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THE RADIO SHACK PRO-2005 PROGRAMMABLE SCANNER
by Bob Parnass, AJ9S
Manufactured in Japan by General Research Electronics,
the Radio Shack PRO-2005 is a 400 channel, wide coverage
scanner radio, incorporating NBFM, WBFM, and AM modes.
It is the successor to the PRO-2004, the super scanner
which put Radio Shack out in front of its competition in
the base station scanner market.
The 2005 is basically a 400 channel PRO-2004, built using
surface mount components, and housed in a smaller pack-
age.
Frequency Coverage
Radio Shack's last minute decision to remove cellular
telephone frequency coverage from the PRO-2004 caused a 7
week delay in its introduction. The PRO-2005 appeared in
the stores promptly on the heels of the 2004 closeout
sale. Both the PRO-2004 and PRO-2005 cover 25-520 and
760-1300 MHz, except for 2 gaps in the cellular telephone
bands. The two gaps in the 800 MHz range can be restored
in either scanner by clipping a diode.
A matrix of diodes, attached to the microprocessor's
input port, is often used to configure radios for sale in
different markets. The diode matrix on new the PRO-2005
is located on the vertical circuit board just behind the
front panel. There are 2 diodes present, and holes
drilled for 2 more.
Lots of Memory
The PRO-2005 has the usual features that scanner buffs
have come to expect: individual channel lockouts,
selectable rescan delay, an external speaker jack, etc.
But, the 400 channel capacity of the PRO-2005 sets
another an industry record, just as the 300 channel PRO-
2004 did! Casual scanner users may scoff at the useful-
ness of having so many channels, but seasoned monitorists
can have those channels filled up in no time flat, espe-
cially with frequencies in the vast 225-400 MHz military
air band, and other federal government allocations.
With so many channels to program, one dreads the thought
of a power failure, which could clear memory in a hurry.
Not to worry, the PRO-2005 memory is backed up by a
- 2 -
conventional 9 volt alkaline battery (not supplied). The
400 channels are divided into 10 banks of 40 channels
each, and one can select or deselect any channel bank
from the scan list. Individual channels can be locked
out in the customary way, but the PRO-2005 maintains the
handy feature introduced in the PRO-2004, a LOCKOUT
REVIEW. Successive depressions of this key step through
the locked out channels.
Scanners worth their keep have a priority feature, with
channel 1 usually designated the priority channel. The
PRO-2005 is more flexible; any of the 400 channels may be
designated the priority channel. When the PRIORITY key
is depressed, that channel will be sampled every 2
seconds, and the radio will stay there if a signal is
heard.
The PRO-2005 has two scan speeds, approximately 8 and 16
channels/second, although one would probably use the fas-
ter speed in most instances. This is the same speed as
the stock PRO-2004, as measured by your reviewer. A
diode could be added to the PRO-2004 diode matrix to
speed up the scan and search rates by 25%. The provision
for extra diodes in the diode matrix makes one hopeful
that the same speedup trick can be applied to the newer
PRO-2005.
When programming a channel, the PRO-2005 firmware sets
the mode automatically, based on its idea of what mode is
most prevalent on that frequency. This feature saves
extra keystrokes, and makes one appreciate the thought
that went into the design of this radio. The default
mode can be overridden easily, if need be, like to listen
to a NBFM satellite in the 225-400 MHz range, which is
mainly populated with AM signals.
Searching
The SEARCH facility found on most programmable scanners
allows the entry of a pair of frequencies, then by press-
ing a key, the radio searches frequencies between those
limits. The PRO-2005 allows for 10 pairs of limits!
These pairs of limits are stored in their own memory, and
don't use up any of the conventional 400 memory channels.
One can set up several search pairs, for instance:
- 46.610-46.970 MHz: cordless telephones
- 144-148 MHz: the 2 meter ham band
- 3 -
- 30.01-30.56, 32-33, 36-37 MHz: US Govt
Another unique feature is the MONITOR key, which stops
the search and stores the frequency in one of ten special
monitor memories. These memories are separate from the
400 main memory channels. The search can be restarted
from where it left off by striking the up or down arrow
key.
The user can select the search direction (up or down),
and step size of 5, 12.5, or 50 kHz, although the PRO-
2005 is intelligent enough to select a default step size
based on the frequencies being searched. As on the PRO-
2004, there is a hidden step size of 30 kHz, but
apparently this step size was disabled when the cellular
telephone frequency coverage was removed.
The selected parameters are displayed on the LCD panel,
smaller than the panel in the PRO-2004. Search speed is
switchable between slow and fast, with fast search being
about 14 increments/second (versus 12 for the
Uniden/Bearcat 800XLT). For a 12.5 kHz increment, this
translates to 11.2 MHz/minute (versus 9.6 MHz/minute for
the 800XLT).
The DIRECT key allows one to start searching up or down
from whatever frequency is on the display. Let's say the
scanner is in MANUAL mode, and set at channel 26, which
contains 460.100 MHz. Striking the DIRECT then UP-ARROW
keys starts the PRO-2005 searching upwards from 460.100.
This is a nice feature.
The PRO-2005 contains a "window detector" circuit, which
is called into play during a SEARCH operation. This cir-
cuit tries to detect when the radio is tuned close to the
center frequency of a station, and prevents the search
from halting prematurely, off to the side of the signal.
The AFC (automatic frequency control) circuit of the
Bearcat 800XLT often causes a search of 850 MHz signals
to halt prematurely. Even though the signal sounds on
frequency, the display reads the wrong frequency. Nei-
ther the PRO-2004 nor the PRO-2005 have this problem.
The PRO-2005 includes a SOUND SQUELCH, resembling the VSC
circuit on the Icom R-7000, which may be used during scan
or search operations. With the the sound squelch
enabled, signified by a red lamp above the pushbutton,
the scanner will skip over unmodulated signals. This is
handy for skipping over "birdies", or link signals with a
constant carrier.
- 4 -
The manual warns that the sound squelch may be fooled by
signals with low modulation, and skip over them. The
PRO-2005 SOUND SQUELCH tries to detect the presence or
absence of modulation (not human speech), so unfor-
tunately, it thinks that noisy dead carriers, digital
data signals, and paging tones are worth monitoring and
will stop the scanner to listen to them.
Taping Facility
A tape recorder can be connected to the TAPE phono jack
on the rear panel, which provides 600 mV of audio at a
10,000 ohm impedance. An audio filtering circuit rolls
off the high frequency components before they reach the
TAPE jack, which makes it impossible to use it for pick-
ing off FM subcarrier signals. In addition to a rear
mounted external speaker jack, there is a miniature head-
phone jack on the front of the scanner.
The PRO-2005 lacks a COR (carrier operated relay) output,
like ICOM R7000 and older Bearcat 300 have, which would
be useful for actuating a tape recorder.
Basic Performance
To evaluate sensitivity, the PRO-2005 was compared with
it's father, the PRO-2004. Since a signal generator was
not used, quantitative measurements could not be made.
Instead, an Antenna Specialists AV-801 antenna was
switched between radios, signals from stations were com-
pared by ear, and the results tabulated.
Simply put, the PRO-2005 proved moderately more sensitive
than the PRO-2004 on most bands tested, and just slightly
more sensitive on a few bands. The cost one pays for the
2005's increased sensitivity is having to put up with
hearing 800 MHz trunked systems and cellular telephone
conversations while searching the 118 - 132 MHz commer-
cial aircraft band. The 800 MHz interference was heard
only on the 2005, not the 2004. Other than that, inter-
modulation interference from paging affected both
scanners to the same degree, and on the same frequencies.
Although both the 2004 and 2005 can suffer the effects of
intermod, they are much more immune than the overly sen-
sitive, image laden Bearcat 800XLT. The PRO-2005 has a
10 dB attenuator, operable by a slide switch on the rear.
- 5 -
The up conversion design of both the ICOM R-7000 and
Radio Shack PRO-2005 allows use of a very high IF (inter-
mediate frequency), which helps avoid image problems.
The PRO-2004 owner's manual contains a frequency alloca-
tion chart and a section on images. This section appears
in the manuals for other Radio Shack models, and was
thoughtlessly thrown into the 2005 manual. It babbles on
about images being 21.4 MHz away from the real frequency
-- true for simpler models, but not so for the PRO-2005.
The audio output quality is good, although the top
mounted speaker directs the sound at the ceiling, but
adding an external speaker would allow the sound to be
directed at the user.
Unfortunately, the audio level of AM signals is somewhat
below that of NBFM signals, requiring a different setting
of the volume control. When scanning both AM and NBFM
modes, one has to find a compromise position of the
volume control.
The PRO-2005 squelch control has a wee bit too much hys-
teresis, a trait inherited from its ancestors. It's like
having too much play in a car's steering wheel, or back-
lash in a gear set. This hysteresis forces one to keep
the squelch at a tighter setting, missing weaker signals
when scanning or searching. It's not as sloppy as in the
early PRO-2004s. I've successfully eliminated this prob-
lem completely by replacing a single resistor on the
800XLT, as well as the PRO-2002, PRO-2003, PRO-2004 and
PRO-24 scanners.
Mechanical Construction
The PRO-2005 is lighter than the 2004. It is enclosed in
a gray plastic cabinet, with a plastic front panel. If
one is going to pay $420, one deserves to own some metal,
but several stages are internally shielded in their own
metal compartments. The entirely plastic cabinet of the
older PRO2003 allowed wideband noise to radiate out of
the scanner and into nearby shortwave receivers.
The PRO-2005 vertical front panel is an advancement over
the sloping panel of the 2004. Now you can stack the
scanner on top of other equipment and see the controls
without standing up. If sitting directly on a table, two
hinged plastic feet, padded with rubber bumpers, can fold
out from under the front of the radio to tilt it at a
good viewing angle.
- 6 -
There is a single BNC antenna connector on the rear of
the PRO-2005, and a single telescoping antenna is sup-
plied.
Internal construction is excellent, and the internal
shielding is commendable. Interstage shielding is very
important in a wide band receiver, to prevent it from
"hearing itself", an undesirable phenomena which results
in birdies. The PRO-2005 owner's manual lists the birdie
frequencies. The shielding is much better in the PRO-
2005 than in the 800XLT, which uses no shielding around
the 800 MHz converter stage, and probably accounts for
some of the birdies in the Bearcat.
Frequencies and other indicators are displayed on a back-
lit LCD (liquid crystal display) panel, and the level of
backlighting can be dimmed by a pushbutton switch.
Vision impaired scanner buffs will appreciate the conven-
tional raised rubber keyboard in the PRO-2005, which
replaced the flat membrane keyboard in the PRO-2004.
Only moderate pressure is required for actuation, and key
depressions are confirmed by a mild "beep" audio tone.
The PRO-2005 is the right size to fit under the dashboard
of intermediate sized cars. Although it can be operated
on 12 VDC, neither a mobile power cord nor mounting
bracket are provided. These items were included with
earlier, pre-PRO-2004 Radio Shack models. The AC power
cord is not detachable, and would have to be bundled up
to keep it out of the way in a mobile installation.
Owner's Manual
The user manual is outstanding compared with the fold out
sheet furnished with Uniden scanner.
A single page frequency allocations chart is included,
but is not current. There is no schematic. Thankfully,
detailed service manuals for Radio Shack scanners are
usually available for $7.50 or $10.00.
The PRO-2005 is warranted for 1 year, which is reassur-
ing.
What's Missing?
So with all these neat features, what's missing from the
PRO-2005? A "search and store" mode, like that on the
- 7 -
ICOM R7000 and older Bearcat 250 would have been nice. A
lighted keyboard and a signal strength meter would also
be welcome, as would a mobile mounting bracket and SCA
output jack.
Summary
If all one wants is a scanner to monitor local police and
fire, there are certainly cheaper and simpler models than
the PRO-2005. This scanner is for those who enjoy
actively exploring voice communications in the VHF/UHF
spectrum. If you already own a PRO-2004 and have added
the diode to expand it to 400 channels, there is little
to be gained by purchasing a new PRO-2005 -- unless, of
course, you are a passionate scanner collector.
The PRO-2005 has the right features and performance,
especially for scanning the wide 225-400 MHz military
aircraft band. Good design should not to be taken for
granted. GRE engineers used the power of the micropro-
cessor to implement useful features in the PRO-2005.
Similar processing horsepower was not used so wisely in
the Yaesu FRG-9600.
At about $420, the PRO-2005 provides a good alternative
to those not wishing to spend $1050 for an ICOM R7000.