PRAXSYM t-meter, User Manual

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BROADBAND WIRELESS POWER METER
Measuring Transmitter Power
The meter should be connected to the transmitter according to the
“FORWARD SIGNAL” label on the meter (see the illustration on the
opposite page). Depending on the gender of the type “N” connector
on the transmitter it may be necessary to use the double male type
“N” adapter. The meter should be terminated with the 50
Ω load in-
cluded in the kit.
Turn the unit on by pressing the ON-OFF button. Select the fre-
quency band of interest by pressing the MODE button until the fre-
quency list is shown. Use the SELECT button to scroll through, and
select the appropriate band. A small arrow will be displayed beside
the band.
Press the FWD button to read the forward power. A small right-
pointing arrow will appear in the upper right side of the display. This
is the amplitude of the signal (in dBm or mW, depending on the unit
selected in the MODE menu) in the forward direction.
The meter is designed to detect signals between 0 and 20 dBm in the
forward direction, and -20 to 17 dBm in the reflected. Damage can
occur to the meter if the forward power into the meter (without the
attenuator) exceeds 33 dBm.
Most broadband radio transmitters deliver less than 100 mW (20
dBm). The 2 W 10 dB attenuator can be used for sources that are
between 20 and 30 dBm in amplitude. Remember to apply the ap-
propriate offset in the MODE setting (“10 attn” if the attenuator in-
cluded in the kit is used). If the output of the transmitter exceeds 33
dBm (2 W), an attenuator of the appropriate power rating and inser-
tion loss should be used to lower the signal to a level below 20 dBm.
Using the MODE button an offset can be configured for attenuators
up to 30 dB. If an attenuator is not used, the offset should be set to
“00 attn”.
While the forward power is displayed constantly on the top line of
the display, the bottom line alternates between the VSWR and the
frequency band and offset settings.
NOTE: A good way to verify proper operation of the 50 Ω termination
(included in the kit) is to make sure that a VSWR of 1.3:1 is displayed
when the meter is connected according to the diagram on the oppo-
site page. If the VSWR is not 1.3:1 the termination should be re-
placed.
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