Anritsu S251C User Manual

MAINTENANCE MANUAL

Site Master™ Model S251C

Antenna and Cable Analyzer

Figure 1. Site Master Model S251C

1. INTRODUCTION

This manual provides maintenance instructions for
the Site Master S251C Antenna and Cable Analyzer.
It describes the product and provides performance
verification procedures, parts replacement proce

-

dures, and a replaceable parts list.

2. DESCRIPTION

The Site Master (Figure 1) is a hand held S
mission gain or loss), SWR/RL (standing wave ra

21

(trans

­tio/return loss), and Distance-To-Fault measurement
instrument. It combines a synthesized source, VSWR
Bridge, and receiver on a single printed circuit board
(PCB). An optional power monitor is also available. A
block diagram is shown in Figure 2.

3. PERFORMANCE VERIFICATION

Paragraphs 4 through 10 contain tests that can be
used to verify the performance of the Site Master
model S251C having any version of firmware.

3.1. Initial Setup for Testing

1. Press and hold the
press the

-

ter. (This sets the instrument to the factory

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

preset state.)

2. If necessary, use the Up/Down arrow key to
adjust the contrast to give a readable display.
Press

ENTER to accept.

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490 JARVIS DRIVE ¨ MORGAN HILL, CA 95037-2809

P/N: 10580-00067

REVISION B

PRINTED: FEBRUARY 2003

COPYRIGHT 2001-2003 ANRITSU CO.

R F

S o u r c e

C o u p l e r

R F O u t

P o r t

R F I n

P o r t

I n c i d e n t

L o c a l

O s c i l l a t o r

D i s p l a y

Figure 2. Site Master Block Diagram

4. FREQUENCY ACCURACY

The following test can be used to verify the CW fre­quency accuracy of the Site Master. Measurement
calibration of the Site Master is not required for this
test.

a. Equipment Required:

·

Spectrum Analyzer

Anritsu Model MS2668C or equivalent

b. Procedure:

1. Press and hold the
press the

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

ter. (This sets the instrument to the factory
preset state.)

NOTE

Before continuing, allow a five minute
warm up for the internal circuitry to
stabilize.

2. Press the

3. Use the Up/Down Arrow key to highlight

SOURCE

4. Press the

MODE key.

RF

, then press ENTER.

FREQ soft key.

R e f l e c t e d

S y n c h r o n o u s

D e t e c t o r

A / D C o n v e r t e r

C P U

T r a n s m i t t e d

S e r i a l

P o r t

5. Using the keypad or Up/Down Arrow key en­ter 1000.0 MHz then press the

ENTER key.

6. Connect the RF cable from the Site Master
RF Out Test Port to the RF Input on the Spec­trum Analyzer.

7. Set up the Spectrum Analyzer as follows:
(a) Press

Preset

(b) Press the PRESET ALL soft key
(c) Press
(d) Press

-

(e) Press

Frequency and enter 1 GHz
Span and enter 200 kHz
Amplitude

(f) Press the REFERENCE LEVEL soft key and

enter 10 dB

8. If the Site Master has gone into the hold
mode, press the

RUN/HOLD key to make the

measurement.

9. On the Spectrum Analyzer:
(a) Press

Marker

(b) Press PEAK SEARCH. The frequency

should be 1000 MHz ±75 kHz.

2 Site Master S251C MM

5. TRANSMISSION/ISOLATION
VERIFICATION

The following test can be used to verify transmission
test port isolation and the accuracy of transmission
measurements. Measurement calibration of the Site
Master is required for this test.

TransTest Port

TestPort
Extension Cable

Refl Test Port

a. Equipment Required:

10 dB Attenuator, Weinshel 1-10

·

30 dB Attenuator, Weinshel 1-30

·

Open/Short, Anritsu 22NF50

·

50 Ohm Terminations,

·

Anritsu SM/PL or 28N50-2
Anritsu SM/PLNF or 28NF50-2

Armored Test Port Extension Cable,

·

1.5 Meter, N(m) to N(m),
Anritsu 15NN50-1.5A

b. Procedure:

1. Press and hold the
press the

ON/OFF key to turn on the Site Mas-

ESCAPE/CLEAR key, then

ter. (This sets the instrument to the factory
preset state.)

NOTE

Before continuing, allow a five minute
warm up for the internal circuitry to
stabilize.

2. Press the

MODE key.

3. Use the Up/Down Arrow key to highlight

SERTION LOSS

4. Press the

5. Press the

, then press ENTER.

AMPLITUDE key.
TOP soft key.

6. On the keypad, press “0”, then press
(Verify the bottom limit is set to –120 dB.)

7. Press the

LIMIT key.

IN

ENTER.

Site Master S251C

MODE

FREQ/DIST

SWEEP

AMPLITUDE

Figure 3. OSL-THRU-ISOL Calibration Setup

12. Connect a Load (28N50-2 or SM/PL) to the
RF In Test Port and verify that the noise floor
(isolation) is below –80 dB.

13. Press the

14. Press the

MARKER key.
M1 soft key, then the EDIT soft key.

15. Using the keypad or the Up/Down Arrow key,
enter 1000.0 MHz, and press

NOTE

For the following steps in the procedure,
use only attenuators that have Type N
connectors. The use of attenuators with
other type connectors and adapters will
cause measurement errors.

16. Connect the 10 dB attenuator to the RF In

-

Test Port (refer to Figure 4) and verify that
the reading is –10 dB ±2.25 dB @ 1000 MHz.

17. Connect the 10 dB and 30 dB attenuators in
series to the RF In Test Port and verify that
the reading is –40 dB ±3.25 dB @ 1000 MHz.

Attenuator

ESCAPE
CLEAR

2

1

START

AUTO

CAL

SCALE

3

4

SAVE

RECALL

SETUP

SETUP

6

5

LIMIT

MARKER

ENTER

8

7

RECALL

RUN

SAVE

DISPLAY

DISPLAY

HOLD

+

9

0

-

/

PRINT

ON

SYS

OFF

.

ENTER.

TestPort
Extension Cable

8. Press the

9. Press the
the

10. Press the

11. Follow the instructions on the display to per
form a OSL-THRU-ISOL calibration using a
22NF50 Open/Short, 28NF50-2 or SM/PLNF
Terminations, and 15NN50-1.5ATest Port Ex
tension Cable (refer to Figure 3).

SINGLE LIMIT soft key.
EDIT soft key, enter –80, and press

ENTER key.

START CAL key.

-

-

Figure 4. Test Setup

TransTest Port

Refl Test Port

Site Master S251C

MODE

FREQ/DIST

AMPLITUDE

SWEEP

ESCAPE
CLEAR

2

1

START

AUTO

CAL

SCALE

3

4

SAVE

RECALL

SETUP

SETUP

6

5

LIMIT

MARKER

ENTER

8

7

RECALL

RUN

SAVE

DISPLAY

DISPLAY

HOLD

+

9

0

-

/

PRINT

ON

SYS

OFF

.

Site Master S251C MM 3

6. RETURN LOSS VERIFICATION

The following test can be used to verify the accuracy
of return loss measurements. Measurement calibra
tion of the Site Master is required for this test.

a. Equipment Required:

5. Follow the instructions on the screen to per

-

form a calibration using a 22N50 Open/Short

-

and 28N50-2 or SM/PL Termination.

6. Connect the 20 dB offset to the RF Out Test
Port and verify that the reading is 20 dB
±1.7 dB

20 dB offset, Anritsu SC5270

·

6 dB offset, Anritsu SC5237

·

Open/Short, Anritsu 22N50

·

50 Ohm Termination,

·

Anritsu 28N50-2 or SM/PL

b. Procedure:

1. Press and hold the
press the

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

ter. (This sets the instrument to the factory
preset state.)

NOTE

Before continuing, allow a five minute
warm up for the internal circuitry to
stabilize

2. Press the

MODE key.

3. Use the Up/Down Arrow key to highlight

TURN LOSS

4. Press the

, then press ENTER.

START CAL key.

RE-

7. Connect the 6 dB offset to the RF Out Test
Port and verify that the reading is 6 dB
±1.2 dB

7. POWER MONITOR VERIFICATION

If the Power Monitor (Option 5) is installed in the
Site Master, the following test can be used to verify
the accuracy of the power measurements. Measure
ment calibration of the Site Master is not required
for this test.

-

a. Equipment Required:

RF Detector, 10 MHz to 20 GHz,

·

Anritsu 560-7N50B

· 10 dB Attenuator, Weinschel 1-10

· 30 dB Attenuator, Weinschel 1-30

· RF Reference Source, 0.050 GHz,

Anritsu MA2418A

· DC Power Supply, Anritsu 2000-933

-

Attenuators

560-7N50B

RF Detector

MA2418AReference Source

W

50MHz, 50
0dBm

Site Master S251C

MODE

FREQ/DIST

AMPLITUDE

SWEEP

ESCAPE
CLEAR

2

1

START

AUTO

CAL

SCALE

3

4

SAVE

RECALL

SETUP

SETUP

6

5

LIMIT

MARKER

ENTER

8

7

RECALL

RUN

SAVE

DISPLAY

DISPLAY

HOLD

+

9

0

-

/

PRINT

ON

SYS

OFF

.

DC Power Supply 2000-933

20mA

15-24VDC

MA2418A
Reference Source

Site Master w/ Option 5 Installed

Figure 5. Power Monitor Verification

4 Site Master S251C MM

b. Procedure

1. Connect the DC power supply to the
MA2418A Reference Source. (Refer to Figure

5.)

2. Connect the MA2418A Reference Source to
the input of the 560-7N50B RF detector.

3. Connect the RF Detector output to the RF De
tector input of the Site Master.

(Option 10A only works with the AC-DC
Adapter).

2. Apply AC power to the power supply.

3. Press and hold the
press the

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

-

ter. (This sets the instrument to the factory

-

preset state.)

4. Press the

SYS key.

4. Connect the DC power supply to the appropri
ate line voltage to supply power to the
MA2418A Reference Source.

5. Press and hold the
press the

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

ter. (This sets the instrument to the factory
preset state.)

6. Press the

MODE key.

7. Use the Up/Down Arrow key to highlight

POWER MONITOR, then press ENTER.

8. Press the

ZERO soft key to zero the power

monitor.
When complete,

ZERO ADJ:ON is displayed in

the message area.

9. Verify that the power monitor reading is

0.0 dBm ±1 dB.

10. Connect the output of the MA2418A Refer­ence Source to the two attenuators so as to
add 40 dB of attenuation (Figure 5).

11. Connect the MA2418A Reference Source and
the attenuators to the input of the 560-7N50B
RF detector.

-

5. Press the

6. Press the

OPTIONS soft key.
BIAS-T soft key to activate the Bias

Tee option.

-

7. Verify that the display shows

15.0V, 0 mA.

8. Connect the 22NF50 short to the RF In test
port.

9. Verify the test port voltage relay clicks on and
off, and

FAULT is shown in the upper left cor

ner of the display.

10. Remove the short and install the 100 Ohm
load.

CAUTION

The 100 Ohm resistor will get hot. Ver­ify the readings and remove the 100
Ohm load immediately.

11. Verify that the display shows

BIAS, with a

reading of 14.8 to 15.3 Volts, and 120 to 160
milliamps.

9. BIAS T (OPTION 10B) VERIFICATION
a. Equipment Required:

-

·

12. Verify that the power monitor reading is now
–40.0 dBm ±2 dB.

8. BIAS T (OPTION 10A) VERIFICATION
a. Equipment Required:

·

AC-DC Adapter Power Supply 40-115

·

Open/Short, Anritsu 22N50

·

100 Ohm, 1 Watt load (100 Ohm, 1 Watt re
sistor soldered from the center pin to ground
of an N-type connector.)

b. Procedure:

1. Connect the AC-DC Adapter Power Supply to
the battery charging port on the Site Master

-

Open/Short, Anritsu 22N50

·

100 Ohm, 1 Watt load (100 Ohm, 1 watt resis
tor soldered from the center pin to ground of
a N-type connector)

·

Anritsu T2904

b. Procedure:

1. Ensure the battery is fully charged. (Option
10B only works with the battery).

2. Press and hold the
press the

ON/OFF key to turn on the Site Mas

ESCAPE/CLEAR key, then

ter. (This sets the instrument to the factory
preset state.)

3. Press the

4. Press the

SYS key.
OPTIONS soft key.

Site Master S251C MM 5

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