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PRODUCT REVIEW
The Yupiteru MVT-7100
Continuous-coverage handheld scanning receiver with SSB
by
Howard Bornstein
Copyright 4/11/93
Overview
The MVT-7100 is the latest offering in continuous-coverage
handheld scanners by Yupiteru, coming on the heels of its
very successful and well-received MVT-5000 and MVT-7000
scanning receivers. The 7100 adds substantial increase in
capability over the 7000, primarily by dramatically
increasing the number of scan channels, expanding the
overall frequency coverage, and including sideband
reception.
The MVT-7100 is a small, lightweight scanning receiver,
offering continuous coverage from 100 KHz to 1.65 GHz! It
will receive AM, FM, WFM (wide-FM), USB (upper sideband),
LSB (lower sideband), and CW (continuous wave; i.e. Morse
code) transmissions.
The 7100 has 1,000 scan channels organized in ten banks of
100 channels each and one additional dedicated channel for
priority. It offers ten individual search banks with the
ability to lock out up to 500 frequencies during a search.
It can search in the following steps:
FM:
1 KHz, 5 KHz, 6.25 KHz, 9 KHz, 10 KHz, 12.5 KHz, 20 KHz, 25
KHz, 50 KHz and 100 KHz.
Wide FM:
50 KHz, 100 KHz
AM:
1 KHz, 5 KHz, 6.25 KHz, 9 KHz, 10 KHz, 12.5 KHz, 20 KHz, 25
KHz, 50 KHz and 100 KHz.
USB/LSB:
50 Hz, 100 Hz, 1 KHz, 5 KHz, 6.25 KHz, 9 KHz, 10 KHz, 12.5
KHz, 20 KHz, 25 KHz, 50 KHz and 100 KHz.
The MVT-7100 is approximately 6.5 inches high, 2.5 inches
wide, and 1.5 inches deep, minus the antenna and belt clip.
It is just slightly taller than the Radio Shack PRO-43,
otherwise it is about the same size. The 7100 is a real
lightweight, weighing in at only 11.5 ounces, without the
antenna, but with the batteries and belt clip.
Accessories
The MVT-7100 comes with an AC adaptor, a set of four nicad
batteries (Hitachi 600 mAh), a car cigarette lighter
adaptor, a belt clip, a wrist strap, an earphone, and a
telescoping antenna with a pivot BNC mount.
Controls
The MVT-7100 is very cleanly laid-out. The top of the unit
contains a BNC connector for the antenna, a knob for On/Off
and volume, a knob for squelch control, and a tuning knob,
which is used for a variety of functions.
On the left side of the unit are three recessed buttons: a
momentary light button, a monitor button, and a keylock
switch. There is also a small hole which contains a reset
switch.
The Light button illuminates both the display and the
keyboard with a very nice greenish light. Alas, it only
stays on while you hold down the button. When will scanner
manufacturers design their products with a method of letting
the user keep the light on, especially when plugged into a
power source?
The Monitor button immediately opens the squelch fully,
allowing you to stop on a weak signal, without worrying
about the scanner resuming its search or scan.
The Keylock performs the usual keyboard lockout of
functions. It locks everything except the volume and squelch
controls and the light and monitor buttons.
On the right side of the unit, you'll find a small hook
which is where you attach the wrist strap. Both the earphone
jack and the power plug are also on the right side of the
unit.
The belt clip attaches on the back and the battery
compartment opens from the back.
The MVT-7100 has a 15db attenuator feature built-in, but you
select it with a keyboard combination, rather than with a
separate button.
The Keyboard
The keyboard is arranged in a 5 X 5 matrix. The keys are as
follows:
1 2 3 SRCH
ATT DELAY SKIP PRI
4 5 6 SCAN
SAVE BEEP PGM MW
7 8 9 STEP
M>VFO M-SCAN P-SCAN MODE
^ 0 . MR
MHz SPR BW
v C/AC ENT FUNC
PASS
The top label of each row is on the key itself and the
bottom label is below the key. You get the top function by
pressing the key and the bottom function by first pressing
the FUNC button and then they key. The ^ and v symbols
represent up and down arrows. The arrow buttons, along with
the tuning knob, are used for stepping through memory and
selecting mode and step increments.
The keys are relatively large size for a scanner this small
and are very easy to press. When the beep feature is turned
on, the scanner gives a variety of audio feedback when you
press a key. This sound can be turned off, if desired.
The Display
The MVT-7100 uses a large LCD display to show the channel
number, the frequency, and various annunciators. The
channel and frequency digits are very large and easy to see.
There is a second level of annunciator, like the mode types
(AM, FM, etc.) which are smaller but still easy to discern.
The third level of annunciators, however, are down-right
microscopic and are just about impossible to make out,
except in strong sunlight. You will primarily learn to
identify these annunciators by their positions, rather than
by the actual text.
The display also shows a 9-segment signal strength meter
across the bottom, which is a very useful addition.
The MVT-7100 was obviously designed to be held in the hand,
nearly parallel with the floor, so that the display is
viewed from below. The contrast is best when viewed from
this angle. When viewed straight on, the display is marginal
and when viewed from even slightly above eye-level, the
display is virtually unreadable. Apparently the designers
didn't think many people would sit the scanner on end and
look at the display directly. In addition, the plastic
covering over the display is highly reflective and picks up
glare easily.
In general, the display won't give you too many problems,
but it could have been better. There is no contrast control
for the display like there is on the MVT-7000.
Operations
In terms of operations the MVT-7100 is much easier to learn
and use than the AOR AR1000/AR1500 but not nearly as easy as
the PRO-43. This is probably because Yupiteru hasn't
licensed the Uniden patents for scanner operation.
The scanner contains ten banks of 100 channels each,
addressed by channel number. It uses a fairly wacky
numbering scheme, however. Bank 1 contains channels 000
through 099, bank 2 contains 100 to 199, etc. bank 0
contains 900 to 999. In other words, in bank 2, for example,
you will never find a channel that starts with a 2! This may
be a bit confusing, especially if you've used other scanners
that number their channels a bit more normally.
The Yupiteru uses a VFO (variable frequency oscillator) mode
to hold "temporary" frequency information. You enter a
frequency into the VFO, select its mode, and step increment,
and then store it into a scan channel. You can't operate on
a value in a scan channel directly. You must first move it
into the VFO, modify it there, and then write it back into
the scan channel. The keys to perform these operations are:
nnn MR (nnn is the channel number. MR reads the frequency
into the VFO).
FUNC MODE (to change the mode).
Choose a mode with the arrows or tuning knob.
STEP (to change the step value).
Chosse a step value with the arrows or tuning knob.
FUNC MW (to write the value back into the same channel).
Once you write a value to a scan channel, the scanner
automatically steps to the next channel which makes
sequential entry of frequencies extremely convenient.
It might seem unusual to have to indicate a step value when
simply storing a frequency into a scan channel. This is due
to the interaction of the tuning knob/arrow keys with the
VFO. They let you change the current frequency up or down,
based on the step value. An unfortunate side effect of the
step value is that it rounds off a frequency so that it
conforms to the current step value.
For example, if you enter 488.3375 MHz into the VFO, but the
step value is 10 KHz, the frequency will automatically be
converted to 488.3300. In order to enter in 488.3375, you
need to use a step of either 12.5 or 6.25 KHz. This isn't as
bad as it may seem, however, because, once you do enter in
the proper step, you can simply dial in the frequency you
want. The display jumps by the step value when you use the
tuning knob or the arrow keys.
It turns out that for most frequency entry, this capability,
along with the automatic advance to the next sequential scan
bank, makes the MVT-7100 one of the easiest scanners around
for entering frequencies--something you will appreciate when
you try to fill up all 1,000 scan channels.
Scanning
Scanning on the MVT-7100 is a little unusual. If you just
hit the SCAN button, the unit starts scanning the entire
1,000 channels sequentially. In order to scan a specific
bank, you must first press the bank number and then the scan
button. For example, to scan bank 5, you would press 5 SCAN.
This is not so strange, except that the unit doesn't
remember which bank or banks you were scanning if you do
anything to stop the scan. You have to press the bank
number(s) each time or the scanner will try to scan the
entire 1,000 channels, which is basically useless.
You may specify up to four banks to be scanned this way by
entering in their numbers before pressing the SCAN button.
For example, to scan banks 3, 5, and 9, you would press 359
SCAN. While it seems strange to limit the number of banks to
four, in practice this is not much of a problem, since you
will rarely want to scan more than 400 channels at one time.
The arrangement of the memory as a 10 by 100 channel matrix
is awkward because your smallest "chuck" of memory is 100
channels. However, the MVT-7100 has some additional features
that allow you to better divide how you use these 1,000
channels.
First, you may lock out (it's called "Pass" in the MVT-7100)
any channel in the scanner so that it isn't included in a
bank scan. This works the way it does in most scanners,
although there isn't a separate display indicator for
lockout. Instead, the CH (channel) annunciator blinks on a
channel that has been locked out.
The MVT-7100 has three different scan methods. The first is
normal scan, which is as described above. You specify a bank
and it scans all unlocked channels in that bank. You may
also set up a programmed scan. You may specify up to ten
channels per bank as "programmed" channels. When you do a
programmed scan of a bank, only the programmed channels are
scanned. This means that you can have a separate sub-group
of ten channels per bank that are scanned independently.
You perform a program scan like this:
nnnn FUNC P-SCAN (nnnn represents 1 to 4 bank numbers).
If you designate a channel as a programmed channel, it will
be scanned in a program scan, even if the channel is locked
out.
You may also specify a mode scan for up to four banks (or
all ten banks if you don't specify any bank number). This
will scan only the channels that are in the same mode as the
VFO. You perform a mode scan like this:
nnnn FUNC M-SCAN (nnnn represents 1 to 4 bank numbers).
These various scan options let you break the 100 channel
bank into more useful sub-groups. For example, let's say
that you put all 40 CB channels into the first 40 channels
in bank 5 (401-440). CB is in AM mode. You then program your
local PD into channels 450-470. They are in FM mode.
Finally, you put in some railroad frequencies into channels
480-490. They are also in FM mode, but you mark them as
"programmed" channels and also lock them out.
With this arrangement you can scan three independent groups,
all in bank 5.
To scan the CB channel, set the VFO to AM mode and perform a
mode scan:
5 FUNC M-SCAN
To scan the PD channels, set the VFO to FM mode and perform
a mode scan:
5 FUNC M-SCAN
(the railroad FM frequencies won't be included because they
are locked out).
To scan the railroad frequencies, perform a programmed scan:
5 FUNC P-SCAN
While you probably wouldn't organize a bank like this, you
get the picture.
One of the unusual aspects of the MVT-7100 is that you can't
lock out scan banks. All the banks are always included in a
scan unless you indicate the specific banks (up to 4) you
want to scan. This is the way you will almost always perform
a scan.
Searching
The MVT-7100 has ten separate search banks. Each search bank
holds an upper and lower limit, a step increment, and a
reception mode. You can change the step and the mode any
time after setting up the search bank, but you can't change
the upper or lower limit without reprogramming the whole
bank. You may also turn the attenuator on for the entire
search bank.
Unlike scan banks, you may not link together several search
banks.
A very useful feature in the MVT-7100 is the ability to lock
out specific frequencies during a search. If you constantly
stop on a open carrier, a data control channel, or just a
noisy frequency, being able to lock out that frequency makes
using the search features dramatically more useful, not to
mention more enjoyable. You may also review the locked out
frequencies and unlock them, if you wish.
Other Features
Skip
The MVT-7100 has a skip feature which is very much like the
Seek feature found on some modern car radios. It can be used
during either a search or a scan and will stop on an active
frequency for 5 seconds and then continue on, even if there
is still activity on the frequency.
Priority
The MVT-7100 dedicates a special channel (channel 1000) as
the priority channel. This channel is checked every 5
seconds when the priority feature is turned on and switches
to it if there is activity on it. Five seconds is really too
long a wait for a priority check and you may miss short
replies or the beginnings of communications due to this
excessive wait. More typical priority delays are about 2
seconds.
Delay
The MVT-7100 has a delay feature but it is a bit confusing.
The purpose of the delay is to wait a fixed time after a
transmission ends before resuming the scan or search,
because there may be a response and you will probably want
to hear it. On the 7100, when the delay is off, the unit
waits two seconds before resuming. When the delay is on, it
waits four seconds! Again, this is probably due to the fact
that Uniden holds the patents for variable timed delays on
scanners and Yupiteru hasn't licensed them.
What this means is that you can never remove the delay
entirely, which may make it a bit difficult to scan certain
"trunked" systems. In these cases, the response may be on a
different frequency than the original transmission, and if
you wait around with the delay, you may miss it.
Save mode
The MVT-7100 has three special battery-saving modes that put
the scanner to sleep for brief moments and then wake it up
to check for channel activity. This save mode only works
when you are in memory or VFO mode. It doesn't work when you
are scanning or searching.
This mode can conserve your batteries if you are sitting on
one station. You have to explicitly put the unit into save
mode each time, and the mode is canceled when you search or
scan. It also makes a quiet, but noticeable, popping sound
during its save mode.
Attenuation
You may specify a 15db attenuation of the signal on a
channel by channel basis. Using the key sequence FUNC ATT,
you specify whether a channel has attenuation or not. You
may also turn on the attenuator during a search. In this
case, the attenuation will apply to all frequencies
encountered in the search.
Sound quality
The MVT-7100 has a 100 mW amp that gives good quality sound
through the internal speaker. The speaker can be driven at
full volume without distortion. The sound quality is a
little on the bassy side. While adequate in volume for
normal applications, you may need additional amplification
when using the 7100 in the car.
Performance
The MVT-7100 is a real champ when it comes to performance.
It is fast, sensitive, and relatively easy to operate. More
detailed descriptions of its performance characteristics
follow.
Speed
The 7100 scans and searches at approximately 30 channels per
second. However, the "relative" speed during a search may be
reduced considerably if you can't use the proper search
increment. For example, if you want to search through the CB
channels, you will find that they are spaced 10 KHz apart.
However, they are on 5 KHz boundries; e.g. 26.965 MHz,
26.975 MHz, etc. This means that you have to set the step
value at 5 KHz or you won't be able to actually enter in the
frequency. You search twice as many frequencies as you have
to at 5 KHz, effectively halving the search speed. Some
increments useful in the U.S. (15 KHz and 30 KHz) are
missing.
Sensitivity
The MVT-7100 is an extremely sensitive scanner, comparable
to, if not better than, the very sensitive PRO-43. The
user's manual gives these sensitivity figures (levels in uV
at SINAD 12 db -- lower is better):
Frequency Range AM FM WFM USB/LSB
0.53 MHz - 2 MHz 10.0
2.0 MHz - 30 MHz 1.0 1.5 1.0
30.0 MHz - 1000 MHz .5 .5 .75 .5
1000.0 MHz - 1300 MHz 1.0
These are fairly conservative figures and don't accurately
reflect the real sensitivity of the unit. A review,
performed by Scanners International in April 1993, gave
these laboratory test results (levels in uV at SINAD 12 db):
Frequency AM FM WFM SSB
500 KHz 3.94 2.33 - 5.13
1 MHz 1.27 .76 - 1.45
2 MHz .58 .35 - .75
4 MHz .40 .23 - .38
6 MHz .32 .17 - .27
10 MHz .26 .16 - .23
20 MHz .22 .13 - .16
30 MHz .22 .12 .36 .14
60 MHz .22 .13 .39 .14
100 MHz .21 .12 .38 .13
145 MHz .25 .16 .48 .18
250 MHz .29 .17 .73 .21
435 MHz .35 .22 .67 .26
700 MHz .46 .21 .77 .38
935 MHz .37 .21 .55 .33
1300 MHz - .47 1.73 -
1500 MHz - .52 2.08 -
1650 MHz - 1.31 4.71 -
Intermod
The 7100, like any sensitive, wide-range receiver, is
subject to intermod at various places across the radio
spectrum. Users have reported interference from pager
signals and FM broadcast stations at various frequencies.
Depending on where you live, you may find this more or less
of a problem, especially if certain highly used bands are
wiped out.
Images
The MVT-7100 is triple converted and has very few problems
with images.
RFI sensitivity
The unit could be better shielded than it is. It definitely
picks up radio frequency interference from computers and
will lock up at a variety of different frequencies. You may
need to be as far away as 20 feet from a computer to avoid
this problem. You may also notice sensitivity to RFI while
operating the computer in a car.
SSB operations
One of the special capabilities of the MVT-7100 is the
ability to decode single sideband transmissions. Rather than
requiring the use of a beat frequency oscillator (BFO), the
7100 uses true carrier injection to provide SSB reception.
However, there are still a couple of things to consider. SSB
signals are designed to be tuned 1.4 KHz above and below the
carrier in the MVT-7100. So, instead of just dialing in a
frequency, setting the mode to USB, and getting the station,
you need to tune above the desired frequency by some amount.
While 1.4 KHz is the factory spec, each unit tends to be off
by a certain amount. In addition, the accuracy may change as
the unit warms up. However, once you "zero-in" your own
receiver by watching how far off it appears, you will be
able to accurately dial in the sideband frequencies you are
interested in.
When you are in sideband mode, you get two additional tuning
increments: 50 Hz and 100 Hz. These very fine tuning steps
make it extremely easy to tune in a station accurately.
As an extra benefit, some users have reported that by
listening to speech inversion voice encryption in a sideband
mode, they have been able to understand the transmissions!
Power
The MVT-7100 operates on 4.8 VDC via 4 AA batteries. It
comes with nicads, however, you may also operate it with
alkaline cells. Battery life is between 5 and 6 hours of
operation on a full nicad charge. The unit also comes with
an external 12 VDC adaptor. The adaptor is a 200 mA, 100VAC
adaptor, which is not really adequate for operating the
scanner in America. If you operate the scanner with this
adaptor, the unit will tend to heat up quite a bit. It is
fine for charging the batteries while turned off.
Manual
The manual you get depends on where you obtain the scanner.
Yupiteru provides an English translation of the Japanese
manual, and it is, as expected, a bit hard to understand.
Javiation has rewritten this manual in real English and it
clearly describes all the operations of the MVT-7100. It is
completely sufficient to get you started, although it
doesn't go into detail about things like how organize your
memory channels.
Modifications
There are no known modifications to this scanner, although
it has only been available a short time. Unfortunately, when
you open the unit, you automatically lose all of your
programmed scan channels. This is somewhat of a disincentive
to people experimenting with modifications or adding RFI
shielding to the unit.
Recommendations
This is one of the most powerful, capable, and usable
handheld wide-range scanning receivers ever built. The only
other scanner with its features is the AOR AR1500 and the
MVT-7100 stands heads and shoulders above it in terms of
ease of use, sensitivity, and features. In one handheld
unit, you have the capability of receiving virtually every
type of voice transmission essentially across the entire
radio spectrum! It is quite unbelievable. This unit is
highly recommended!
Where to get it
The MVT-7100 has not (at the time of this review) received
FCC type acceptance in the United States. It may or may not
receive this acceptance before the deadline of April 26,
1993, which will preclude the importation of cellular-
capable scanners. This means that there are currently no
(and may never be) US importers of this scanner. However, a
company in the UK, Javiation, has been able to ship units to
individuals in the US, as long as they are not for resale.
Jonathan Clough, owner of Javiation, has been available on
CompuServe, particularly in HamNet, to take orders and
support users. His support has been superb and he has been
extremely helpful in answering questions, expediting orders,
and keeping his customers appraised of changing
circumstances. By the way, I have no personal interest in
Javiation, except as a satisfied customer.
The price of the MVT-7100 will vary depending upon the
relative strengths of the US dollar, the English pound, and
the Japanese yen. However, it will probably fall in the
range of $550 to $600 US. Price includes shipping by
Federal Express. Jonathan is offering a one year
warranty on units purchased through him.
He may be reached at:
Javiation
Carlton Works, Carlton Street
BRADFORD
West Yorkshire, BD7 1DA
United Kingdom
Phone 0274 732146 (From U.S. 011 44 274 732146)
Fax 0274 722627 (From U.S. 011 44 274 722627)
CompuServe address: 100117,535.
(Internet: 100117.535@CompuServe.COM)
Please send any comments, corrections, or updates on this
review to Howard Bornstein, 76174,637. (Internet:
76174.637@CompuServe.COM)
YUPITERU MVT-7100 wideband handheld receiver Rev. Apr 15, '93
============================================
This is a compilation of comments re:specs on the CompuServe HAMNET forum,
followed by my own comments after using this remarkable radio for a while
Specifications:
Frequency coverage: 530KHz to 1650MHz continuous
Modes: AM, NFM, WFM, LSB & USB
Sensitivity:
0.530 - 2.000 MHz 10 uV (10 dB s/n) [actually tunes to 0.100 MHz]
2.000 - 30.0 MHz 1.0 uV LSB/USB
1.5 uV AM
1.5 uV FM
30.0 - 1000 MHz 0.5 uV AM, LSB, USB, NFM
0.75 uV WFM
1000 - 1300 MHz 1.0 uV
Search speed: 30 steps per second.
Tuning Steps:
WFM = 100KHz,50KHz
NFM = 100KHz, 50, 25, 20, 12.5,10, 9, 6.25, 5 & 1KHz
LSB/USB = 100KHz, 50, 25, 20, 12.5,10, 9, 6.25, 5 & 1KHz; 100Hz, 50Hz
Switchable Attenuator on different channels not just "all or nothing"
It's a bit of a power hog at 140 mA on its 4 AA batteries, but has a
10 mA power saving mode. However in standby mode it still takes 100
mA.
The Japanese Domestic version of the set has the following frequencies
omitted: 253-255, 262-266, 270-275, 380-382, 412-415, 810-834, 860-899,
915-960. For continuous coverage R103 (SMC) next to IC277 is removed.
There are NO "UK MODELS" or "JAPANESE MODELS" as some people are
trying to make out. The models available in the UK have had this mod
done, they are not different processors as I have heard certain people
say.
Comments:
NOTE: This scanner is not currently distributed in the United States.
ACE Communications, who mainly import the AOR line, stock the MVT-5000
and 7000 handhelds, but have balked twice at importing the 7100. At times
they have predicted they would carry it Spring-Summer 1993, for $579. If
you live in the US the only way to get this scanner now is to import it
yourself. Many UK dealers will ship worldwide using 2nd day FedEx.
First, this is a very capable scanner. It seems to have excellent
sensitivity down to 2 MHz or so (like the specs say) but even there, I
can actually get medium wave stations! (Unlike the R1 or AR1000). In
across-the-board sensitivity alone it flat out blows the doors off the
AR1000, and outdoes the PRO-43 a bit, too.
The radio comes with a swivel telescopic antenna ... no duckie. I'm
doing most of my non-HF testing using a rubber duckie. Amazingly,
though, I can get BBC at 6175 KHz using a rubber duckie alone!
Incredible... SSB actually =works=! I was copying hams on 20m in SSB
mode ... clearly. The carrier insertion oscillator is stable, and
having useable HF on a handheld is somewhat mind-blowing. With a
little fiddling, I can also demodulate inversion-scrambled cordless
phones using SSB.
The general dimensions are like a slightly taller PRO-43. However, the
plastic is soft and thin like the AR1000, and it lacks the stiff
internal metal frame of the PRO-43. The optional carry case is very nice.
It borrows the best features of the ICOM and AOR cases. Padded black
plastic with cutouts or detents for the side and top knobs and buttons.
Clear vinyl to cover the LCD and keypad. A top flap, secured by a velcro
strip, covers the top deck of the raido. Audio is very crisp - even bright
- and does not distort appreciably even going full tilt. The display
is large and readable but requires you to look at it from slightly below
for optimum contrast. It lacks the contrast control of the MVT-7000
and ICOM R-1. There is a defeatable beep ... I'm leaving it on until I
get used to the way the thing behaves (error conditions can show up
audibly if you do something wrong).
The feature set is like the ICOM R1 meets the AR1000 meets the
PRO2006. There are many, many data manipulation and convenience
features (like several ways to correct input errors, etc).
1000 memory channels - Memory channel will store any frequency, mode
and increment step. (eg. channel 1 123.75MHz, AM 25KHz steps while
channel 2 could be 5.616MHz, USB, 50Hz etc). Contents of a memory
channel can be transferred to manual mode in 2 key presses: FUNC +
M-VFO you can then manually tune/search up/down from displayed freq.
The memory channels are divided into 10 bands of 100. You can link up
to 4 scan banks together. The scanner does not store your choice of
scan banks; this is lost whenever you interrupt the scan process
(including powering off). However, you can also link 100 separate
channels from different banks using programmed scan, (whose contents
IS stored in memory) or all that use a specific mode (e.g. AM mode)
using mode scan (shades of the ICOM). There are 10 search bands which
are =NOT= linkable. Switching from one to the other, though, takes
only 2 swift keystrokes.
Memory channel backup is not permanent. It does not use an EEPROM like
the AR1000 or PRO-43; rather a backup battery like the R-1. The manual
says after the nicads are exhausted/removed, it will back up the
memories for about one week. Mine displayed CLEAR on the LCD when
first powered up; I assume this is what you get when the memories have
been lost or cleared.
Within the search banks you can program any 2 limits, any mode, any
increment step. There is no facility for automatically filling
memory channels with active frequencies found during a scan ("auto
memory write" or the like).
While searching you can easily change the mode or step size. You do
not have to re-program the whole search bank limits etc.
There is one priority channel (in addition to the 1000)
Up to 500 frequencies can be locked (passed as they call it) out
during search. These will be skipped even if you search in manual
mode. They are not just stored within the search bank.
The LCD display also includes a bar-graph signal strength meter like
the R1 (although it lacks the numerical scale of the R1 and, I fear,
the calibration too). It's somewhat topheavy - most strong signals go
near, or up to full scale. Still, a nice plus.
Many keys have 2 functions. The second function is printed below each
key. This is confusing, and since the additional function is printed
midway between the upper and lower key you sometimes get confused as
to which is associated with which. However, the key layout is logical
and so is easy to memorize; e.g. MODE change is the second function
associated with the STEP change key. This is important, as the two
settings interact (e.g. the step will change according to the "rules"
as you change modes, so you must often then go back and change the
step).
There is a metal eyelet jutting out of the top right side of the
scanner, for attaching a carry strap. It gets in the way when you want
to slide the scanner into the Pouch. Not as annoying as those blasted
Frankenstein things on the AR-1000, but I wish it were hinged rather
than being stiffly bolted onto the frame. It also comes with a sturdy
METAL belt clip which screws on.
I guess people are more interested in the minuses. Nothing is perfect,
and so here are what I perceive as drawbacks:
First and foremost, the 476 MHz area is unuseable where I am. It is
filled with intermod from pagers, even in low signal areas without an
antenna. It is doubtful that I have a defective unit ... I think
this is one of those weird interactions inherent in local conditions
and the design of the radio. There are reports of UK cell phone signals
appearing 400 MHz lower on the predecessor to this model, the MVT-7000.
Heck, for many people 160-161 is unuseable on the PRO-43, so there).
Frequency entry is quirky. The selected increment determines not only
the channel spacing, but whether or not an input frequency will be
rounded after you hit [ENTER]. For instance, to scan cordless phones
you would normally search 46.61 - 46.97 at 20 KHz increments. BUT ...
you can't input 46.61 with the increment set to 20 ... it gets rounded
to 46.60 to be consistent with the channel spacing the set "thinks" is
appropriate. Solution: use 10 KHz steps. This, however, will slow down
searching and, potentially, cause it to stop short of the center
of carrier during search (see below).
The above can make filling your scan memory channels time-consuming
unless you group the frequencies beforehand according to channel
spacing. For instance, to enter 453.8, 471.1625, and 869.01 into
consecutive memory channels, you would have to change the step for
keying in each of these values before putting them in memory.
Remember, the memory channels =also= store the increment selected.
In SSB mode you must manually account for the 1.5 KHz frequency
offset. I test the frequency accuracy of radios by zero-beating
against known AM transmitters in sideband mode (ECSS). In LSB mode,
WWV at 15000 KHz actually zero beats at 14998.5, and in USB mode at
15001.5. Various observers have found the calibration of the set
to be off by 300-1000 Hz from that actually displayed. I find that
acceptable for a battery operated portable intended for VHF/UHF use.
(Tweaking this could be difficult, since the radio will not operate
with the cover off - doing so unplugs the circuit boards from each
other, and may also cause a CPU reset).
Selectivity is a little broad for serious HF use. Especially on
SSB, where the same filter seems to be used as in AM mode. ISB
reception, for instance, would be impossible as the sidebands would
overlap. Lots of adjacent channel splatter in the 49m band, for
instance, in AM mode. Obviously this is not a DX rig. However it is
MORE than acceptable for casual listening to broadcasts and SSB
voice mode transmissions. Reportedly it works acceptably for FAX
and RTTY when used with an external demodulator.
As the set, like the AR1000, lacks "zero matic" circuitry, it may stop
short of the actual frequency in search mode, especially with narrow
(< 10KHz) search increments. A twist of the VFO knob or a push of the
up arrow key takes care of that. The S-meter makes it easy to figure
out where you are relative to the center of signal.
The light only stays on when the button is pushed. Pity. However, it
illuminates the whole keyboard a beautiful translucent green. Looks
like a Princess phone. Really neat!
The battery saver must be switched on manually when you are listening
to one channel for a long time. Any operation which is incompatible
with the super saver mode (like memory scan) will turn off the battery
saver. You must manually re-activate it if you want to use it again.
The delay is global (not per channel) and can't =really= be disabled.
When the delay is "off" you get a 2-second delay. When it's "on" you
get a 4-second delay. There is no "hold" (infinite delay) like on the
AR1000, but pushing the "monitor" button breaks squelch and will hold
the channel as long as you keep it pressed. However, there is a "skip"
mode which will play 5 seconds of a signal and them move on. This
would be particularly useful for sampling the shortwave broadcast
bands, where the huge number of signals would keep your finger poised
on the SEARCH button all the time.
Mike Schuster
schuster@panix.com
schuster@shell.portal.com
70346.1745@CompuServe.COM
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