Instruction manual

From March 2009 QST © ARRL
cable. A single fused red wire from the sensor
connects to 12 V dc for the meter lamps.
I was puzzled by the name “All Time Multi
Media Monitor” that adorns the front panel.
The 4 page Japanese language instruction
manual did not help my understanding of
this term, but the illustrations were sufficient
to hook up and use the meter. This was the
only unit tested that lacked a mechanical ad-
justment on the front panel to zero the meter
movement.
Accuracy could have been a bit better at
the lower ranges but it still gives reasonable
power indication and importantly, a good
SWR reading at a glance — perfect for a
mobile environment.
US distributor: NCG Company, 15036
Sierra Bonita Ln, Chino, CA 91710; tel 909-
393-6133; www.cometantenna.com.
DAIWA CN-801 HP
The CN-801 HP uses
a large cross needle meter
with pleasing pale blue meter
lamps, making it stand out
in any ham shack. Fairly
heavy as wattmeters go, this
giant size gray metal unit is
ruggedly built and comes
with removable rubber side
bumpers, a useful feature
that may prevent damage in
the field.
Its range of 1.8 to 200 MHz
is the widest in this group,
with forward power scales of
20, 200 and 2000 W selected
by the front panel RANGE
switch. This active wattmeter
must be connected to a dc
supply for PEP measurements
but will read average power
an RF sensing circuit dis-
connects the battery when
the AWM-30 is not mea-
suring power. The ON/OFF
switch controls only power
to the lamps.
The instruction sheet is
four pages and includes a
schematic diagram. Out of
the box, the AWM-30 didn’t
work because the meter lugs
were shorted to the chassis.
It worked fine after I moved
them, and Ameritron told
me they would look out for
this problem.
Accuracy at the 5 W
level was not as good as the
other meters tested, perhaps
because the AWM-30’s low-
est power range is 300 W.
It’s fine at the 100 W level
and slightly high at 1 kW.
The SWR accuracy was good.
Manufacturer: Ameritron, 116 Willow
Rd, Starkville, MS 39759; tel [phone];
www.ameritron.com.
COMET CMX-1
This cross needle meter reads average
power only. A separate power sensor and
lightweight, compact construction make the
CMX-1 a good choice for mobile work. Its
colorful backlit meter face and dark gray plas-
tic case make the CMX-1 a fine decoration
on any dashboard. Rear panel channels allow
you to neatly tuck in the sensor cable for flush
mounting, and adhesive hook-and-loop strips
are included. The bottom of the meter unit ac-
cepts a threaded mounting post with the same
dimensions as a common camera tripod, but
you provide the mounting hardware.
Specified to work at 1.8 to 60 MHz, the
CMX-1 offers forward power ranges of 30,
300 and 2000 W. The meter face has forward
power tick marks in 1 W steps up to 15 W and
2.5 W steps from 15 to 30 W. Multiply by 10
or 100 for the higher power ranges.
There are four unobtrusive pushbuttons to
the right of the meter. Three select the power
range. The other is a momentary contact
VOLTAGE, switch for quick measurement of
the supply voltage. A small sliding switch on
the right side turns the meter illumination on
and off. The meter housing is compact, but the
meter face is 2.5 × 2 inches — large enough
for easy and quick readings. It’s also rendered
in color, with green lines for SWRs of 1.5:1 or
lower and red lines for higher readings.
The CMX-1’s 6 foot cable detaches at
the sensor with a 5 pin DIN connector, and
Comet offers an optional sensor extension
Comet CMX-1
Frequency range 1.8-60 MHz
Power range 1-2000 W
Power requirement 11-15 V dc, 200 mA (lamps only)
PEP measurement None
Size (height, width, depth) 3 × 4.25 × 1.5"
Price $170
Actual Power (W) Indicated Power (W)
Frequency (MHz) 2 14 28 50
5 W CW 4.0 4.0 3.8 3.8
5 W 50% N/A for non-PEP meter
100 W CW 93 94 91 92
100 W 50 N/A for non-PEP meter
100 W two-tone N/A for non-PEP meter
1 kW CW 1070 1140 1050 –
1 kW 50% N/A for non-PEP meter
1 kW two-tone N/A for non-PEP meter
SWR Accuracy
1:1 SWR 1.0:1 1.0:1 1.0:1 1.0:1
2:1 SWR 1.9:1 1.9:1 1.9:1 1.8:1
Insertion loss (dB) <0.1 <0.1 <0.1 <0.1
– = Not measured.
Daiwa CN-801 HP, serial number 2003
Frequency range 1.8-200 MHz
Power range 1-2000 W
Power requirement 13.8 V dc, 70 mA
PEP measurement Active
Size (height, width, depth) 4.5 × 6.125 × 4.5"
Price $155
Actual Power (W) Indicated Power (W)
Frequency (MHz) 2 14 28 50 144
5 W CW 4.9 4.9 4.8 4.7 5.4
5 W 50% 6.2 5.5 5.3 5.3 6.3
100 W CW 98 99 94 97 98
100 W 50% 106 101 97 102 103
100 W two-tone – 96 – – –
1 kW CW 1030 1040 990 – –
1 kW 50% 1180 1300 1130 – –
1 kW two-tone – 1050 – – –
SWR Accuracy
1:1 SWR 1.0:1 1.0:1 1.0:1 1.0:1 1.0:1
2:1 SWR 2.1:1 2.0:1 2.1:1 2.0:1 2.0:1
Insertion loss (dB) <0.1 <0.1 <0.1 <0.1 0.13
– = Not measured.