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Product Review and Short Takes from QST Magazine
November 2009
Product Reviews:
ICOM IC-7600 HF and 6 meter transceiver
Short Takes:
Copyright © 2009 by the American Radio Relay League Inc. All rights reserved.
848800930.050.png
Key Measurements
Summary
product review
ICOM IC-7600 HF and
6 Meter Transceiver
121
122
70
140
20
20 kHz Blocking Gain Compression (dB)
99
102
70
140
2
2 kHz Blocking Gain Compression (dB)
104
,
106
50
110
20
20 kHz 3rd-Order Dynamic Range (dB)
,
88
50
110
IC-7700 and IC-7800, and all offer a choice
of faux meter styles, too — standard (analog),
edgewise and bar.
If you’re already familiar with the PRO
line, you’ll feel right at home with the ’7600.
If you’re a newcomer, you’ll find the IC-7600
has a gentle learning curve. ICOM’s plain-
language menus are a major reason for this.
2
Reviewed by Rick Lindquist, WW3DE
National Contest Journal Managing Editor
2 kHz 3rd-Order Dynamic Range (dB)
29
Already widely known as the “PROIV,”
ICOM’s IC-7600 HF+50 MHz transceiver
is an apparent and worthy successor to the
extremely popular IC-756PROIII. 1 Whatever
ICOM’s designation, the IC-7600 is a terrific
performer with a fine complement of useful
tools for DXing and contesting! Granted,
the IC-7600 is not totally new and different
with respect to the older PROIII and the more
recent IC-7700 and IC-7800 transceivers. 2
This review will include some comparisons,
as appropriate, to the models with which it
shares some DNA. Let’s see how the IC-7600
stacks up.
,
-40
31
+35
20
20 kHz 3rd-Order Intercept (dBm)
Wider is Better
Legends and icons on the 5.8 inch 400×240
pixel display feature clean, straight lines. For
example, on the PROIII, the current operating
mode appears in a stylized horizontal tube,
sort of like a hot dog or a blimp. The MODE
indicator on the IC-7600 is a smallish but very
visible blue rectangle with white letters. The
RIT/XIT readout is smaller than the PROIII’s,
and it’s in a different display location that I
never quite got used to (the RIT/XIT readout on
the PROIII places larger numerals directly be-
low the last three digits of the main frequency
readout). As with the IC-7700, the IC-7600
offers only an “A” or a “B” display — one es-
sentially an inverse of the other — plus three
font choices — basic, italic and round. The
basic and round styles are quite similar, but
the round characters are a bit fatter.
After complaining about the limited view-
ing angle of the IC-7700’s otherwise excellent
display, we’re pleased to note that the IC-7600
offers excellent horizontal and vertical vis-
ibility from just about any angle. The IC-7600
does not provide for connecting an external
VGA video display, however.
,
13
-40
+35
2
2 kHz 3rd-Order Intercept (dBm)
,
-31
TX
-20
-35
Transmit 3rd-Order IMD (dB)
A Stylish Makeover
On its face, the ’7600 looks similar to its
PRO series forbears, the most notable excep-
tion being a larger and improved LCD display
(Figure 1). My wife liked the new display after
comparing the PROIII and the ’7600 side by
side, so it must be better. The IC-7600 is es-
sentially the same convenient size and weight
as the PROIII with a similar front-panel lay-
out. Some may mourn the replacement of the
PROIII’s moving-coil meter with an excellent
digital emulation on the ’7600’s larger display.
ICOM has a similar implementation on the
,
-48
TX
-70
-20
Transmit 9th-order IMD (dB)
pr041
Key:
80 M
Dynamic range and intercept
values with preamp off.
Intercept values were determined
using -97 dBm reference
20 M
Bottom Line
1 R. Lindquist, N1RL, “ICOM IC-756PROIII
HF/6 Meter Transceiver,” Product Review,
QST , Mar 2005, pp 56-59. QST Product
reviews are available on the Web at
www.arrl.org/members-only/prodrev /.
2 R. Lindquist, N1RL, “ICOM IC-7700 HF and
6 Meter Transceiver,” Product Review, QST ,
Oct 2008, pp 41-47.
The IC-7600 represents a superb
synthesis of ICOM’s popular PROIII
and the IC-7700/7800 transceivers,
both in style, features and capability.
Another winner!
Cleaner Lines
Aside from its fabulous display, the
’7600’s uncluttered front-panel has a smooth,
Mark J. Wilson, K1RO
Product Review Editor
k1ro@arrl.org
From November 2009 QST © ARRL
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semi-gloss surface that may be easier to clean
than the PROIII’s. The rest of the box closely
resembles the PROIII’s, but without the
sunken front apron and with sharper, rather
than rounded, features. The ’7600’s larger
knobs — the hefty, clean-edged rubber-ringed
tuning knob is like the one on the IC-7700 —
ease their use.
The radio’s bright-white control legends
are larger and easier to read than those on the
PROIII. While I do appreciate the PROIII’s
oversized red keypad numerals for entering
a frequency, those on the ’7600’s keypad,
though smaller, remain easy to read, and the
keypad buttons are larger to start with. In
addition, the “pointer” markings on the IC-
7600’s knobs are simple to see, and the rings
on concentric controls contrast ever so slightly
in hue and sheen. All knobs — even the stem
controls — are fatter than the PROIII’s. On
the other hand, the stem controls are in a more
congested location on the ’7600 because of
its larger display. The IC-7600 overcomes
the absence of contrasting colors on knobs
and front panel legends in part by employing
variations in button styles and shapes.
One minor unintended consequence of
the front-panel rearrangement: The TRANS-
MIT , TUNER and MONITOR buttons are in a
horizontal line on the left-hand side of the
panel, above the AF GAIN control. On several
occasions when I wasn’t paying close-enough
attention, I hit the TRANSMIT button instead
of the neighboring TUNER button, which has
a status LED. The MP-W and MP-R scratchpad
memory buttons also can blend in with their
neighbors, so you have to pay closer attention
to ensure you’re not pressing the adjacent
hard memory buttons. On the PROIII, the
scratchpad memory keys are not only larger
and off by themselves, but are in a contrast-
ing light gray.
Some additional visibility issues are worth
a mention. The right-pointing arrows on the
seven multi-function keys lining the left hand
side of the display blend into the background,
especially in soft light; these are not filled in
with a contrasting color to make them easier to
distinguish one from the other, much less to see
them at all in low light. In a similar vein, leg-
ends on the six LCD function keys just below
the display can be difficult to tell apart.
Just below the LCD function keys are six
mode switches. In addition to the FILTER and
EXIT/SET keys, the ’7600 offers individual
mode keys for SSB , CW , RTTY/PSK and AM/
FM . As a PROIII user, I appreciated not having
to share the CW mode with the RTTY key.
Unbundling the CW key also means you can
quickly swap from CW to CW-R when flipping
your tuning direction, as I often do during
search-and-pounce (S&P) contest operation.
The UP and DOWN buttons for
memory scrolling are positioned right next
to the main tuning knob, making them more
obvious and handy. Depending upon how
ham-handed (get it?) you are, their placement
may make the tuning knob more vulnerable to
the inadvertent jog when using them. I didn’t
have any problems in this regard.
I was pleased to find a feature on the
’7600 that announces signal strength reading,
frequency and mode in an agreeable female
voice. It’s possible to deactivate the S meter
and mode components. This is standard equip-
ment on the IC-7700 too. The ’7600 back
panel looks about as you would expect and is
shown in Figure 2.
shapes for SSB/SSB-D (data) and CW that
are independent of the shape setting on the
FILTER menu, but within strict limitations that
favor CW or AFSK modes only.
Here’s the thing: You can separately set
CW filters 500 Hz or narrower and 600 Hz
or wider to default automatically either to
soft or sharp. On SSB-D (for AFSK), it’s
possible to have the radio default automati-
cally to soft or sharp when the filter setting
is greater than 600 Hz. The same is possible
for SSB, although whichever shape you set
becomes the default for any practical SSB
filter. It would be far more useful for typical
SSB operation if, for example, you could
set the filter shape to default automatically
to sharp when the filter setting is less than
2 kHz or so, not 600 Hz. In any case, it’s just
a couple of button presses to change the filter
shape to whichever setting you want.
How Much Would You Pay . . .?
As the late TV huckster Billy Mays
might have hollered in another life, “How
many times have you been embarrassed by
transmitting on top of the DX when you
thought you were in split? Well, worry no
more!” The IC-7600’s mother of all SPLIT
indicators makes it really difficult not to
know when you’re working split. The
nearly 1-inch-long LED indicator along the
top edge of the display looks like a mini-
fluorescent lamp. An on-screen SPLIT legend
of contrasting shade accompanies the bright
light. ICOM also has placed the TX , RX and
DUAL WATCH LEDs above the display where
they belong; display icons reiterate the status
of these functions.
In a similar “isn’t that amazing !” vein, the
IC-7600 lets you type in desired text for CW
and digital memories using a USB (universal
serial bus) keyboard. This is a vast improve-
ment over having to “dial” in the memory
contents one character at a time using the main
tuning knob, although it’s a bit of a hybrid
system. To enter letters, you still must press
the upper-case or lower-case TEXT button on
the transceiver’s display while in edit mode.
In like fashion, to enter numbers you still must
press the 123 button. Pressing SHIFT on the
keyboard doesn’t work.
Diddles
While the PROIII can decode RTTY on its
display and transmit RTTY from memories
without the use of a PC, the IC-7600 offers
full transmit and receive capability in RTTY
and PSK31. Just plug a USB keyboard into
the radio, bring up the DECODE screen for the
relevant mode and you’re ready to roll, digi-
tally speaking. Unfortunately this capability
doesn’t extend to CW.
The DECODE screens for RTTY and
PSK31 feature helpful, but diminutive, water-
fall displays for finding and tuning signals. The
PSK31 screen includes a tiny, ever-changing
phase readout to lend further assistance, plus
AFC and NET; the RTTY tuning indicator is in
the upper right hand corner of the main display.
This was the simplest and easiest RTTY and
PSK31 experience I’ve ever had (well, at least
since reviewing the IC-7700)!
The PSK31 and RTTY waterfall displays
cover 1195 to 1805 kHz (610 Hz) with the
center at 1500 (there’s a choice of 1000,
1500 and 2000 Hz in both digital modes)
— quite a bit less real estate than you’ll
find on a PC screen with DigiPan or simi-
lar software. While using narrow filter set-
tings you must tune manually from waterfall
to waterfall; otherwise, you won’t always see
them, just hear them. For RTTY, the waterfall
display covers 1905 to 2515 (also 610 Hz)
with a twin-peak waveform that lets you tune
signals with precision. It’s possible to adjust
and read out the THRESHOLD .
Text appearing on the screen — red for
transmitted text and green for received — is
quite small, as is the “window space” avail-
able. Pressing the WIDE button gives you
more on-screen elbow room, but if you’ve
enabled the mini spectrum scope (the only
one available in digital modes), it yields to
the larger text window. In addition, lines of
text don’t always break appropriately, so you
need to pay closer attention. Copy on the
IC-7600’s decoder screen seemed compa-
Shape Shifting
ICOM has imbued the IC-7600 with top-
notch DSP IF filters, but the implementation
is not without some minor wrinkles. Basic IF
filter selection is essentially identical to the
PROIII’s setup with the exception of AM. On
the IC-7600, you can set the AM passband
between 200 Hz (!) and 10 kHz in 200 Hz
steps for a total of 50 discrete filter pass-band
widths plus full dual pass-band tuning. On the
PROIII, the IF filter passband choices for AM
are fixed at 9, 6 or 3 kHz, with a simple IF (ie,
single pass-band) shift available. For FM the
IC-7600 offers three fixed passband choices,
15, 10 and 7 kHz, just as on the PROIII.
To select a basic filter shape (sharp or soft)
requires going to the FILTER menu, rather than
to the DSP menu as on the PROIII. If you
pick SHARP or SOFT on the FILTER menu,
that shape setting applies to all three avail-
able filter bandwidth settings. The FILTER
SHAPE SET menu lets you configure filter
From November 2009 QST © ARRL
rable to what I was seeing via the MMTTY
engine on my PC’s display.
Using submenus on the DECODE screens,
it’s possible to save RTTY or PSK31 memo-
ries on a USB compatible medium, such as a
flash drive (you can also save voice memories
this way, but not CW). The RTTY and PSK31
memories are separate.
Contesting in RTTY and CW with the
’7600 (using a computer logger and RTTY
engine) was lots of fun, especially given the
exceptional receiver. In these higher duty
cycle modes — especially RTTY — the radio
got quite warm to the touch, although the
on-screen temperature gauge remained well
within the normal range. The cooling fan is
barely noticeable.
table 1
icoM ic-7600, serial number 0201165
Manufacturer’s Speciications
Measured in the ARRL Lab
Frequency coverage: Receive, 0.03-60 MHz;
Receive, as speciied;
transmit, 1.8-2.0, 3.5-4, 5.3305, 5.3465,
transmit, as speciied.
5.3665, 5.3715, 5.4035, 7-7.3, 10.1-10.15,
14-14.35, 18.068-18.168, 21-21.45,
24.89-24.99, 28-29.7, 50-54 MHz.
Power requirement: 13.8 ±15% V dc; receive,
13.8 V dc; receive 2.4 A (max audio);
3.5 A (max audio); transmit, 23 A (100 W out).
transmit, 18 A (100 W out). Operation
conirmed at 11.7 V (83 W output).
Modes of operation: SSB, CW, AM, FM,
As speciied.
RTTY, PSK.
Receiver
Receiver Dynamic Testing
SSB/CW sensitivity: 2.4 kHz bandwidth,
Noise loor (MDS), 500 Hz bandwidth:
10 dB S/N: 0.1-29.99 MHz, 0.15 µV;
Preamp
off
1
2
50-54 MHz, 0.12 µV.
0.137 MHz
–124
–126
–129 dBm
0.505 MHz
–130
–138
–141 dBm
1.0 MHz
–130
–138
–141 dBm
3.5 MHz
–131
–139
–141 dBm
Magic Decoder Button
ICOM’s APF (audio peak filter) skipped
radio generations. First appearing (in a some-
what different implementation) on ICOM’s
original IC-756, APF turned up again on
the IC-7800 and IC-7700 transceivers. Its
incarnation on the IC-7600 includes a new
twist. The TPF (twin-peak filter) for RTTY,
an RTTY FIL menu selection on the PROIII,
has been promoted to the front panel APF/
TPF button on the IC-7600. More on that
feature in a bit.
Pressing the APF/TPF button in CW im-
poses one of three mini audio-peaking filters
— 80, 160 or 320 Hz or NAR , MID and WIDE
— atop whatever DSP IF filter settings are in
play. To hear much of a difference, the IF filter
must be set to a passband that’s significantly
greater than the APF setting. For example,
you might use the 80 Hz setting when you’ve
got the IF filter set to, say, 150 Hz. When you
press the button, the current setting appears
briefly on screen, although you can disable
this. You can choose either a “soft” or “sharp”
APF shape via a menu.
On CW the effect of the APF is not espe-
cially dramatic when you’ve already selected
a narrow IF filter, but it does help further quell
background noise. The noise reduction pro-
cessor ( NR ), readily at hand, can do the heavy
lifting in that department, although the APF
seems to boost signal-to-noise ratio. It’s at its
best when you’re using, say, a 500 or 800 Hz
IF DSP filter and need a little more help.
For RTTY, the TPF is exceptionally ef-
fective. Pressing the APF/TPF button in
RTTY mode alters the radio’s AF response
by punching up the mark and space frequen-
cies, 2125 and 2295 Hz. During the July
North American QSO Party RTTY event,
the TPF brought “S-nuttin’” signals (as we
called the weak ones while I was growing
up in Northern New Jersey) right out of the
mud so they’d print. The ’7600 lets you use
the TPF in tandem with any of the three IF
filter bandwidths (plus soft or sharp contour)
you’ve set up in advance, and you can take
full advantage of the dual-passband IF shift
14 MHz
–131
–139
–141 dBm
50 MHz
–132
–141
–143 dBm
Noise igure: Not speciied.
14 MHz, preamp off/1/2: 16/8/6 dB
AM sensitivity: 6 kHz bandwidth, 10 dB S/N:
10 dB (S+N)/N, 1-kHz, 30 % modulation:
0.1-1.799 MHz, 6.3 µV; 1.8-30 MHz, 2 µV;
Preamp
off
1
2
50-54 MHz, 1.6 µV.
1.0 MHz
1.70
0.65
0.55 µV
3.8 MHz
1.50
0.59
0.50 µV
50 MHz
1.60
0.62
0.54 µV
FM sensitivity: 15 kHz bandwidth, 12 dB SINAD: For 12 dB SINAD:
28-30 MHz, 0.5 µV; 50-54 MHz, 0.3 µV.
Preamp
off
1
2
29 MHz
1.05
0.38
0.29 µV
52 MHz
0.62
0.24
0.22 µV
Spectral display sensitivity, preamp off/1/2:
–105/–116/–121 dBm.
Not speciied.
Blocking gain compression: Not speciied.
Gain compression, 500 Hz bandwidth*
20 kHz offset
5/2 kHz offset
Preamp off/1/2
Preamp off
3.5 MHz
121/122/117 dB
111/99 dB
14 MHz
122/123/120 dB
113/102 dB
50 MHz
119/121/120 dB
105/98 dB
Reciprocal mixing (500 Hz BW): Not speciied.
20/5/2 kHz offset: –105/–91/–82 dBc.
ARRL Lab Two-Tone IMD Testing*
Measured
Measured
Calculated
Band/Preamp
Spacing
Input Level
IMD Level
IMD DR
IP3
3.5 MHz/Off
20 kHz
–27 dBm
–131 dBm
104 dB
+25 dBm
–13 dBm
–97 dBm
+29 dBm
14 MHz/Off
20 kHz
–25 dBm
–131 dBm
106 dB
+28 dBm
–12 dBm
–97 dBm
+31 dBm
0 dBm
–61 dBm
+31 dBm
14 MHz/One
20 kHz
–33 dBm
–139 dBm
106 dB
+28 dBm
–20 dBm
–97 dBm
+19 dBm
14 MHz/Two
20 kHz
–39 dBm
–141 dBm
102 dB
+12 dBm
–24 dBm
–97 dBm
+13 dBm
14 MHz/Off
5 kHz
–37 dBm
–131 dBm
94 dB
+10 dBm
–20 dBm
–97 dBm
+19 dBm
0 dBm
–50 dBm
+25 dBm
14 MHz/Off
2 kHz
–43 dBm
–131 dBm
88 dB
+1 dBm
–24 dBm
–97 dBm
+13 dBm
0 dBm
–31 dBm
+16 dBm
50 MHz/Off
20 kHz
–29 dBm
–132 dBm
103 dB
+23 dBm
–15 dBm
–97 dBm
+26 dBm
( PBT ) feature. On the PROIII with the RTTY
tuning meter enabled, you can choose just
one of five possible IF bandwidths for RTTY,
you’re restricted to a single-passband IF shift
and switching away from the RTTY filter set-
ting disables the TPF .
The radio’s NOTCH operates in a some-
what similar fashion to the APF/TPF , al-
though the manual notch is adjustable via a
front-panel control. You can pick from NAR ,
MID or WIDE notch filters. As with the APF/
TPF feature, enabling the notch by pressing
From November 2009 QST © ARRL
848800930.048.png 848800930.049.png
seems to generate less crud than many less-
capable noise blankers impose. I was able
to use the NB in conjunction with the noise-
reduction feature to substantially reduce noise
that included impulse spikes apparently ema-
nating from a nearby solar panel installation.
Very aggressive/extreme settings like these
can add considerable distortion to desired
signals, however.
Receiver
Receiver Dynamic Testing
Second-order intercept: Not speciied.
Preamp off/1/2, +63/+63/+59 dBm.
DSP noise reduction: Not speciied.
Variable, 15 dB maximum.
Notch ilter depth: Not speciied.
Manual notch: 75 dB;
auto notch: 57 dB; attack time: 37 ms.**
FM two-tone, third-order IMD dynamic range:
20 kHz offset, both preamps on:
Not speciied.
29 MHz, 72 dB ; 52 MHz, 72 dB .
10 MHz channel spacing: 52 MHz, 110 dB.
Time Warp?
Others may appreciate the record/play
feature more than I did. This feature, which
lets you record off-the-air audio and then play
it back, on or off the air, did not improve much
with the jump from one model to the next. It
could be convenient when helping someone
adjust their audio or compare antennas, but
you’ll have to figure out how it works first.
The manual’s description of this feature is
difficult to comprehend, and using it is far
from intuitive.
The IC-7600 provides separate front-
panel REC and PLAY buttons. It records
continuously, so it can replay the 15 seconds
of audio that you heard before you pushed the
REC button. There’s no on-screen indication
that you’re in record mode (the PROIII has
a blinking on-screen REC indicator). At the
default setting, the radio will play back up
to 15 seconds per “cut.” The VOICE menu
indicates the frequency and recording date
of each cut.
S-meter sensitivity: Not speciied.
S9 signal at 14.2 MHz: preamp off, 79.4 µV;
preamp 1, 33.5 µV; preamp 2, 16.4 µV.
Squelch sensitivity: SSB, CW, RTTY, 3.2 µV;
At threshold, both preamps on:
FM, 0.3 µV.
SSB, 1.2 µV; FM, 29 MHz, 0.13 µV;
52 MHz, 0.12 µV.
Receiver audio output: >2 W into 8 at
2.13 W at 10 % THD into 8 .
10% THD.
THD at 1 V RMS, 0.25%.
IF/audio response: Not speciied.
Range at –6 dB points (bandwidth):
CW (500 Hz): 336-803 Hz (476 Hz);
Equivalent Rectangular BW: 486 Hz;
USB (2.4 kHz): 228-2735 Hz (2507 Hz);
LSB (2.4 kHz): 228-2725 Hz (2497 Hz);
AM (10 kHz): 130-4600 Hz (8940 Hz);
AM (6 kHz): 130-3150 Hz (6040 Hz)
Spurious and image rejection: HF and 50 MHz,
First IF rejection, 14 MHz, 108 dB;
(except IF rejection on 50 MHz): >70 dB.
50 MHz, 84 dB. Image rejection,
14 MHz, 121 dB; 50 MHz, 118 dB.
Transmitter
Transmitter Dynamic Testing
Power output: HF and 50 MHz: SSB, CW, RTTY,
HF: CW, SSB, RTTY, PSK, FM,
PSK, FM, 2-100 W; AM, 1-30 W.
typically 1.2-105 W; AM, 0.7-32 W.
50 MHz: CW, SSB, RTTY, PSK,
FM, 1-100 W; AM, 0.5-29 W.
Spurious-signal and harmonic suppression:
HF, 70 dB; 50 MHz, more than 70 dB.
>50 dB on HF, >63 dB on 50 MHz.
Meets FCC requirements.
SSB carrier suppression: >40 dB.
>70 dB.
Undesired sideband suppression: >55 dB.
>70 dB.
You and Me and Rain on the Roof
The inclusion of selectable roofing filters
several years ago marked a sea change in
Amateur Radio transceiver design. As with
many of its peers, the PROIII did not have this
feature — it used a single 15 kHz wide roofing
filter. The implementation on the IC-7600 is
essentially identical to that of the IC-7700,
with a choice of three crystal band-pass roof-
ing filters at 15, 6 and 3 kHz in the first IF.
ARRL Lab Test Engineer Bob Allison,
WB1GCM, suggests thinking of a roofing
filter as “a first line of defense against any
adjacent strong signals, especially multiple
signals.” The roofing filter follows the first
mixer, and it has the effect of reducing the
passband of the first IF, he explains.
On the IC-7600 you can impose a roofing
filter bandwidth setting of 15 kHz, 6 kHz or
3 kHz on any DSP IF filter setting. Allison
says being able to insert a narrower roofing
filter helps to reduce overloading in the IF
amplifier and mixers that follow; the DSP
IF filtering takes over to help with the rest.
So, the narrower roofing filter does not de-
termine the receiver’s ultimate IF bandwidth
but will enhance dynamic range since all but
the strongest adjacent signals are attenuated
before hitting the receiver’s first IF.
“This is very desirable for CW, SSB and
digital modes,” Allison asserts. He allows,
however, that no roofing filter is completely
Third-order intermodulation distortion (IMD)
3rd/5th/7th/9th order (worst case band):
products: Not speciied.
HF: –31/–35/–41/–48 dB;
50 MHz: –31/–34/–45/–55 dB.
CW keyer speed range: Not speciied.
6 to 48 WPM.
CW keying characteristics: Not speciied.
See Figures 3 and 4.
Transmit-receive turnaround time (PTT release
S9 signal, 16 ms.
to 50% audio output): Not speciied.
Receive-transmit turnaround time (tx delay): SSB, 21 ms; FM, 11 ms.
Not speciied. Unit is suitable for use on AMTOR.
Composite transmitted noise: Not speciied. See Figure 5.
Size (height, width, depth): 4.6 × 13.4 × 11 inches; weight, 22 pounds.
Price: $3999.
*Receiver testing was performed with the bandwidth set to 500 Hz and 3 kHz rooing ilter.
ARRL Product Review testing now includes two-tone IMD results at several signal levels.
Two-Tone, 3rd-Order Dynamic Range igures comparable to previous reviews are shown
on the irst line in each group. The IP3 column is the calculated third-order intercept point.
Second-order intercept points were determined using –97 dBm reference.
**Single beat note. Reduces two beat notes by 45 dB with attack time of 106 ms.
Measurement was noise-limited at the value indicated.
Default values, sharp setting. Bandwidth is variable; smooth setting is available.
CW bandwidth varies with PBT and pitch control settings.
the button briefly flashes the current notch
setting on screen, although you can disable
this too. In addition to the manual notch, an
automatic notch is available in SSB and AM
mode. It’s extremely effective against multiple
heterodynes, although as broadcasters migrate
from the amateur bands, these are becoming
less of an issue.
The IC-7600’s digital noise blanker not
only lets you set NB level but NB depth and
width. This feature is helpful for pulse-type
noise, such as ignition interference, and it
From November 2009 QST © ARRL
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