BC200XLT, is it any good?
george.w.erhart
I have a wimpy RS PRO-33, 20 channel scanner, and would like to know if
this is a reasonable scanner to move up to. I have priced the PRO-43 and
here in Columbus, it is ~$349.
Does anyone have the specs/features for this scanner handy?
Can it scan a range and save what it finds?
Does it do Celular?
How many channels?
Etc!
Thanks in advance!
--
George Erhart
AT&T Bell Laboratories
Columbus, Ohio
att!cbvox!gwe or g...@cbvox.att.com
Bob Parnass, AJ9S
George Erhart said:
> A local hardware store is advertising a Bearcat BC200XLT for $249.90.
You can buy a 200xlt from National Tower Co, Shawnee Mission, KS,
for $205. Call them at 913-888-8864 or call 800-555-1212 for
their 800 number.
> I have a wimpy RS PRO-33, 20 channel scanner, and would like to know if
> this is a reasonable scanner to move up to. I have priced the PRO-43 and
> here in Columbus, it is ~$349.
You can buy the PRO-43 at discount (under $300) from Marymac Industries,
Katy, Texas. Call them at 800-231-3680.
> Does anyone have the specs/features for this scanner handy?
I assume you mean the PRO-43. I've owned both the PRO-43 and
200xlt and prefer the PRO-43, although not by a large margin... smaller,
more freqency coverage, no images, more flexible battery arrangement,
etc.
> Can it scan a range and save what it finds?
No, not automatically store them.
> Does it do Celular?
Lose one diode in the PRO-43. Crush one resistor in the 200xlt
or hear 'em on their images.
> How many channels?
200
THE RADIO SHACK PRO-43 PORTABLE SCANNER
by Bob Parnass, AJ9S
The new Radio Shack PRO-43 is a small portable scanner made
by General Research Electronics (GRE) which lists for about
$350. Although it is a good step above other Radio Shack
portable scanners, hobbyists awaiting a portable version of
the famous PRO-2006 scanner will be somewhat disappointed.1
For instance, the PRO-43 is an "extended coverage" and not a
continuous coverage scanner, covering these bands:
30 - 50 MHz (5 kHz steps), [30 - 88 MHz after modification]
118 - 136.975 MHz (25 kHz steps)
137 - 174 MHz (5 kHz steps)
220 - 225 MHz (5 kHz steps)
225.0125 - 512 MHz (12.5 kHz steps)
806 - 823.9375 MHz (12.5 kHz steps) [806 - 999.9875 MHz
after modification]
851 - 868.9375 MHz (12.5 kHz steps)
896 - 999.9875 MHz (12.5 kHz steps)
Note the omission of the 10 meter ham band, the cellular
phone band, the 75 MHz band, and the lack of coverage above
1000 MHz. Luckily, the September 1992 issue of Monitoring
Times details a modification to restore cellular phone band
coverage and expand VHF-low band coverage to 30 - 88 MHz.2
While the PRO-2006 has 400 channels, the PRO-43 has only 200
channels divided into 10 banks. Individual lockout and 2
second rescan delay may be selected for each of the memory
channels. Users may select between AM and narrow band FM on
any frequency. The PRO-2006 has 10 pairs of search limits
__________
1. See "The Realistic PRO-2006," by Bob Parnass, AJ9S, in
Monitoring Times, October 1990.
2. Speaking from experience, this modification is
conceptually simple, but is quite a bit more difficult
than restoring coverage in other scanners. It requires
skill and good tools, including a tiny soldering iron.
One must desolder a tiny surface mount diode and
resolder it in a different place observing the proper
polarity.
- 2 -
but the PRO-43 has only one pair and the step sizes are fac-
tory set. The PRO-2006 had selectable step sizes.
Both models have 10 "monitor" memories which can be written
manually during a search.
The HyperscanTM feature means the PRO-43 is supposed to scan
at 25 channels per second and search at 50 steps per second.
The radio scans twice as fast, measured at 50 channels per
second by the reviewer! When enabled, the priority channel
is checked every 2 seconds. As in the PRO-2006, any channel
may be designated as the priority channel.
Physical
The PRO-43 is just the right size for a portable scanner.
It is smaller than the PRO-37 and Uniden 200XLT but larger
than the tiny Icom R1.3 The gray plastic case feels about
the same as a 200XLT, neither as rugged as the Icom IC-2GAT
walkie talkie, nor as thin and chintzy as the PRO-37.
Inside, there are 3 printed circuit boards and most of the
components are of surface mount technology.
The top panel contains volume and squelch knobs, a 1/8" ear-
phone jack, and a BNC antenna connector. A plastic belt
clip of dubious strength is fastened to the rear with 2
screws.
A semirigid rubberized antenna is furnished with the PRO-43.
Performance Issues
The PRO-43 and Uniden 200XLT were tuned to the same frequen-
cies both using their stock rubberized antennas.
On 857.4375 MHz, the PRO-43 heard Joliet Police signals full
quieting which barely broke squelch on the 200XLT, due
partly to the poor 800 MHz performance of the antenna sup-
plied with the 200XLT. When the PRO-43 antenna was placed
on the 200XLT, the 200XLT reception improved noticeably, but
it was still not as good as the PRO-43.
__________
3. See "Uniden/Bearcat 200XLT Scanner Review," by Bob
Parnass, AJ9S, in the RCMA Journal, October 1988.
- 3 -
On 146.94, 162.475, and 460.1 MHz, the PRO-43 and the 200XLT
were close in sensitivity.
When connected to an outdoor AV-801 antenna, paging
interference rendered several VHF high band channels unus-
able. The problem disappeared when using the rubberized
antenna supplied instead.
Owing to the use of up conversion, a high first intermediate
frequency, images don't appear to be a problem as they were
on other Radio Shack portable scanners like the PRO-34 and
PRO-37. The PRO-43 IF frequencies are specified at 608.005
- 611.2 MHz, 48.5 MHz, and 455 kHz.
Somewhat "Mushy" Audio
The PRO-43 uses an LM-386 audio output IC and the radio is
loud enough, but distorts severely when the volume control
is advanced too far. This is partly due to the internal
speaker as there is less distortion when using an external
Motorola lapel speaker plugged into the earphone jack.
The PRO-43 audio lacks high frequency response. By com-
parison, the Uniden 200XLT has cleaner audio and more of it,
especially when using the internal speaker.
Batteries
The PRO-43 requires 6 AA batteries, but none are included.
A battery clip slides up into the bottom of the radio case
and a separate trap door slides over it. Alkaline cells or
NiCd cells will bring the scanner to life. Like most other
Radio Shack portables, there are 2 jacks on the side, but
they are smaller than usual. An optional, AC operated "wall
wart" power supply/charger can power the radio or recharge
NiCd batteries.
Current drain from batteries was measured at 88 ma. while
scanning and 90 - 140 at various settings of the volume con-
trol with the squelch open. The PRO-43 averages 36% higher
current drain than the 200XLT which means the batteries will
need recharging more frequently.
Keyboard and Display
The user manual explains that the KEYLOCK slide switch "dis-
ables the keypad to prevent accidental program changes." In
truth, most of the keys are disabled. The MANUAL and SCAN
- 4 -
keys remain enabled.
The liquid crystal display (LCD) is a smaller version of the
display on the PRO-37. Being smaller, it is somewhat more
difficult to read than the 200XLT display. Pushing the
LIGHT button lights a single lamp behind the display. It
stays lit for only as long as you keep the button pressed
and is not latched or timed as in the 200XLT.
Summary
People who want a portable which covers both civilian and
military aircraft frequencies should check out the PRO-43.
The PRO-43 will be attractive to hobbyists who want more
frequency coverage and fewer images in a smaller package
than the PRO-37 or Uniden 200XLT and who don't want to fight
the problems of using the more feature rich AOR 1000XLT.
x
IMPROVED AUDIO FOR THE PRO-43 SCANNER
by Bob Parnass, AJ9S
The Radio Shack PRO-43 scanner audio is too bassy.1 The
lack of treble makes it difficult to hear the PRO-43 in
noisy situations, especially while listening in a car
or truck. Louis Shirley sent me a schematic and sug-
gested I remove C341, a tiny 0.015 ufd surface mount
capacitor.
I'm glad to report that removing C341 made a great
improvement. The audio is now much "crisper," more
like the Uniden 200xlt, although still not quite as
loud. Turning the volume control up still overloads
the PRO-43's small, internal speaker, but there's less
need to do that once C341 is removed.
The PRO-43 contains 3 printed circuit boards, and the
middle (second) board contains the audio circuitry.
Finding C341 is difficult, as it is neither marked with
a value nor a component designation. It is located on
the foil side of the middle board, under IC304, an
LM386 amplifier IC. C341 is in parallel with, and phy-
sically next to, R350 (33,000 ohm). R350 is slightly
larger than C341 and is marked 333. Both R350 and C341
are connected between pin 2 of the LM386 and ground.
A Note About 50-88 MHz Reception
Now that I have a schematic, I see that the European
version of the PRO-43 has different coils and capaci-
tors in the low (mid) band front end filter. That
explains why the 75 MHz sensitivity isn't stellar after
adding diode D3 to enable 30-88 MHz coverage.
__________
1. See "PRO-43 Product Review," by Bob Parnass, AJ9S, in
the November 1992 RCMA Journal.
UNIDEN/BEARCAT 200XLT
SCANNER REVIEW
by Bob Parnass, AJ9S
For a long time now, radio enthusiasts have awaited the
arrival of a decent portable scanner with 800 MHz coverage.
Users had grown accustomed to the good sensitivity and reli-
able performance found in portable models without 800 MHz,
like the Uniden/Bearcat 100XL, the Azden-manufactured
Regency HX1500, and GRE-manufactured Radio Shack PRO-30.
Unfortunately, early 800 MHz models, like the AOR-
manufactured Regency HX2000 and HX2200 were disappointing.
Now, the wait for a good 800 MHz portable is over, because
the Bearcat 200XLT is here and it's a winner.
Physical
The new Uniden/Bearcat 200XLT is manufactured in Taiwan, and
looks identical to the tall, gray 100XLT.1 The case is
entirely plastic, and the battery and charging circuitry is
contained in a slide on pack. The differences between the
200XLT and the 100XLT are in 800 MHz band coverage and
number of channels (200 vs. 100).
The "real" volume and squelch knobs on top have a positive
feel, and there is little play in the squelch control.
The closely spaced keys on the 200XLT keyboard are made of
soft rubber, and are well labeled. Marshmallow-like keys,
combined with fat fingers, require extra care when entering
frequencies. The lack of a "beep" tone to confirm key
depressions, and the slight amount of tactile feedback,
makes it necessary to watch the display to ensure you pushed
the keys far enough.
__________
1. See "Uniden/Bearcat 100XLT Scanner Review," by Bob
Parnass, AJ9S, in The Radio Enthusiast, March 1988.
- 2 -
Memory Organization
As with the 100XLT, the 200XLT's strong point is the amount
and organization of its memory. The 200 memory channels are
divided into ten banks.
Memory banks and channels may be selected or locked out.
The banks are "hard partitioned," just like Bearcat scanners
of old. By this I mean, Bank 1 includes channels 1-20, Bank
2 channels 21-40, etc. Regency used "soft partitioned"
banks in their HX1500 and TS2 models, but the peculiar
Regency system prevents channels from being locked out dur-
ing a bank scan. Now that Uniden bought out Regency's consu-
mer line, the soft bank concept may die with the current
Regency models.
The large channel banks do have their place, particularly
when scanning 800 MHz trunked systems and cordless phones.
Banks aside, having 200 channels means no longer having to
settle for 10 or 16 most favored frequencies when away from
home. Now you can bring it all with you. My 200XLT banks
are programmed with frequencies for different situations:
- Bank 1: 20 of the most important frequencies for local
sheriff, fire, ham repeater, plant security, etc. I
usually scan this bank unless I'm hunting around for
something else.
- Banks 2, 3, 4: Government frequencies by agency.
- Bank 5 contains VHF-lo and VHF-hi low power and
itinerant business frequencies. Bank 6 contains simi-
larly allocated UHF frequencies. I scan these banks
when I'm at a shopping mall, fair, sporting event, or
anywhere else I see walkie-talkies in use.
- Bank 7: Just the frequencies I want to monitor while in
the office.
- Bank 8: Police, fire, and emergency services for other
communities in this part of the state. There's almost
always something happening on these channels, even in
the wee hours of the morning, when my county is asleep.
The remaining banks leave 40 channels just for trial-and-
error searching!
The 200XLT scans at 15 channels/second, about twice as fast
as Radio Shack's top of the line PRO-32 handheld. When the
200XLT is powered on it always comes up scanning with
- 3 -
priority off.
The LCD display panel contains all the usual indicators, and
can be back lit for 15 seconds with a green light when the
proper button is pressed.
Innovations
Both the 200XLT and 100XLT feature set include new
surprises. The first channel of each active bank is a
priority channel, making 10 priority channels in all. There
are 10 levels of priority. For example, channel 1 priority
takes precedence over priority channel 11, which takes pre-
cedence over priority channel 21, etc. When the priority is
switched on, the 200XLT samples all the unlocked priority
channels (in active banks) every 2 seconds.
I program the first channel of each bank with the most
important frequency for that bank. The priority sampling
does appear to "chop up" signals a little more than on older
models that sample only a single priority channel. When the
power is turned off, then on again, the priority key must be
pressed manually.
Let's see, did I program in that new K-Mart frequency, 154.6
MHz somewhere? Just type 154.6, ENTER when positioned to a
channel you don't care about, and the LCD will display "CH
29", for instance, if you already have 154.6 MHz in channel
29.
Stated a different way, if one tries to type a frequency
into the 200XLT that has already been programmed in another
memory channel, the display will flash the channel number in
which the frequency has already been programmed. One can
override by depressing ENTER again, and the frequency will
be stored in the current channel.
This "query" feature is great - especially in a scanner with
so much memory.
There is a single button to search all VHF NOAA weather
channels, a feature now commonplace on newer UNIDEN
scanners.
Battery Pack
The 200XLT comes with a BP-200 7.2 V Sanyo battery pack
which slides onto the bottom of the radio. There is a
charging jack, marked 12 VDC, and a red charging LED on the
- 4 -
back of the pack. The pack is not supposed to be opened,
but the curious need only remove 2 screws. Inside, are the
charging components (regulator circuit), and 6 AA size Sanyo
cells wrapped in yellow heat shrunk plastic.
The BP-200 battery pack has a 600 mAH capacity, whereas the
BP-205 (supplied with my 100XLT) contained batteries inter-
nally marked 550 mAH.
When you buy the 200XLT, the 16 hour wall power supply is
furnished, and is marked 12 VDC 500 mA. The wall unit is
not a charger - the regulator/charging circuit is actually
inside the battery pack and uses the 12 VDC furnished by the
wall power supply for charging the NiCds at 60 mA. Since
the 200XLT draws about 60 mA while scanning (while fully
squelched), the batteries will not be charging if the
scanner is on while the power supply is connected. To depo-
sit a net charge into the batteries, the radio must be
turned off.
The radio can be used with the wall power supply when the
batteries are dead, but unlike older crystal controlled
portables, there is no easy way to power the scanner exter-
nally, while effectively charging the internal battery.
Neither is there a way to fast charge the supplied NiCd
pack, and the manual cautions against leaving the supplied
power pack plugged in for long periods of time (I assume
Uniden means with the scanner OFF).
A PS-001 mobile power cord is available for $4 from UNIDEN,
as is a spare antenna.
The owner's guide says to expect "up to 5 hours of depend-
able use" between charges. Now 5 hours isn't enough for
many scanner buffs, but perhaps UNIDEN's idea is to stimu-
late demand for extra BP-200 slide-on battery packs. My
200XLT was used for about 7 to 8 hours before the battery
indicator began to flash, but Dan Doyle reports he gets only
5 hours between charges. It is the audio amplifier stage
that draws the most current, so battery life is dependent
upon channel activity, and the volume control setting.
Using an earphone, which draws less current than a speaker,
can mean longer battery life.
Great Audio
The audio output is rated at 480 milliwatts. As with the
100XLT, the 200XLT audio sounds great! There is plenty of
undistorted audio available from the front speaker, making a
Radio Shack PRO-30 sound like a whisper.
- 5 -
Inside Construction
The internal construction of the 200XLT is clean, but
thoughts of home repair vanish as soon as one opens the
200XLT case. Tiny surface mount components abound. You
won't find these parts at Radio Shack, and you wouldn't want
to solder them in anyway.
The 2 main circuit boards are surrounded by an internal
metal frame, and the IF and 800 MHz front end circuits are
on small circuit boards, mounted vertically on the main
audio/RF board. The PLL is on another small board.
How Does It Work?
My first 200XLT had a problem. The squelch threshold was
different for different bands, and had too much hysteresis,
which caused it to skip over VHF signals and stop only on
UHF signals. This is probably caused by misalignment,
rather than a design flaw, as four friends with 200XLTs had
no such problems. Grove Enterprises graciously swapped the
defective radio for another brand new 200XLT, and the
exchange took about a week using UPS shipping.
The squelch action on the new 200XLT is quite good, much
better than on the 760XLT and PRO-2004, both of which have
too much hysteresis. UHF sensitivity is excellent, and
while I don't often listen to aircraft, the sensitivity in
the AM aircraft band appears adequate.
Using an outside antenna, the 200XLT is sometimes bothered
by the obnoxious 300 watt paging transmitter nearby, but so
was my 800XLT on an indoor whip. Expecting a portable
scanner to behave well on an outside antenna may be asking
too much.
Most every superheterodyne receiver has birdies, those
places on the dial where the receiver "hears itself." The
200XLT owner's guide does not list birdies, but they're
there. Many of the birdies are weak, and disappear when the
heliflex antenna is replaced with an outdoor antenna.
The first IF is 10.85 MHz, and the second IF is 450 KHz.
Images of stations in the UHF range were noted 21.7 MHz
higher than their assigned frequencies. The cellular tele-
phone bands are disabled, but strong cellular phone signals
are heard 21.7 MHz higher than their assigned frequencies
anyway. Some people might consider this an advantage!
Besides, there's not much activity above 892 MHz to listen
to yet.
- 6 -
The 200XLT hears TV stations where they shouldn't be - in
the 850 and 890 MHz bands - thanks to multiple injection
into the mixer stage, no doubt.
Scanners sold by Grove Enterprises are supplied with
instructions detailing how to restore cellular phone band
coverage. The instructions for the 200XLT just involve
crushing one resistor, but I haven't tried this.
Both my 200XLTs were a few kHz off frequency in the 800 MHz
band. Weak signals were slightly distorted, and using the
search feature revealed an asymmetry - I could hear the sta-
tion +12.5 kHz stronger than -12.5 kHz away from what was
supposed to be the center frequency.
Having no schematic, I deduced that the orange non-ceramic
trimmer capacitor on the PLL board (the board with the hor-
izontal crystal on top of the IC) determined the PLL refer-
ence frequency. I programmed a frequency near 850 MHz on
the 200XLT, then adjusted the trimmer capacitor while
listening to the local oscillator signal 10.85 MHz lower on
my ICOM R-7000. The discriminator meter on the R-7000 makes
that radio a great test instrument, but be sure your R-7000
is properly aligned before using it to align other radios!
What You Get
Like the 100XLT, the 200XLT comes with a leather-like case,
but it's gray instead of black. The case has openings in
all the right places, so one can charge the battery without
removing the radio from the case. There is a belt loop sewn
on the back, but a user must unfasten his/her belt to thread
it through the loop, a big inconvenience. The scanner can-
not be left standing up while in the case, because the case
bottom is rounded.
There is no belt clip on the 200XLT. To carry the scanner
on my belt, I use a yuppie-ish Bianchi, hand-tooled leather
case, made for the old Kenwood TR2400. My wife bought the
used case at a hamfest for $1.50.
The 200XLT also comes with an AC wall adapter, an earphone,
and a helical antenna blessed with a BNC connector.
UNIDEN scanners no longer come with an owner's manual, but
with a difficult to use fold out sheet instead. The
instructions aren't great, but will tell you most of what
you need to know. Of course, you don't get a schematic, but
you can order it.2
- 7 -
Summing Up
The UNIDEN 200XLT works well. It scans fast, sounds good,
and excels in the amount and organization of its memory
channels. The 800 MHz coverage, multiple priority, fre-
quency finding, and slide-on battery pack features make it
the "Lincoln Town Car" of portable scanners.
So far, the 200XLT is the best handheld scanner I've ever
used. Now I'm waiting for Radio Shack to shrink the PRO-
2004, so we can enjoy continuous frequency coverage in a
portable scanner!
BATTERY CONSUMPTION OF THE
UNIDEN/BEARCAT 200XLT SCANNER
by Bob Parnass, AJ9S
The Uniden/Bearcat 100XLT and 200XLT scanners are the first
portable scanners with enclosed, slide on battery packs.
Some 200XLT owners don't get the battery life they expect.
They report having to recharge the slide on NiCd (Nickel
Cadmium) battery pack after as few as only 3-1/2 hours of
operation. Owners expect the battery pack to last longer,
at least the 5 hours mentioned in the documentation supplied
with the radio.
Much has been written about NiCd battery characteristics and
charging in general. This article will not rehash general
NiCd charging techniques. Rather, we will analyze the
current consumption of the Uniden/Bearcat 200XLT scanner,
and make recommendations specific to that radio.
BP-200 Battery Pack
The BP-200 battery case contains six Sanyo 600 mAh NiCd
cells soldered in series configuration and wrapped in heat
shrunk plastic. This pack furnishes 7.2 VDC to the radio.
A charging regulator circuit and a light emitting diode are
also contained within the battery case.
__________
2. UNIDEN, Parts Department, P.O. Box 50822, Indianapolis,
IN 46250.
- 8 -
In contrast to the Yaesu FT-23R 2 meter walkie-talkie, which
is supplied with a wall-mounted charger, the 200XLT wall-
mount unit is actually a 12 VDC power supply. Since the
BP-200 regulator circuitry is contained within the battery
case, 200XLT owners cannot easily opt for rapid or trickle
chargers.
Measurements and Their Implications
The 200XLT's current drain was measured under several condi-
tions, and a graph appears later in this paper. Tests show
that the 200XLT consumes more current on higher bands than
it does on lower bands. For instance, listening on the 870
MHz band takes 13 mA more current compared with the vhf-lo
band.
Measurements indicate that 200XLT current consumption is
independent of scanning, searching, or manual modes, pro-
vided the scanning or searching is within the same band.
This implies:
o If you must monitor 870 MHz frequencies for a prolonged
period, it is more "battery-wise" to scan a mixture of
870 MHz and low band channels.
Several factors can contribute to "shortened" battery life.
Shortened recharge intervals will be needed if using the
radio with the volume control at a loud setting. In port-
able receivers, the audio amplifier stage generally consumes
more current than any other stage. The 200XLT has a more
powerful, cleaner audio output stage than do other portable
scanners.
The factory supplied earphone is inconvenient and uncomfort-
able, but test results prove:
o Using the earphone decreases current consumption.
Using an earphone saves about 14 mA indoors, and about 50 mA
in noisy situations where one might have the volume control
set at maximum.
When using an earphone with the test radio, the best volume
control setting was at the 10 o'clock position, versus 12
o'clock when using the internal speaker.
Listening to "busy" channels generally consumes more current
than listening to infrequently used channels. One surpris-
ing exception, borne out by test results, is that:
- 9 -
o When using an earphone (at 10 o'clock volume setting),
listening to busy channels actually consumes less
current than when the 200XLT is fully squelched!
Improper battery charging can require the battery be charged
more often than normal. If the battery indicator on the
200XLT's panel flashes, charge the battery pack for a full
16 hours. Test results showed:
o The low battery indicator flashes when battery voltage
falls to 7.2 volts or less.
The 200 memory channels in the 200XLT are backed up by a
capacitor kept charged by the NiCd battery pack. Current is
required to retain the memory information, even when the
radio is turned off.
How much battery drain is due to maintaining the memory
information? To answer this question, the author measured
the current required to backup the memory in the 200XLT. A
Fluke 8024B digital multimeter indicated that:
o The 200XLT draws about 0.50 mA with the power switched
off.
The six cell Sanyo NiCd pack is rated for 600 mAh capacity.
If the batteries were perfect, and had infinite shelf life,
the memory backup would drain a fully charged battery flat
in 50 days:
600 mAh / 0.50 mA = 1200 hours
= 50 days
But no NiCd battery is perfect -- all have a finite shelf
life. NiCd batteries will discharge by themselves, through
spontaneous chemical decomposition, even when not connected
to a load. The General Electric Company indicates that the
average NiCd will lose about 1% of its capacity per day at
70 degrees F.
The author developed a discrete time computer simulation
which shows that:
o The cumulative effects of self discharge, combined with
0.50 mA drain due to memory backup, will deplete a
fully charged 200XLT battery pack in about 40 days.
A plot of the predicted daily decrease in battery capacity
appears elsewhere in this article. The plot indicates that:
- 10 -
o To get the most use between recharges, charge your
200XLT right before using it. If you charge your 200XLT
battery, but then leave it in a drawer for a week, you
will have already lost 20% of the operating time before
the next recharge is required.
Average self discharge at 100 degrees is about double (2%
per day) the discharge at 70 degrees, which is a good reason
to avoid storing NiCd batteries in a warm automobile. At
100 degrees, it only takes about 34 days to deplete the
200XLT battery.
These Recommendations Can
Work For You
By using his 200XLT right after charging its battery for 16
hours, Mr. Ron Smithberg reported he is now getting 6-1/2
hours use on a charge instead of the 3-1/2 hours he got pre-
viously.
References
1. Parnass, Bob, AJ9S, "Uniden/Bearcat 200XLT Scanner
Review," RCMA Newsletter. October 1988.
2. Nickel-Cadmium Battery Application Engineering Hand-
book, Second Edition, General Electric Company, Bat-
tery Business Department. P.O. Box 861, Gainesville,
FL 32602. Copyright 1975. pp 7-14, 7-15.
For further information on NiCd batteries, see:
- The ARRL Handbook for the Radio Amateur, 65th Edition.
The American Radio Relay League, Newington, CT. Copy-
right 1988. ISBN 0-87259-065-8. pp 6-25, 6-26, 6-27,
6-28.
- Meyer, Budd, K2PMA, "Charge It! Your NiCad, That Is,"
QST, March 1977. pp 29-31.
- Meyer, Budd, K2PMA, "Nickel-Cadmium Pandemonium," QST,
March 1982. pp 32-34.
- 11 -
______________________________________________________
| Additional Current Consumed by Uniden/Bearcat 200XLT|
| Per Band Over VHF-lo Band |
| |
| Band Additional Current (mA)|
|_____________________________________________________|
| VHF-hi 1 |
| UHF 5 |
| 870 13 |
|_____________________________________________________|
_________________________________________________________________________
| Uniden/Bearcat 200XLT Scanner Current Consumption |
| Measured Under Various Operating Conditions |
| |
| Condition Measured Current Consumption (mA) |
|____________________________|___________________________________________|
| sqlch closed vhf-lo | 49 *************** |
| sqlch closed vhf-hi | 50 *************** |
| sqlch closed uhf | 54 **************** |
| sqlch closed 870 | 62 ******************* |
| | |
| sqlch open 10oclock vhf-lo | 48 *************** |
| sqlch open 10oclock vhf-hi | 49 *************** |
| sqlch open 10oclock uhf | 53 **************** |
| sqlch open 10oclock 870 | 61 ******************* |
| | |
| sqlch open 11oclock vhf-lo | 57 ***************** |
| sqlch open 11oclock vhf-hi | 58 ****************** |
| sqlch open 11oclock uhf | 61 ******************* |
| sqlch open 11oclock 870 | 69 ********************* |
| | |
| sqlch open 12oclock vhf-lo | 64 ******************** |
| sqlch open 12oclock vhf-hi | 65 ******************** |
| sqlch open 12oclock uhf | 68 ********************* |
| sqlch open 12oclock 870 | 76 *********************** |
| | |
| sqlch open full vol vhf-lo | 99 ****************************** |
| sqlch open full vol vhf-hi | 100 ******************************* |
| sqlch open full vol vhf-uhf| 104 ******************************** |
| sqlch open full vol vhf-870| 112 ***********************************|
|____________________________|___________________________________________|
- 12 -
_________________________________________________________
| Predicted Shelf Life of Uniden/Bearcat BP-200 Battery |
| Battery Pack While Connected to 200XLT Scanner |
| |
| Day % of Original Capacity Remaining At End of Day|
|_______|________________________________________________|
| 1 | 97% ***********************************|
| 2 | 94% ********************************* |
| 3 | 91% ******************************** |
| 4 | 88% ******************************* |
| 5 | 85% ****************************** |
| 6 | 83% ***************************** |
| 7 | 80% **************************** |
| 8 | 77% *************************** |
| 9 | 74% ************************** |
| 10 | 72% ************************* |
| 11 | 69% ************************ |
| 12 | 66% *********************** |
| 13 | 64% *********************** |
| 14 | 61% ********************** |
| 15 | 58% ******************** |
| 16 | 56% ******************** |
| 17 | 53% ******************* |
| 18 | 51% ****************** |
| 19 | 48% ***************** |
| 20 | 46% **************** |
| 21 | 43% *************** |
| 22 | 41% ************** |
| 23 | 38% ************* |
| 24 | 36% ************ |
| 25 | 34% ************ |
| 26 | 31% *********** |
| 27 | 29% ********** |
| 28 | 27% ********* |
| 29 | 25% ********* |
| 30 | 22% ******* |
| 31 | 20% ******* |
| 32 | 18% ****** |
| 33 | 16% ***** |
| 34 | 14% ***** |
| 35 | 12% **** |
| 36 | 10% *** |
| 37 | 7% ** |
| 38 | 5% * |
| 39 | 3% * |
| 40 | 1% |
|_______|________________________________________________|
Computer model based on these assumptions:
- 13 -
1. A new battery, fully charged to 600 milliampere-hour
capacity at start of day 1.
2. Continuous drain of 0.50 mA to retain 200XLT memory.
3. Ambient temperature 70 degrees F.
--
==============================================================================
Copyright 1993, Bob Parnass, AJ9S
AT&T Bell Laboratories - par...@ihlpm.att.com - (708)979-5414