Surecom SW-112 HF Instruction Manual

V.S.W.R. & POWER METER
Instruction Manual
Note: that the front and rear panel data of the two models are different.Subject to change without prior notice
How to Use :
The S.W.R.meter is connected between the radio (TX) and the antenna,
as close as possible to the transceiver (use a cable of max. 40 cm like Test Jumper.
(Not include)
1)Check all connections.
2)Press the key of the microphone PTT to pass into transmission and keep it in this
position.
3)Read data of S.W.R. / Forward watt / Reflected watt
What is a high SWR reading?
1.5 -> 2.0. Your antenna is acceptably tuned and should work fine.
2.0 -> 3.0. Your SWR reading is slightly high, it shouldn't damage your radio
but you should try and tune your antenna to bring down your SWR
reading.
Above 3.0 or more . Your antenna isn't tuned acceptably and could damage your
radio.
E X P L A N A T I O N O F F E A T U R E S : E X P L A N A T I O N O F F E A T U R E S :
E X P L A N A T I O N O F F E A T U R E S : E X P L A N A T I O N O F F E A T U R E S :
1. 4 x 2.5cm analogue meter.
2. Meter Lock / ON
3. SWR Calibration Knob .
4. Meter zero adjustment screw
5. Function switch : RW,SWR / FW,CAL .
6. Function switch : WATT / SWR.
7. Power range switch 12W / 120W.
8. +5-24V DC power for meter illumination.
9. ANT : RF output to an antenna or dummy load .
10. TX : RF power input from a radio .
FORWARD POWER MEASUREMENT
1.Set the function switch 2 to the "ON"
"WATT"
2.Set the function switch 6 to the
3.Set the function switch 5 to the "FW"
4.Set the radio transceiver to transmit and read the
scale corresponding to the Power range selected switch
(12W, or 120W)
REFLECTED POWER MEASUREMENT
1,Set the function switch 2 to the "ON"
2.Set the function switch 6 to the "WATT"
3.Set the function switch 5 to the "RW"
4 Set the radio transceiver to transmit and read the
scale corresponding to the Power range selected switch
(12W, or 120W)
V.S.W.R. & Power Meter Instruction
This S.W.R. & Power meter is a highly accurate RF meter for measuring Forward Power,
Reflected Power, and V.S.W.R.
Main Features:
· LED back light ,analogue meter for easy reading.
· Forward RF power readings .
· Reflected RF power readings.
· V.S.W.R. ratios.
· Convenient control for easy operation.
· None battery read control .
MODEL NO.
Frequency Range
Power Range
S.W.R. Range
V.S.W.R mesure
Led light DC in power
Input/Output Impedance
Input/Output Connectors
Size (include connector)
Weight
Accessories
**All Specifications are subject to change without notice
VSWR MEASUREMENT
Step 1
1. Set the function switch 2 to the
2. Set the function switch 6 to
3. Set the radio transceiver to transmit mode.
4. Slowly turn the CAL control Knob clockwise until the meter point is at the
position. This should be full scale.
Step 2
Set the function switch 5 to the 'SWR' position while transmitting. The meter will now
indicate the SWR ratio.
CAUTION
1.5 -> 2.0. Your antenna is acceptably tuned and should work fine.
2.0 -> 3.0. Your SWR reading is slightly high, it shouldn't damage your radio
but you should try and tune your antenna to bring down your SWR
reading.
Above 3.0 or more . Your antenna isn't tuned acceptably and could damage your
CAUTION
1. Since the meter is very sensitive, avoid excessive vibration or mechanical shock to the unit.
2. The absolute maximumpower that should be applied to the meter is 120W.
3. The transceiver and antenna connections to the meter must never be reversed.Always observe the
correct connections to the transmitter and the antenna .
4. The meter has been carefully calibrated at the factory. Tampering with any of the internal circuitry or
sensors may cause damage and will degrade the accuracy of the meter.
. Do not expose the meter to excessive temperatures, high humidity, or strong magnetic fields.
Understanding S.W.R. Meters
An SWR (Standing Wave Ratio) meter is an instrument used to measure the amount of reflected
power (power coming back from the antenna and/or transmission cable) to the transmitter. For a
transmitter to provide all the power to an antenna, the antenna needs to be resonant and the
transmission cable (coax) has to introduce minimum loss. In a perfect scenario, in an efficient antenna
system, all the power outputted from the transmitter makes it into the atmosphere. Both the coax and
the antenna, if not tuned right will induce losses. These losses will not make it out to the air but come
back to the transmitter in the form of "standing waves".
SWR is the ratio of the forward power vs the reflected power. A perfect antenna system will show
100% forward power and 0% reflected power and is referred to as 1.0:1 which is hard to maintain.
Typically a 1.1:1 is ideal and 1.2:1 is average.
Anything over 3.0:1 is suspect and needs troubleshooting or tuning.
3:1 is unacceptable and could damage the transmitter if it doesn't have reflected power protection
(foldback) circuitry.
a 1.0:1 is 100% efficiency to the atmosphere.
a 1.1:1 is 0.2366% loss, a 1.2:1 is 0.826% loss,
a 1.5:1 is 4% loss, and a 2:1 is 11.1% loss of power.
SW-112 HF SW-112 VU
1.5MHz -60MHz 125MHz-525MHz
0 - 120Watts (Maximum)
1:1~
∞
Power required = > 4 Watt
DC +5V ~12V
50 Ohm
SO-239
88(W) x 59(H) x 80 (D)
270g
Instruction Manual , USB to 5.5/2.1mm cable
"ON"
the"SWR" , .Set the function switch 5 to the
Unfortunately you cannot tell if a problem is in the antenna or
coax (transmission line) if it is placed at the output of the
transmitter shown above.
Placing the SWR meter at the output of the transmitter may
not necessarily show accurate reflected power since losses
in the coax can show up as a decrease in reflected power.
Also if there is high SWR, it can show a high false reading
of output power from the transmitter.
To accurately measure output power of transmitter you
must place the S.W.R. meter between a good 50 ohm
purely resistive "dummy load" and the transmitter as shown
below. Accurately note the power out first. Be aware that
some SWR meters cannot accurately measure power
output. Just relative output for indicating reflected power.
The SWR meter should then be placed between the end of
the coax run with a dummy load as shown below.
"CAL"
"CAL"