The FCC regulates how much output power of any given transmitter. Since this is a fixed quantity, the system designers are forced to squeeze out every bit of performance out of the entire system.
Yes. If you are testing the line with the antenna attached, there is a good chance that the Site Master could be damaged by ESD. This happens because ESD gets onto the center conductor through the antenna's elements. It is safe to test with a load or short because there is no path for the ESD to get onto the center conductor.
An integrator failure is typically caused by excessive RF power to the input of the Sitemaster. Different Sitemaster models have different damage levels that they can tolerate and newer models have improved immunity to overpower conditions. See the appropriate user manual for the damage level for your particular unit. One common way this overpower condition can be caused is by a high powered interfering carrier when testing with the antenna attached at a co-locate site. If the power level of the interference is too high it could cause damage to the Site Master. To find out if damage has occurred, disconnect the Site Master from the coax under test and if the integrator failure still occurs then there may be damage to the unit. To prevent this type of situation, check the power level on the antenna first using a power meter or power monitor (Options 29 or 5) to see if any power is present on the antenna before sweeping it.
This is a problem with the database operations. It is caused when more than 2 lines of information have been added into the Plot Description field even if the extra lines are blank. To fix this, select the Record then select Edit. Place the cursor at the end of the 2nd line of the Plot Description field. Left-click and hold down the mouse button and scroll down. The cursor will now be below the 2nd line. Press the Delete key on the keyboard to remove the extra lines. The cursor should now be at the end of the 2nd line. Either select another record or select Done. To prevent this from happening on the initial entry of Plot Descriptions, try to remember not to press the Enter key when done with the 2nd line entry.
Basically, the maximum distance that can be measured in the DTF mode is controlled by 3 factors, 1) the data point resolution, 2) the frequency span or F2 minus F1 and 3) the propagation velocity entered for the coax under test. Since the propagation velocity cannot be changed, you must change either the frequency span or the data point resolution in order to go further. If using a 'B' or 'C' model, raising the data point resolution will almost double the distance. If you are using an 'A' or earlier model or cannot change the data point resolution then the frequency span will need to be smaller. Be sure to re-calibrate if the frequency span has to be changed.
The NiMH battery will last longer and perform better if allowed to completely discharge before recharging. For maximum battery life, it is recommended that the NiMH battery be completely discharged and recharged once every three months.
This is caused by opening a plot that has been saved by a higher version of the Site Master software, i.e. you can not open a plot that has been saved by v6.41in v6.31 or lower. The person trying to view the plot must upgrade their version of the software. NOTE: if, after opening the plot and seeing the problem, the user saves the plot it will corrupt it and will exhibit the same problem even when opened in the original version of software. Just opening the plot will not corrupt it.
After calibrating with the InstaCal, select measuring mode of Frequency vs. Return Loss. Connect a precision 10db attenuator and attach the short on the end of the attenuator. If the InstaCal calibration is accurate, the reading should be -20db.
All model "C" units have the external connector for power monitoring, but power monitor is an option (#5) and must be installed at the time of ordering or the unit must be returned for an upgrade. You will also need a power detector, which is an accessory. Check your users guide for a list of Anritsu Power detectors available for your unit.
Connectors! Improperly assembled or installed connectors cause a significant number of cell site problems. Many do not exhibit any problems at the time of commissioning, but much later as the elements take their toll on the system. This can often be found early during a maintenance period. By making similar DTF measurements at both the installation and the maintenance, changes in connector performance can easily be seen. Other sources of cell site problems include crimped, dented, crushed or punctured cables. Check your cable vendor's specifications for installation to be sure you exercise proper handling.
Yes the unit was calibrated in the factory. However to make accurate field measurements an OSL calibration should be made prior to the measurements. If the temperature changes sufficiently between the calibration and the measurement the Calibration Off display is a visible and a new calibration is required.
The calibration temperature window is different depending on the frequency range you are using. At the upper frequencies the window is +/- 5 degrees C from the temperature the calibration was done. In the first few minutes of operation there is a rapid increase in temperature inside the SiteMaster. This is why the Users Guide recommends a 5 minute warm up prior to calibration.
Calibration is absolutely necessary for good measurements. When you save a setup after calibration, assuming that you are using the "B" series Site Master, the calibration data is stored with the setup. As long as the temperature icon does not appear on the display you are in good shape. Now, if you listen to the design engineers, they are perfectly correct when they say that you may turn the Site Master off and then at a later day turn the unit back on and recall the saved setup with calibration. True statement. However, from a practical point of view, there is a temperature sensor mounted internally, which monitors the temperature of the PC Board. It is always good practice that when you turn the Site Master back on, that you allow it to warm up for about five minutes. Then recall the saved setup, re-calibrate and save it again over the same location. This eliminates the possibility that the temperature window was close to a limit. Especially in those areas where the outside temperature may change many degrees over the period of a day. Also, it is good practice to re-calibrate and save, when you have time to kill, such as while working up a tower. This may save you from suddenly seeing the temperature icon appearing as you make a measurement. Press "SYS" and "STATUS" to see the internal temperature range.
1. You can use Site Master to verify your adapters. The User's Guides of all of our Site Masters have a procedure for Return Loss Measurements. 2. When you measure the return loss of your adapter after an Open Short Load (OSL) calibration, please pay attention to the frequency range of the termination (load) used. For example, 7/16 load works to 8 GHz, SM/PL works to 4 GHz, 28N50-2 works to 18 GHz. 3. Adding another adapter between the adapter under test and the load will degrade the measurement of the return loss of the adapter under test. Plus if one adapter is really bad, you won't know which one is the culprit. 4. Perform the OSL calibration at the Site Master test port. The OSL calibration needs to be performed at the same place you will be connecting the adapter to be tested. Then attach an appropriate load. You are now measuring the return loss of the adapter. 5. Ultimately you have to have known good terminations and a known good Site Master to be able to perform these measurements. If you have more than one unknown, then it becomes very difficult to tell where the problem is. Anritsu offers calibration services for Site Master and also for the loads as well as some of the adapters. If you still are having problems, please consider sending your equipment in for calibration.
That depends! How well do you want to know the distance and loss of your system elements? The propagation velocity affects the distance that reflections are reported on the Site Master. Cable manufacturers often spec their prop v +/- 10%. So, the antenna at the end of your cable will have a +/- 10% error in distance. You can minimize this problem by sweeping known lengths of cable in DTF mode. You can 'dial in' the propagation velocity until the reflection at the end reads properly on the Site Master. The cable loss given by the manufacturers, however, is usually quite accurate. Using their published specification is sufficient. The Site Master cable tables offer both propagation velocity and loss values for many standard cables used in cell installations today.
The following limitation exists for most commonly used USB to Serial Adapters: The baud rate only goes from 9600 - 38400 kbs.
The "Battery Charging" indicator on the back panel will be lit when the battery is charging.
RL and SWR are frequency-based measurements, while DTF is a distance measurement. A mathematical formula uses the propagation velocity to convert frequency to distance. If the value isn't correct, it will affect the outcome of the formula.
The rule of thumb is that if you are in DTF (Return Loss Mode), then typically all connectors should be below -30, all cables should be below -40 as viewed on the vertical scale on the left hand side of the display. Again, depending on the cable run and antenna used (application); the antenna usually reads in the order of -15 to -20. However, application will dictate this whether you are operating in the 800 or 2000 MHz area or are using low band radio at 150 or 480 MHz. From this you can establish reference points which allow you to determine a connector pair at the junction of a jumper to the main feed line. Typically jumpers are about 2 meters long, so you should be able to establish your reference points from the length of the cable used.
Typical absolute measurement accuracy for tower mounted transmission lines is within 1 foot. Please see our application note "Distance to Fault" (page 12) for a more detailed explanation. This Application Note can be found on the SMIU Education page.
