B+K precision 2650 User manual

Instruction Manual
Model 2650 3.3GHz Spectrum Analyzer

2650 Instruction Manual Rev.1.a 2of60
General Safety Information
This portion provides general information for your safety. Before using this unit, please read all
Warning notes on the back of the unit
•This Instrument must be used only by qualified personal that are aware of the risks of
exposure to electric shock while performing electrical measurements on open circuits.
•Never use unit under severe whether conditions especially thunder storms.
•Never work in extremely close proximity from Hi-Power transmitting antennas without taking
proper safety precautions listed by FCC.
•Always ground the unit to insure static electricity protection in stationary applications. Not
properly grounded unit can damage tested circuits and in some cases expose user to the
electric shock.
•In the case unit starts producing abnormal sounds, smell or smoke, immediately turn off the
unit, disconnect AC adapter and remove the battery. Contact authorized repair center to
arrange service.
•Any adjustments, calibrations, maintenance or repair work could be performed only by
authorized repair center.
•Never use an AC adapter other than the one specified. Using unspecified adapter might
damage the unit and avoid manufacture warranty.
•Never use a battery other than the one specified, because doing so it might damage the unit
and avoid manufacture warranty. When removing or installing the battery, turn off the unit
and disconnect the AC adapter first.
•For fuse replacement, disconnect the AC adapter first, open the battery compartment and
remove the battery. Fuse located under battery in the battery compartment. Use only 5A/120V
slow-blow fuse. Always use specified fuse. Using unspecified fuse might damage the unit and
avoid manufacture warranty.
Warm-up time
To ensure the 100% specified measurement accuracy the 2650 needs to have at list 10 minutes of
warm-up time, before performing any crucial measurements in the field. Always perform 10 min
warm-up if unit is going to work in any stationary applications.

2650 Instruction Manual Rev.1.a 3of60
Table of Contents:
1. Overview ..............................................................................................................................7
1.1 Product Introduction...................................................................................................7
1.2 Standard accessories....................................................................................................8
1.3 Optional accessories.....................................................................................................8
2Specifications...................................................................................................................9
2.1 Front panel view. .......................................................................................................12
32650 Front Panel at a Glance...................................................................................13
4Description Of Screen.................................................................................................15
5Function Key Menu.....................................................................................................16
5.1 List of the Function key menus.................................................................................16
5.2 Menu tree....................................................................................................................18
6Preparing For Operation...........................................................................................23
6.1 Support stand.............................................................................................................23
6.2 Connection to power supply .....................................................................................23
6.3 Replacing the fuse......................................................................................................24
6.4 Installing the battery .................................................................................................24
6.5 Soft carrying case.......................................................................................................24
7Center Frequency.........................................................................................................25
7.1 Setting with the step keys <F1, F2, F3> ...................................................................25
7.2 Setting with the encoder <Enc ST>..........................................................................25
7.3 Setting with the numeric keys...................................................................................25
7.4 Marker position. ........................................................................................................26
8Frequency Span............................................................................................................26
9Reference Level.............................................................................................................27
9.1 Setting the Reference level........................................................................................27
9.2 Switching units of amplitude axis.............................................................................27
9.3 Reference level setting range for each unit..............................................................27
9.4 Relation between the reference level and ATT, AMP (in dBm indication)..........28
10 Display Scale...............................................................................................................28

2650 Instruction Manual Rev.1.a 4of60
10.1 Setting by using the F1, F2 keys...............................................................................29
10.2 Setting by using the encoder.....................................................................................29
11 Resolution Bandwidth..............................................................................................29
11.1 MANUAL mode.........................................................................................................29
11.2 AUTO mode ...............................................................................................................29
11.3 ALL auto mode ..........................................................................................................29
12 Video Bandwidth <VBW>......................................................................................30
12.1 MANUAL mode ...........................................................................................................30
12.1 AUTO mode ...............................................................................................................30
12.2 ALL auto mode ..........................................................................................................30
13 Sweep Axis ·Detection Mode <SWEEP>........................................................31
13.1 MANUAL mode.........................................................................................................31
13.2 AUTO mode ...............................................................................................................31
13.3 ALL auto mode ..........................................................................................................31
13.4 Setting the Detection mode .......................................................................................31
14 AUTO Tuning <AUTO TUNE>...........................................................................32
15 Hold/Run <HOLD/RUN>.......................................................................................32
16 Calculation Function <CALC>............................................................................32
16.1 NORM mode ..............................................................................................................32
16.2 MAX HOLD mode ....................................................................................................32
16.3 MIN HOLD mode......................................................................................................33
16.4 AVERAGE mode.......................................................................................................33
16.5 OVER WRITE mode ................................................................................................33
17 Marker <MKR>.........................................................................................................33
17.1 Moving the marker....................................................................................................34
17.2 Setting the peak search <PEAK SEARCH>...........................................................34
17.3 Changing marker point reference level <CONV>..................................................34
18 Save/Load <SAVE/LOAD>....................................................................................35
18.1 Setting location for trace storage.............................................................................35
18.2 Setting the location to store the parameter.............................................................35
18.3 Saving the data...........................................................................................................35

2650 Instruction Manual Rev.1.a 5of60
18.4 Loading the data........................................................................................................35
18.5 Clearing the loaded trace..........................................................................................36
18.6 Presetting (Initialization) ..........................................................................................36
19 Measuring Function <MEAS>.............................................................................36
19.1 Channel power measurement <Ch Power> ............................................................37
19.2 Adjacent channel leakage power measurement <Adj Ch Pw> <F2> ...................38
19.3 Occupied frequency bandwidth measurement <Occ BW> <F3> .........................39
19.4 Electric field strength measurement <E/F ANT> <F4>........................................39
19.5 Magnetic field strength measurement <M/F PROBE> (optional) <F5>..............43
20 Screen Control <DSPL>.........................................................................................44
20.1 Adjusting the contrast...............................................................................................44
20.2 Switching ON and OFF the LCD backlight............................................................44
20.3 Adjusting the brightness of the LCD backlight......................................................44
20.4 Inverting the display..................................................................................................44
20.5 Enabling or disabling the beep.................................................................................45
21 Printing <PRINT>....................................................................................................45
21.1 How to connect...........................................................................................................45
21.2 Print screen................................................................................................................45
22 Data Output <RS232C>..........................................................................................45
22.1 Selecting the trace to transfer...................................................................................46
22.2 Selecting the communication speed (baud rate).....................................................46
22.3 Transfer the data <EXEC> ......................................................................................46
23 RS-232C Interface....................................................................................................47
23.1 RS-232C specifications..............................................................................................47
23.2 How to connect...........................................................................................................47
23.3 Command description...............................................................................................47
23.4 Input the frequency...................................................................................................53
23.5 Sample of remote program.......................................................................................53
24 PC Software Model AK 2650.................................................................................53
24.1 Installation/Uninstallation procedure......................................................................53
25 Calibration procedures............................................................................................55

2650 Instruction Manual Rev.1.a 6of60
25.1 Frequency characteristics check..............................................................................55
25.2 Reference level accuracy check................................................................................56
25.3 Center frequency display check...............................................................................56
25.4 The display accuracy of the Frequency span..........................................................57
25.5 Linearity of the amplitude axis ................................................................................57
26 Service Information..................................................................................................58

2650 Instruction Manual Rev.1.a 7of60
1. Overview
1.1 Product Introduction
2650 is ideal hand held spectrum analyzer capable to deliver performance and functions comparable
to bench stationary analyzers.
1. Compact and light
The external dimensions are (W×H×D) 6.4×2.8×10.2” (162×70×260 mm). Weight is 3.7lb. (1.7 kg)
including the battery. That alone make 2650 versatile hand healed unit for field use alone with
stationary applications.
2. Frequency range 50kHz to 3.3GHz
This bandwidth is cover W-CDMA, CDMA, PDC, PHS, GSM, 2.4GHz band wireless LAN,
Bluetooth, etc.
3. Operation time on battery power up to 100 min
2650 will work approximately 100 Min on fully charged battery (with display back light off).
4. Bench type, stationary analyzer capabilities
2650 guarantees a highly stable frequency axis by PLL synthesizer system. Center frequency step
setup resolution is 100kHz. Displayed average noise level -110dBm or less. Turns, a broad dynamic
range is secured and the reference level can be set in 1 dB steps.
5. Functions
•Measuring functions: Channel power measurement, channel leakage measurement, Occupied
frequency bandwidth measurement, Electric field strength measurement, and Magnetic field
strength measurement.
•Electric field strength measurement:
•Optimum for measurement of cellular phone and wireless LAN working environment.
•Magnetic field strength measurement:
•Optimum for EMI design verification and evaluation of printed circuit boards.
•Calculation functions: MAX HOLD, MIN HOLD, AVERAGE, OVER WRITE
•Marker * peak search.
•Save/load
6. Auto tuning
The center frequency is set at the spectrum of the maximum level in the 3.3GHz band, and in
addition, optimum reference level, resolution bandwidth, video bandwidth and sweep time are set
when the AUTO TUNE key is pressed.
7. Auto range
The resolution bandwidth, video bandwidth and sweep time are set automatically based on the
frequency span settings. It is also possible to set auto range motion only one out of resolution
bandwidth, video bandwidth and sweep time.
8. Printing capability
Then PT2650 (optional printer) is connected to the analyzer, user could use print command to get
screen image printout. PT2605 printer operateson both AC adapter and alkaline standard AA batteries.
Battery-powered, printer operates for approximately 30 min (printing time).

2650 Instruction Manual Rev.1.a 8of60
9. Display resolution.
Trace resolution could be as high as 1,001points (in the horizontal axis) then it is displayed on PC
screen by using 2650 optional PC Software.
1.2 Standard accessories
1) AC adaptor BC 2650
2) Soft carrying case
3) Accessory pouch.
4) Fuse (Ithas been installed in the inside)
5) Operating manual
6) Ni-MH Battery BP 2650 (Refer to “6.4 Installing the battery” for details.)
1.3 Optional accessories
1.) Dipole antenna AN 301, AN 302, AN 303, AN 304
(Refer to “19.4 Electric field strength measurement” for details.)
2.) Magnetic field probe PR 26M with adedicated double-shielded coaxialcable.
(Refer to “19.5 Magnetic field strength measurement” for details.)
3.) PC software AK 2650 (Refer to “24. PC Software” for details.)
4.) Printer with AC adaptor. 4pcs of AA batteries, aroll paper.
(Refer to “21. Printing” for details.)
5.) Roll paper for optionalprinter PX 2650 (with 10 rolls)
6.) SMA coaxialcable CC301(50cm), CC302(1m), CC303(1.5m)
Bandwidth is DC to 10GHz (VSWR< 1.5) performance could change by bending and
deteriorate by repeating the insertion and extraction.

2650 Instruction Manual Rev.1.a 9of60
2Specifications
Frequency
Frequency range 50kHz to 3,3GHz
Center frequency
Setting resolution 100kHz (Allows rotary encoder, numeric key and function key)
Accuracy within ± (30+100T) kHz±1dot
T : Sweep time (s) (frequency span : 200kHz to 10MHz, RBW : 30kHz, 23 ±5°C)
within ± (100+700T) kHz±1dot
(frequency span : 20MHz to 3.3GHz, RBW : 100kHz, 23 ±5°C)
RBW frequency error within ± 6% of RBW (RBW : 3kHz, 30kHz)
within ± 30% of RBW (RBW : 100kHz to 3MHz)
Frequency span
Setting range 0Hz (zero span), 200kHz to 2GHz (1-2-5step) and 3.3GHz (full span)
Accuracy within ± 3% ± 20TkHz ± 1dot
(Frequency span: 200kHz to 10MHz, 23 ±5°C)
T: Sweep time (s) within ±3% ±200TkHz ±1dot
(Frequency span : 20MHz to 3.3GHz, 23 ±5°C)
Display resolution Frequency span/250
Frequency span/1000
(only the measurement by RS-232C communication)
Display dot number 251dots, 1001dots
(only the measurement by RS-232C communication)
(The unit displays data in 251 horizontal dots, but it internally
captures the trace in 1001 dots)
Resolution bandwidth 3dB bandwidth
Setting range 3kHz to 3MHz (1-3step) and AUTO
Accuracy within ±20%
Selectivity 1 : 12 (typical, 3dB : 60dB)
Video bandwidth 100Hz to 300Hz (1-3step), OFF and AUTO
SSB Phase noise -90dBc / Hz (typical, 100kHz offset, RBW : 3kHz, VBW : 100Hz,
Sweep time : 0.3s)
Spurious response less than -60dBc
Harmonics less than -40dBc (50kHz to100MHz)
less than -45dBc (100MHz to 3.3GHz)

2650 Instruction Manual Rev.1.a 10of 60
Amplitude
Reference level
Setting range +10 to -40dBm (1dB step)
Accuracy within ±0.8dB ±1dot (center frequency : 100MHz, RBW : 3MHz, VBW
: OFF, ATT : 0dB, 23 ±5°C)
Unit dBm, dBV, dBmV, dBµV, dBµV/m, dBµA/m
(dBµV/m and dBµA/m is used the measuring function)
Average noise level -
110dBm
(typical, center frequency : 100MHz RBW : 3kHz, VBW : 100Hz)
Freq. Characteristic within ±2.0dB ±1dot (50kHz to100MHz)
within ±1.0dB ±1dot (100MHz to 3.3GHz)
Input impedance 50ohm
Input VSWR less than 2.0
Input attenuator
Operating range 0 to 25dB (1dB step), coupled with reference level
Switching error within ±0.6dB
RBW switching error within ±0.6dB
Display resolution 0.4dB (10dB/div), 0.08(2dB/div)
Display dot number 200dot
Display scale 10dB / div, 2dB / div
Scale within ±0.2dB / 2dB ±1dot
Accuracy within ±0.8dB / 10dB ±1dot
within ±1.6dB / 70dB ±1dot
Input damage level +20dBm (CW average power), 25VDC
Input connector SMA (J)
Sweep
Sweep time
Range 10ms to 30s (1-3step, frequency span: 0 to 2GHz) and AUTO
30ms to 30s (1-3step, frequency span: full span) and AUTO
Accuracy within ±0.1% ±1dot (frequency span: 0 to 2GHz)
within ±1.5% ±1dot (frequency span: full span)
Trigger mode AUTO (frequency span : zero span)
Detection mode Positive peak, Negative peak, Sample
(when sweep time is 10ms or 30ms, only Sample can be set)
Functions
Marker NORM: displays frequency (7 digits max) and level (4 digits max) at
marker point.

2650 Instruction Manual Rev.1.a 11of 60
DELTA: displays difference frequency and level between 2 markers.
Peak search NORM: searches a peak point within 10div. Available NEXT peak
(10max).
ZONE: searches a peak point within a zone designated by center and
width. Marker moves to a peak point each sweep.
Calculation NORM, MAX HOLD, MIN HOLD, AVERAGE, OVER WRITE
MAX/MIN HOLD: 2 to 1024 times, AVERAGE: 2 to 256
Measuring Channel power, Adjacent channel power, occupied frequency
bandwidth, Electric field strength (needs optional antenna), Magnetic
field strength (needs optional magnetic field probe) measurement.
AUTO tuning When pressing AUTO TUNE key, the maximum level spectrum within
3.3GHz bandwidth is adjusted to center, and reference level, RBW,
VBW and sweep time are adjusted to optimum values.
Save / Load
SaveSaves 100 traces and 100 setups
Load Loads 1 trace and 1 setup
General
Communication
Interface RS-232C
Baud rate 2,400 to 38,400bps
Hard copy allows direct hard copy with an optional printer
Display
Display LCD
Backlight CFL backlight
Resolution 320 (H) × 240 (V) dots
Power source
Battery Ni-MH Battery (included)
External DC Pin jack, DC5V / 4A (BC 2650 included)
Operating temperature 0 to 40°C (Guaranteed at 23 ±10°C, without soft carrying case)
Operating humidity less than 40°C / 80%RH (Guaranteed at less than 33°C / 70%RH,
without soft carrying case)
Storage temperature -20 to 60°C, less than 60°C / 70%RH
Dimensions (WxHxD) 6.4 x 2.75 x 10.25 (162 × 70 × 260 mm)
Weight (approx.) 3.75 lb. (1.7kg) included battery
3.3 lb (1.5kg) without battery

2650 Instruction Manual Rev.1.a 12of 60
2.1 Front panel view.
BK Precision Corporation reserves the right to make changes in design, specification and other
information without prior notice.

2650 Instruction Manual Rev.1.a 13of 60
32650 Front Panel at a Glance
1) LCD display
High-resolution 320×240 liquid crystal display. It simultaneously displays traces (10×8 div),
various setting values, measured values, etc.
2) Input connector
SMA J type input connector.
3) External powerconnector
Power connector. In use for external BC 2650 AC power adapter.
4) RS-232 connector
RS-232C port.

2650 Instruction Manual Rev.1.a 14of 60
5) Function keys (F1 to F6)
Flexible, function key.
6) Center frequency key
This key is used to set the center frequency. Center frequencycan be set in range from 0 to
3.3GHz (100kHz step).
7) Frequency span key
Use this key to set the frequency span. It can set between 200kHz to 2GHz, ZERO SPAN and
FULL SPAN (3.3GHz).
8) Reference level key
Set the reference level. It can set between +10dBm to -40dBm (1dB step).
9) Resolution bandwidth key
Use this key to set the Resolution bandwidth. It can set between 3kHz to 3MHz.
10) Video bandwidth key
Use this key to set the video bandwidth between 100Hz to 300kHz or OFF.
11) AUTO tuning key
Automatic tunes measured signal spectrum within 3.3GHz bandwidth. This does not operate
normally when the signal level is -40 dBm or lower and the input frequency is 50 MHz or
lower and the frequency span is ZERO SPAN and FULL SPAN.
12) Measuring function key
Available for Channel power, channel leakage, occupied frequency bandwidth, Electric field
strength and Magnetic field strength measurement.
13) Calculation function key
Available for Max hold, Min hold, Average and Over write.
14) Display scale key
Use this key is used to select the display scale of amplitude from 2dB/div or 10dB/div.
15) Sweep key
This key is used to set sweep time between 10ms to 30s or set the detection mode.
16) Hold/Run key
Stops or restarts the measurement.
17) Marker-Peak search key
Use this key to set and move a marker.
18) Save/Load key
Saves 100traces and 100setups, and loads 1trace and 1setup.
19) Print key
Print screen key, if optional printer is connected.
20) RS-323C key
Sets baud rate and transfers a current or saved trace.

2650 Instruction Manual Rev.1.a 15of 60
21) Display control key
Control’s contrast, backlight ON/OFF, brightness of backlight, invert display and buzzer
ON/OFF functions.
22) Rotary encoder
Universal encoder
23) Power switch
Power switch
4Description Of Screen
Trace display
10 Div. X 8 Div.
Display for function keys
Frequency settings display
Center frequency, Frequency span,
Resolution bandwidth, Video bandwidth
Amplitude setting display
Reference level
Input attenuator,
Display scale
Sweep setting display
Sweep time,
Detection mode
Calculation display
Measuring display
Current operation
information display
Loaded trace information display.
Display current settings when the
measuring function is used. Currently measured value

2650 Instruction Manual Rev.1.a 16of 60
5Function Key Menu
5.1 List of the Function key menus
The List of all function keys is shown in the table below. For description of each function, please see
the detailed pages. For the flow of change in the function key display, refer to 5.2 Menu tree.
Function key menus Key flow Detailed page
Adj Ch OFS MEAS>(F6)>(F2)>(F2)>F2 38
Adj. Ch Pw MEAS>(F6)>F2 38
Adj. Ch WIDTH MEAS>(F6)>(F2)>F3 38
ANT MEAS>(F6)>(F5)>F1 39
A)
AVER CALC>F4 32
B.L. (back light) DSPL>F2 44
BACK SPACE FREQ>F5>F6 25
BAND CNTR MEAS>(F6)>(F1)>(F1)>F2 37
BAND WIDTH MEAS>(F6)>(F1)>(F1)>F3 37
BAUD RS232>F2 46
BLCTR (display brightness) DISPL>F3 44
B)
BUZZR (beep sound) DISPL>F5 44
CENTER FREQ <FREQ>F1 25
CENTER FREQ >FREQ>F2 25
Ch. Power MEAS>(F6)>F1 37
CLEAR FREQ>F5>F5 25
CONV MKR>F6 34
C)
CTRS (display contrast) DSPL>F1 44
D) DET (sweep auto detection) SWEEP>F4 31
E/F ANT MEAS>(F6)>(F3)>F4 39
EncST FREQ>F4 25
EXEC RS232>F3 46
EXECUTE DEL SAVE/LOAD>F5 36
EXECUTE LOAD SAVE/LOAD>F4 35
E)
EXECUTE SAVE SAVE/LOAD>F3 35
I) INVT (display inverter) DSPL>F4 44
K) KeyST FREQ>F3 25
M/F PROBE MEAS>(F6)>F5 43
MAXHD CALC>F2 32
MEAS OFF MEAS>(F1~5)>F6 37
MINHD CALC>F3 33
MKR DELTA MKR>F2 34
MKR NORM MKR>F1 34
M)
MODE MEAS>(F6)>(F1~3)>F1 36

2650 Instruction Manual Rev.1.a 17of 60
NORM CALC>F1 32 N) NUM FREQ>F5 25
Occ BW MEAS>(F6)>F3 39 O) OVPWR CALC>F5 33
PARM (location) SAVE/LOAD>F2 35
PEAK SEARCH CNTR MKR>(F3)>F4 34
PEAK SEARCH NEXT MKR>(F3)>F5 34
PEAK SEARCH NORM MKR>(F3)>F3 34
PEAK SEARCH PEAK MKR>(F3)>F4 34
PEAK SEARCH WIDTH MKR>(F3)>F5 34
PEAK SEARCH ZONE MKR>(F3)>F3 34
PRE SET SAVE/LOAD>F6 36
P)
PROBE MEAS>(F6)>(F5)>F1 43
RATIO MEAS>(F6)>(F3)>F2 39
RBW ALL RBW>F3 29
RBW AUTO RBW>F2 29
RBW MANU RBW>F1 29
PREFERENCE CNTR MEAS>(F6)>(F2)>F4 38
R)
PREFERENCE WIDTH MEAS>(F6)>(F2)>F5 38
SCALE 10dB SCALE>F1 29
SCALE 2dB SCALE>F2 29
SET MKR FREQ>F6 26
SWEEP ALL SWEEP>F3 31
SWEEP AUTO SWEEP>F2 31
S)
SWEEP MANU SWEEP>F1 31
TRACE SAVE/LOAD>F1 35 T) TRACE RS232C>F1 46
UNIT dBm REFER>F1 27
UNIT dBmV REFER>F3 27
UNIT dBV REFER>F4 27
U)
UNIT dBµV REFER>F2 27
VBW ALL
VBW>F3 30
VBW AUTO
VBW>F2 30
V)
VBW MANU
VBW>F1 30

2650 Instruction Manual Rev.1.a 18of 60
5.2 Menu tree
Icons displayed on the bottom of the screen correspond to the function keys under them, as shown in
the figure below:
Ch Adj Occ E/F M/F
Power Ch Pw BW ANT PROBE
CENTER FREQ KeyST EncST SET
<>100M 0.1M NUM MKR
Back
Clear Space
UNIT
dBm dB µV dB mV dBV
FREQ
F2
F3
F4
F5
F6
Refer to “7. Center Frequency”for details
F1
REFER Refer to “9. Reference Level”for details
Use encoder to set Center frequency
Use encoder to set Reference level

2650 Instruction Manual Rev.1.a 19of 60
RBW
MANU AUTO ALL
VBW
MANU AUTO ALL
Ch Adj Occ E/F M/F
Power Ch Pw BW ANT PROBE
MODE BAND MEAS
BAND CNTR WIDTH OFF
RBW
VBW
MEAS
Refer to “11. Resolution Bandwidth”fordetails
Refer to “12. Video Bandwidth”for details
Refer to “19. Measuring Function”for details
Use encoder to set RBW
Use encoder to set VBW
Use encoder to set parameter
Use encoder to set parameter

2650 Instruction Manual Rev.1.a 20of 60
MODE Adj Ch Pw REFERENCE MEAS
TOTAL OFS WIDTH CNTR WIDTH OFF
MODE RATIO MEAS
N% 99.9% OFF
ANT MEAS
M301 OFF
Ch Adj Occ E/F M/F
Power Ch Pw BW ANT PROBE
PROBE MEAS
CP-2S OFF
NORM MAX HD MIN HD AVER OVRWR
* * * * 256
CALC
Input the probe ID (first time only)
Refer to “16. Calculation Function”fordetails.
Use encoder to s
et parameter
MEAS
Use encoder to set parameter