Specifications

From January 2005 QST © ARRL
Table 3
Alinco DJ-C7T, serial number M000663
Manufacturer’s Specifications Measured in the ARRL Lab
Frequency coverage: Receive and transmit, as specified.
Receive, 88-108 MHz (WFM),
108-136 MHz (AM), 136-174 MHz,
380-512 MHz (FM);
transmit, 144-148 MHz, 420-450 MHz.
Power requirements: 3.7-6.0 V dc;
receive, 0.07 A; Receive, 0.1 A (max volume, no signal);
transmit, 0.32 A (max). transmit, 0.34 A. Tested at 6.0 V.
Receiver Receiver Dynamic Testing
Sensitivity: 12 dB SINAD, VHF, 0.2 µV; FM, 12 dB SINAD, VHF, 0.2 µV;
UHF, 0.25 µV; WFM, 0.7 µV. UHF, 0.23 µV;WFM, 100 MHz, 2.4 µV.
Two-tone, third-order IMD dynamic range: 20 kHz offset from 146 MHz, 52 dB,*
Not specified. 10 MHz offset from 146 MHz, 64 dB;
20 kHz offset from 440 MHz, 53 dB,*
10 MHz offset from 440 MHz, 69 dB.
Two-tone, second-order IMD dynamic range: VHF, 76 dB.
Not specified.
Adjacent-channel rejection: Not specified. 20 kHz offset from 146 MHz, 51 dB;
20 kHz offset from 440 MHz, 53 dB.
Spurious response: 60 dB. IF rejection, VHF, 96 dB, UHF, 109 dB;
image rejection, V/UHF, 78/41 dB.
Squelch sensitivity: Not specified. Threshold, VHF, 0.08 µV; UHF, 0.11 µV.
Audio output: 90 mW at 10% THD into 97 mW at 10% THD into 8 Ω (6 V);
8 Ω (6 V). 47 mW (battery).
Transmitter Transmitter Dynamic Testing
Power output: 0.5 W (6 V); 0.3 W (battery). 146 MHz, 0.3 W; 440 MHz, 0.3 W with
EBP-58N battery pack;
146 and 440 MHz, 0.47 W; with 6 V dc.
Spurious signal and harmonic suppression: VHF, 52 dB; UHF, 60 dB.
60 dB. Meets FCC requirements.
Transmit-receive turnaround time (PTT release Squelch on, S9 signal, V/UHF, 98/85 ms.
to 50% of full audio output): Not specified.
Receive-transmit turnaround time (“tx delay”): VHF, 140 ms; UHF, 170 ms.
Not specified.
Size: 3.8 × 2.3 × 0.6 inches (HWD); weight, 3.6 ounces.
*Measurement is noise-limited at the value specified.
Bottom Line
An awesome pop-in-your-pocket,
take-anywhere dualband mini
handheld that’s a decent ham band
performer and a whole bunch of fun.
duty handheld in areas where various VHF
and UHF signals—not just amateur—
proliferate. The receiver’s dynamic range
hovers in the low 50 dB range in both ham
bands. This level of performance does not
offer a great deal of protection against
infiltration from nearby in-band signals—
or even signals in adjacent commercial
bands, including Public Safety, paging
systems and even broadcasters.
Speaking of specs: The manual that
came with this radio includes a specifi-
cation table different from what the Alinco
engineers intended. The correct specs can
be found on their Web site. When we first
tested a sample we let the manufacturer
know that it wasn’t meeting their specs and
they determined that their document folks
had grabbed the wrong numbers. Our Table
3 reflects the updated specs.
Catching Up With the
“New Generation”
In the C7T, active amateurs—and
especially frequent travelers—will find a
multi-featured, extremely small and
lightweight, albeit flea-power, VHF/UHF
transceiver that they literally can take
anywhere—except swimming. Over the
few weeks of running it through its paces,
I’ve tossed it into my briefcase or just
stuck it into a shirt or jacket pocket to
take along on the road (remembering not
to send it to the cleaners or laundry). At
3.6 ounces (including the battery) and
less than 4 inches tall, it’s still “wicked
rugged,” as New Englanders say. As the
manual notes, however, while the C7T
has been tested for “anti-shock and/or
against drops for daily use,” it is not built
to military specifications.
Once you’ve pocketed the C7T, the only
thing to remind you it’s there likely will
be the nearly 4.5-inch flex antenna sticking
out. By the way, Alinco used an SMA
antenna jack this time, so you can swap
out for a larger antenna if you’d prefer.
The C7T sports a sturdy, gently tapered
two-tone (silver-gray and black) plastic
case. The 3.7 V, EBP-58N 600 mAh
lithium-ion battery, about the size of some
of the larger-format digital camera storage
cards but about twice as thick, snaps neatly
and securely onto the bottom rear of the
unit. It’s very simple to remove and
replace, should you spring for a spare.
The LCD display, while not back
lighted, is sizeable for such a tiny
transceiver. About 1.5 inches across and
a half-inch high, it dominates the upper
quarter of the transceiver’s front panel.
The frequency readout font is large and
highly visible, even from a couple of feet
or so away. You can even see the smaller
memory channel number and the vertical
uncalibrated bar graph style S/power
meter, which I didn’t find terribly useful.
In addition to frequency and memory
number, the display conveys lots of other
vital information. The display indicates
mode and whether certain features are
enabled, such as APO (auto power off)—
the C7T sends END three times in Morse
when it’s about to shut itself off—or
BS
(no, it means “battery save”)—a tiny bat-
tery icon tells you you’re running out of
steam. An asterisk (*) indicates you’re in
repeater mode. The typical + and – sym-
bols tell you the repeater offset direction,
while T/SQ symbols let you know when
CTCSS tone (or European tone burst)
and/or tone squelch is enabled.
Immediately below the display are five
multifunction pushbuttons, stylishly ar-
rayed in two slight arcs—three above and
two beneath—just above the speaker grille,
which occupies the rest of the front panel.
Topping off the transceiver, in addition to
the rubber duckie, is a multifunction rotary
control (which Alinco refers to as the
“dial”). On the left side are the push-to-talk
and the
MONI(tor)/STEP buttons.
A tiny front panel LED glows red
when you’re transmitting and green when
a signal breaks squelch.
The unit has two jacks. The MIC/EAR
jack accepts a small (mono) plug, not the
more common 3.5 mm variety (some other
transceivers have gone to these as well).
Another tiny coaxial jack on the right side