Yupiteru MVT-7100 Review
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
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, andvarious 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).
Choose 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 01274 732146 (From U.S. 011 44 1274 732146)
Fax 01274 722627 (From U.S. 011 44 1274 722627)
Please send any comments, corrections, or updates on this
review to Howard Bornstein
Please note the Javiation address and contact details have changed since this review was published: