MODEL PA2500 INSTRUCTIONS & SPECS
SOFTWARE VER. 3.1
HARDWARE REV B,C,D,E
COPYRIGHT 1997 DKD INST.
ALL RIGHTS RESERVED
Rev. Date: Mar. 1997
Published by;
DKD INSTRUMENTS
750 Amber Way
Nipomo, Calif. 93444
PH. . (805)929-2285 FAX (805)929-5983
INTERNET E-MAIL ADDRESS:
WEB PAGE
COPYRIGHT NOTICE
This software and document are copyrighted 1997 by DKD Instruments. No part of this publication may reproduced or transmitted in any form or by any means without the prior written permission of:
DKD INSTRUMENTS
750 Amber Way
Nipomo, Calif. 93444
PH. . (805)929-2285 FAX (805)929-5983
INTERNET E-MAIL ADDRESS:
WEB PAGE
DISCLAIMER
The authors have taken due care in preparing this document and software on disk accompanying this document, including research, development and testing to ascertain their effectiveness. The authors and publisher make no express or implied warranty of any kind with regard to these programs nor the documentation in this book. Neither the authors nor DKD Instruments will be liable for incidental or consequential damages in connection with or arising out of the furnishing, performance or use of any of these programs.
SINGLE COMPUTER LICENSE
The price paid for a single copy of PA2500 system software entitles the owner to use the program on a single machine. The owner may remove it and use it on another machine, but at no time is allowed to make multiple copies available for others to use.
TRADEMARKS
Borland, Turbo C are registered trademarks of Borland
International.
QUICK START INSTRUCTIONS
FROM WINDOWS;
1) EXIT WINDOWS
2) C:.>MD PA2500
3) C:>CD PA2500
4) C:>/PA2500>COPY A:*.*
TO START PROGRAM FROM WINDOWS:
1) START FILE MANAGER
2) GO TO PA2500 DIRECTORY
3) DOUBLE CLICK ON PA2500.EXE
FROM DOS:
1) C:> CD PA2500
2) C:> /PA2500> PA2500
OPERATING INSTRUCTIONS FOR MODEL PA2500 SPECTRUM ANALYZER
(VER. 3.1)
ALL USERS
Immediately upon receipt of your system make a copy of the system disk provided with your hardware and put it in a safe place. Each system has custom cut calibration files. DKD Instruments keeps all data files on archive but you should also safeguard your original disk files.
SYSTEM REQUIREMENTS
A 1.44 MB floppy, VGA monitor,1MB Ram as a minimum. Loading and Executing from a hard drive is preferred for speed and a 486 @ 25MHz or better processor. Lower grade processors can be used with degradation in speed of execution.
HARD DRIVE USERS
Hard drive users can simply create a directory for the PA2500 files or use an existing directory. Copy all files from the 1.44 MB diskette into the directory you choose to operate out of. You can now proceed, type PA2500 to start program.
FLOPPY DRIVE USERS
The 1.44 MB floppy provided with unit has all files needed and can be used
immediately, Type PA2500 to execute the user program.
GETTING STARTED
Before using the PA2500 with a PC host computer you must tell the software which interface and what printer you are going to use in your system. From the main menu select STATE . The STATE menus first entry is SETUP. Select SETUP . The SETUP menu should now appear. First check the current configuration of the software. The configuration information consists of card interface, buss address, port selection and printer type/port . The card interface and bus address are for non parallel port operation and are not of concern for almost all users. Select parallel port you will be using and save your selection. You must operate the PA2500 from one of the parallel ports listed.
Printer Interface Selection;
SETUP can be used to select the parallel port used for the printer, LPT1,LPT2 & LPT3. Select as appropriate.
Printer Selection;
This is where you select the printer that will be used for screen dumps. From SETUP select the SELECT PRINTER menu item. A list of printers will appear with a highlight bar at the top of the list. Move the highlight bar to your printer and select it by using F1 function key. If your printer does not appear on the list contact DKD Inst.
CONNECTING UP THE PA2500
After you have used SETUP to configure the software for your system you are ready to connect up and start using your PA2500. Connect the parallel port to your computer using the supplied DB25 cable. You are now ready to connect the power. The PA2500 is powered from a AC type wall adapter. Plug the adapter into a 115 VAC wall outlet . The plug end of the AC adapter is connected at the rear of the instrument. The PA2500 is now ready for use. During normal operation the Interface LED on the front panel will flicker(mostly in off state), this is normal and indicates proper operation.
BATTERY CHARGING (optional)
The PA2500 has an internal battery option that allows for cord free operation. To start a charge cycle turn the front panel power switch OFF and remove the AC power plug. Now cycle the power switch on/off with about a two second hold in the ON position. With front panel switch off plug in the AC adapter plug. This resets the charger and starts a full charge current cycle. When the green Charger led is on the battery is charged. During operation if the Red low battery led comes on you are at the point where the battery must be recharged.
FRONT PANEL
RF IN JACK
N type connector. Signal input point for RF signals between +30dBm and -135dBm. Anytime signal strength is above 0 dBm caution is urged as the potential is there to damage the intrenal preamp, if on. The internal attenuators are rated to 1 watt(+30 dBm). The front panel is labeled “+15dBm MAX” to encourage users to stay below this level. Experienced users who are confident of there max power levels and have correctly setup internal attenuation/preamp can apply full power rating (+30dBm)to instrument although this should be done for short periods only.
POWER SWITCH
Controls internal power to instrument. For units equipped with internal battery option the charger will still be active when this switch is in the off state.
INTERFACE LED
Monitors PC to PA2500 communications. If this LED does not blink a little during operation or is on at all times during operation a problem has occurred with the interface to host PC. See Cal/Diagnostics.
BATTERY STATUS LEDS
On internal battery units these two leds indicate status of charger and battery. See Battery Charging above.
REAR PANEL
CAL OUT
Internal 10Mhz signal source that is attenuated for direct input into spectrum analyzer. This signal is used for self test purposes, See CAL MENU.
EXTERNAL CLOCK JACK
This input allows the use of an external 10MHz , TTL Level, Reference. The reference select switches are located on the rear of the instrument. Both dip switches should be in “ON” state for normal internal reference operation. For external operation switch 1 should “ON” switch 2 should be “OFF”.
AUDIO OUT
Audio Out is a mid level audio signal from the FM demodulator(s). It can be monitored with headphones or external audio amp .
HIDDEN CONTROL CHARACTERS
From the sweep mode there are a number of control characters that that are not displayed for this version of software. DO NOT USE "ALT x" where "x " is any letter. These commands are for calibration purposes only and their improper use can result in loss of calibration data.
PA2500 ACCEPTANCE TEST
THESE TESTS SHOULD BE PERFORMED IMMEDIATELY UPON RECEIPT OF INSTRUMENT. AT THIS TIME THESE TESTS MUST BE SETUP BY USER. FUTURE SOFTWARE RELEASES WILL AUTOMATE MUCH OF THIS PROCEDURE.
1) INSTALL SOFTWARE AND MAKE COPY OF DISK.
2) CONNECT PARALLEL CABLE FROM COMPUTER TO PA2500
3) CONNECT AC ADAPTER TO PA2500 REAR PANEL JACK
4) RUN PA2500 SOFTWARE.
5) GO TO SETUP MENU AND SELECT PROPER PARALLEL PORT TO BE USED BY PA2500.
6) LET UNIT WARM UP FOR 15 TO 20 MINUTES.
CALIBRATION SIGNAL TESTS USING "CAL OUT" SIGNAL;
1) CONNECT THE "CAL OUT " SIGNAL FROM REAR PANEL BNC/TNC TO INPUT "N" TYPE CONNECTOR OF THE PA2500. USE THE SUPPLIED TEST CABLE FOR THIS PURPOSE.
2) RECALL STATE 1
3) TAKE A FEW SWEEPS
4) COMPARE ON SCREEN PLOT WITH CORRESPONDING "CAL OUT" PLOT AS SUPPLIED IN CAL SPECTRUM MEMORIES. USE OF SPECTRUM SUBTRACT SIMPLIFIES THE COMPARE PROCESS. DIFFERENCE SHOULD RESULT IN VERY LOW SPECTRAL COMPONENTS.
5) REPEAT FOR NEXT STATE 2. DO ALL TO STATE 6.
IF THE ON SCREEN POWER LEVEL AND OVERALL SHAPE OF THE PLOTS IS NOT WITHIN +/- 2 DB OF "CAL OUT" SPECTRUMS THEN THERE IS A PROBLEM. IN THIS CASE THE UNIT HAS FAILED THE ACCEPTANCE TEST AND USER SHOULD CONTACT FACTORY.
OPERATION MENUS
MENU ITEM SELECTION
All menu items are selected by using the up/dn arrow keys. Once you are on the menu item hit <CR> to activate the current selection.
MAIN MENU
The Main menu is comprised of the following sub menus; Frequency, Amplitude, Trace, State, Cal/Diagnostic, Program Menu and the return to DOS menu item.
HOT KEYS
The most frequently used menus can be called up using function keys. The key assignment is shown at the bottom of the display.
FREQUENCY MENU
START FREQUENCY:
When selected a highlighted bar will appear with the current start frequency displayed. If a new start freq is desired simply type it in. Use the R/L arrow keys to move cursor to retype over errors. A decimal point is not mandatory. The start frequency has the following limits;
Highband minimum = 1180 Mhz
Lowband minimum = 0 Mhz
Start frequency cannot be chosen independently of center frequency. In addition the transition between HIGH and LOW bands will be done when START FREQ>1180 MHZ. At this time sweeping through 1180 MHZ is not permited.
CENTER FREQUENCY:
As with start frequency a highlighted bar appears showing present center frequency and allowing entry of new center freq. The limits for start frequency also apply for center frequency with the frequency span taken into account. Note: You may exceed the max frequency with either
erroneous start or center commands. The result will be a portion of the display that goes "dead". This is the LO reaching the end of its range. As with start frequency the center frequency cannot be independently specified w.r.t start frequency.
SPAN/RBW/VBW
Span, RBW and VBW are tied together and cannot be independently specified. Therefore choosing a Span automatically specifies RBW and VBW. It is possible to modify the SPAN/RBW/VBW table and within limits SPAN vs RBW/VBW is programmable, SEE PA2500 MATRIX FILE.
SIGNAL TRACK
Signal track finds the peak displayed signal and commands this as center frequency.
SWEEP DELAY
Since system is not calibrated in sweep time user must select sweep delay. This controls amount of delay between each measurement point, see Trace menu.
FAST SWEEP
See Trace menu.
ZERO SPAN
All internal Oscillators are fixed at values such that center frequency is received. The sweep is now a amplitude vs time. Sweep Delay along with processor speed will affect time scale on horizontal axis.
SPLIT SPAN
Not installed at this time.
SELECT VBW
Manual selection of video bandwidth. This overrides selection made automatically in SPAN entry.
NEXT HARMONIC
Every time this button is pressed center frequency is changed to Nth harmonic of starting center. Starting center and N are reset when either Start or Center frequency are re-enetered.
FREQUENCY OFFSET
Used to enter a constant frequency offset on display. Usefull when block down converting a range of frequencies into PA2500’s range.
AMPLITUDE MENU
REFERENCE LEVEL
Reference level determines the power level at the top line of the display grid. Units are in dBm. After selecting with <CR> enter desired reference level in dBm. To get a feel for this its best to try some numbers for reference level, attenuation and dB/DIV to see how they interact.
INTERNAL ATTENUATION
Internal attenuation of 0, 10, 20, 30, 40 and 50 dB is provided with the Internal Step Attenuator option. Be aware that that unless you have a complete attenuator(20 is min.) not all values are valid. Use the UP/DOWN arrow keys to scroll to the attenuation level desired and hit<CR>. See Reference Level for interaction of power readings and attenuation settings.
USER ATTENUATION
This is attenuation that is connected to the PA2500 consisting of pads or step attenuator settings. If you wish to have the PA2500 automatically calculate in the effects of external attenuation use this feature. The entered units are dB. See Reference Level for interaction of User Attenuation with power
readings.
DB/DIV
This selects the dB per division of display grid. Five values are supported, 15, 10, 5, 2, and 1 dB/div. Use the UP/DOWN arrow keys to select the desired value and then hit <CR>.
ATTEN/AUTO MAN
Allows user to select control of internal attenuators. With AUTO mode selected the internal attenuator will automatically switched for reference levels above -40dBm preamp on, -20dBm preamp off.
FM DEMOD
Brings up FM demod menu. See FM DEMOD MENU.
PREAMP ON/OFF
Controls preamp and preamp relay (optional). All units are equipped with a preamp as standard equipment. The preamp relay option allows user to bypass preamp. The advantage of bypassing the preamp is better 3 order intercept point. The disadvantage is reduced sensitivity. For large signals (above approx -40 dBm ) the preamp is not needed as the user will be attenuating the signal.
THRESHOLD
Threshold sets the level at which the FAST SWEEP function slows down and
starts taking measurements at the rate selected by SWEEP RATE. Numbers should be
between 0 and 255. Generally values between 40 and 100 are used. See USING FAST
SWEEP for more information.
TRACE MENU
SWEEP DELAY (See USING FAST SWEEP also)
Sweep Rate is used to change how fast the display is updated. Because of the large variations of clock speeds in the PC world this parameter is used to slow down the faster machines so that they are calibrated in power. Typically for the narrower RBW/VBW combinations delay is equal to 5, for wider combinations it approaches 0. So now select the sweep rate by scrolling through using the UP/DOWN arrow keys and hit <CR> . For 486 100Mhz or better machines LARGER sweep delays will have to be used to insure no amplitude roll off due to settling time of video filter.
SIGNAL TRACK
Positions highest signal at center of sweep.
OVERLAY ON/OFF
Stops current trace from being overwritten on start of next sweep. This trace will be held until overlay is turned off.
FAST SWEEP
The FAST SWEEP function allows the PA2500 increase its sweep speed by using a threshold crossing technique. In the normal mode the SWEEP DELAY sets the delay value used between EACH measurement. In FAST SWEEP this delay is only used IF the power level exceeds THRESHOLD. The threshold is set via the THRESHOLD entry from the SET UP MENU. The threshold is normally set between 20 and 100. The limits of allowed threshold values are 0 to 255. There are no units here as the threshold is compared with raw data (unscaled) from the A to D converter (U12). The wider RBW's will require higher Thresholds as the noise floor will rise.
MAX HOLD
Max hold keeps the current maximum at each measurement point without rewriting the display.
TITLE
Not Installed.
SCREEN DUMP
Screen dump to Printer.
AVG/SPEC
Not Installed
ANALYSIS MENU
MARKER MENU
Brings up Marker Menu.
SCREEN DUMP
Initiates a screen dump to printer.
SAVE SPECTRUM
Brings up Save Spectrum menu.
RECALL SPECTRUM
Brings up recall spectrum menu.
SUBTRACT SPECTRUM
Brings up spectrum subtract menu. Spectrum subtract will subtract selected spectrum memory from currently displayed spectrum. The displayed spectrum is the working spectrum in the sense it is like another memory or register for spectrum information. If we call this Reg0 and spectrum memories Reg1 thru Reg10 then the subtraction performs the following operation:
Reg0 = absolute value ( Reg0 - RegX) where RegX is Reg1 thru Reg10.
.
OVERLAY ON/OFF
Allows recalled spectrums to overlaid on top of each other.
RECALL CAL SPECT
Brings Up calibration spectrum menu. These spectrums are used for self test evaluation. These spectrums are used for acceptance test.
CAL/DIAGNOSTICS MENU
Trouble Shooting
Typical symptoms indicating a problem are a flat or "pegged" sweep display
and no response to inputs. Blink is the test for trouble shooting interface problems.
BLINK
This is simple test routine that simply writes to all the data lines
going to the card an alternating pattern of ones and zeros. When BLINK is
run the LED should blink on and off about every second. If no blinking
occurs you have a communication problem with the PC host. Double check the
interface connections and the interface settings using SETUP. Check power