3 freq key, 4 avg key, 5 zero/cal key (single key press operation) – Boonton 4240 RF Power Meter User Manual

Page 43: 3 freq key -19, 4 avg key -19, 5 zero/cal key (single key press operation) -19, Boonton 4240 series rf power meter, Getting started 3-19

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Boonton 4240 Series RF Power Meter

3.3.3 FREQ Key.

he fre

T
in

quency of the signal being measured must be entered in order to use the stored high frequency calibration factors. The

Channel 1 is entered by positioning the cursor to the value field under the CH1

eading and pressing the <Enter> key. A value between 0.01 GHz and 100 GHz can be entered. The power on default is 0.05

Hz. Once the frequency is nt red, the corr spondin Ca Factor is di l

d i dB be at h fre ue cy.


strument will then compute, display and apply the required correction factor to subsequent measurements.


The operating frequency may be set by first pressing the <FREQ> key. The instrument will advance to the Frequency menu as

hown in Figure 3-20. The frequency for

s
h
G

e e

e

g

l

sp aye n

ne h t e q n

F

R

E

Q U

E N C Y

C

C

H 1

H 2

G H z

> 0 1 8

.

0 0 0 2 . 5 0

0

d B C F

0 . 0 2

0 0 0

. 1 0 - 0

Figure 3-20. Frequency Display

he averaging time may be adjusted to optimize measurement speed and display stability. Averaging time, in seconds, can be

T I M E


3.3.4 AVG Key.

T
adjusted in 0.05 increments to a maximum of 20.00 seconds. The length of the filter in number of samples is shown on the
display.

To adjust the averaging time, press the <AVG> key and the instrument will display the screen as shown in Figure 3-21.
Position the cursor under the desired channel heading and press the <Enter> key. Use the arrow keys to set the desired value
and then press <Enter> to accept. Entering 00.00 selects the auto filtering Mode. This menu can be accessed to show the filter
setting in the auto mode.

C H 1 C H 2

S E C

> 1 0 . 5 0

0 0 . 0 8

S A M P S

2 1 0

1 6

Figure 3-21. Averaging Time Display

3.3.5 Zero/Cal Key (single key press operation).

Zeroing should be performed when the unit is first warmed-up, a sensor has been changed or the instrument has drifted a

ng is performed, the instrument calculates and stores zero

rrections for each range, and applies the corrections to subsequent measurements.


Assigning the <Zero/Cal> y as a

op at n allo s for a f st zero

th

e hardware range to avoid

the longer zeroing pr es

When he

e

h

s measuri l e

p x a

0 dBm, and if the

measurement is settled hat is, if th il

is ll

e

g e

e

C > y will take

rement as the zero

reference. This allow

r

ter an

o

m s

m ts of w v

i

l

rement is not settled the

complete zeroing process

ll

g is e

m .

significant amount with respect to the signal level being measured. For large signals (measurements taken on range 4, 5, or 6),
this may be done once every several hours. For small signals, (measurements taken on range 0, 1, 2, or 3), zeroing should be
done before each measurement for optimum results. When zeroi
co

ke

s.

sing

t

le key press

C

er io

i

w

a

ing

elow

of

ap

e low

ro

st

tely

oc

Activ

annel

ng ev ls b

im

-5

, t

e f ter fu , pr ssin th <Z ro/ al ke

the displayed measu

s fo fas

of a

d m

es

re

p

actu
rfor

rate

ed

ea ure en

lo le el s gna s. If the measu

ran

Getting Started

3-19

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