each Radio Shack store has a book containing
frequencies and stock numbers. The crystals are mailed to
your home within 10 days.
You can also order scanner crystals from one of the
companies below. Be sure to specify the operating frequency
you want and the brand and model of scanner.
Some companies may ask you to send a schematic of the
scanner or require more detailed information, like series or
parallel resonance, load capacitance, etc.
Crystals for Bearcat and other models are available from:
American Crystal Co.
1623 Central Ave.
Kansas City, KS 66102
tel. 913-342-5493
Bomar Crystal Company
201 Blackford Ave.
Middlesex, NJ 08846
tel. 908-356-7787
Cal Crystal Lab Inc.
1142 N. Gilbert St.
Anaheim, CA 92801
tel. 714-991-1580
International Crystal Mfg Co.
11 N. Lee Ave
Oklahoma City, OK 73102
tel. 405-236-3741, 800-725-1426
G & G Communications
9247 Glenwood Drive
LeRoy, NY 14482.
tel. 716-768-8151
Jan Crystals
Box #-6017
Fort Myers, FL 33911
tel. 941-936-2397
Monitor Crystal Svc
124 W Walnut St Watseka, IL 60970
tel. 815-432-5296
Short product summaries for over 70 scanner models appear in
a separate article, entitled "Scanner Radio Review Briefs."
You may share information with scanner collectors via the
"vintagescanners" mailing list at:
http://www.onelist.com/group/vintagescanners
For more information about old scanners, see:
1. "Confessions of a Scanner Collector," by Bob Parnass,
Monitoring Times, August 1988.
2. "Scanner Collector Primer," by Bob Parnass,
Monitoring Times, May 1995.
--
==============================================================================
Bob Parnass, AJ9S parnass@bell-labs.com
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