To Next PageTo Next PageWhat to do if Nautel Vector-LP VR250 shows Low AC Voltage?
If your Nautel Transmitter indicates a low AC voltage, and the AC source voltage is present, first check the AC breaker at the back of the transmitter. If the breaker is working correctly, then the interface PWB (A11) should be replaced, as this may be the cause of the issue.
What to do if Nautel Transmitter displays Over Current PS A or B?
If your Nautel Transmitter shows an 'Over Current PS A or B' error, replace the switch mode power supply PWB (A2 of the associated RF power module). If the transmitter is running in DC mode (optional) and the alarm is on the active side, replace the battery boost assembly A16. Otherwise, check the cabling between A7 and A3 through A6.
What to do if Nautel Vector-LP VR250 Transmitter displays High Temp PS A or B?
If your Nautel Transmitter is showing a 'High Temp PS A or B' error, check the fans to ensure they are spinning at an adequate speed (a minimum of 3000 RPM). If the fans are not spinning fast enough, replace the appropriate fan.
What to do if Nautel Vector-LP VR250 displays LVPS Fault A or B?
If your Nautel Transmitter indicates an LVPS Fault A or B, replace the associated AC/DC universal input power supply [side A (U2) or side B (U3)].
What to do if Nautel Vector-LP VR250 Transmitter displays Over Voltage PS A or B?
If your Nautel Transmitter displays 'Over Voltage PS A or B', replace the switch mode power supply PWB (A2 of the associated RF power module).
What to do if Nautel Transmitter shows Modulator Fail A or B?
If the Nautel Transmitter indicates a 'Modulator Fail A or B', check or replace the FETs on the power amplifier (A3 of the associated RF power module).
What to do if Nautel Transmitter displays RF Fail A or B?
If your Nautel Transmitter displays 'RF Fail A or B', it indicates a fault in a monitor PWB. If the fault is not accompanied by a specific fault indication, replace the exciter monitor/generator PWB [side A (A7) or side B (A10)].
What to do if Nautel Transmitter shows PDM Inhibit A or B?
If your Nautel Transmitter displays 'PDM Inhibit A or B', replace the RF synthesizer PWB [side A (A5) or side B (A8)].
What to do if Nautel Vector-LP VR250 displays Low NVRAM Bty?
If your Nautel Transmitter shows 'Low NVRAM Bty', change the active side of the exciter and run a standby side test on the power supply. If a fault is detected, replace the switch mode power supply PWB of the faulty power module. If no fault is detected, replace the interphase PDM driver PWB [side A (A6) or exciter B (A9)].
Details site preparation requirements before transmitter delivery and installation.
Lists criteria to be addressed when finalizing the transmitter site, including dimensions, weight, and clearances.
Emphasizes precautions against lightning-induced transients for transmitter protection.
Specifies requirements for a station reference ground to ensure a continuous, low impedance path to earth.
Details AC power source requirements, including surge protection and ferrite toroids.
Outlines requirements for AC and DC power sources used by the transmitter.
Describes the optional interface protection unit (SPU1) for preventing lightning-induced transients.
Details the external electrical interlock circuit connections and function for safety.
Explains how to control and monitor transmitter functions using remote interfaces or serial ports.
Outlines serial port features for interfacing with remote control centers and ATUs.
Describes optional remote control and monitoring via serial connection (RS-232, RS-422, modem, USB, TCP/IP).
Describes the optional surge protector panel for protecting against lightning-induced transients.
States that all assemblies are installed in the transmitter cabinet for shipping.
Provides instructions for connecting external control/monitor wiring to the remote interface PWB.
Details the procedures for installing AC power wiring, including interface protection unit connection.
Explains connecting the DC power source wiring to the transmitter's terminals.
Provides step-by-step procedures for performing commissioning checks and initial turn-on.
Outlines essential steps to verify the transmitter is ready for turn-on.
Details the initial turn-on procedure, including checking connections, GUI, and power status.
Explains the two types of emergency shutdown procedures: turning off RF output or complete shutdown.
Details how to turn off the RF output by inhibiting the power stage.
Explains how to perform a complete shutdown by disabling power supplies.
Describes the external electrical interlock circuit and its function in inhibiting RF output.
Provides precautions for handling assemblies with semiconductor devices susceptible to ESD damage.
Advises on electrically discharging personnel when handling assemblies.
Advises on protecting static-sensitive devices from unnecessary stress current by ensuring connections are not broken and voltages are not present on external circuits.
Recommends familiarizing oneself with controls and indicators before operating or diagnosing faults.
Describes the front panel as the primary local user interface, grouped into four sections: System Diagram, Control, Diagnostic Display, and Analog Meter.
Describes the diagnostic display as the primary local interface for control and monitoring of parameters.
Explains how to navigate the diagnostic display using the five pushbutton switches.
Details the high-level screens of the diagnostic display, including status bar and sub-menu selections.
Explains the information displayed on the transmitter status bar, such as time, power, and active side.
Explains how to view a list of current faults on the diagnostic display and attempt to clear them.
Describes controlling the active exciter side (A or B) and monitor mode (BYPASS or NORMAL).
Details how to view the stored transmitter events log, sorted chronologically with root-cause descriptions.
Explains setting high/low power thresholds, modulation, and keying loss limits to ensure acceptable operation.
Guides on determining parameters to be displayed on the front panel analog meter or diagnostic display's meters screen.
Explains how to select the transmitter's power source and view related parameters.
Guides on configuring the status of the audible alarm (sonalert) for all transmitter alarms.
Explains modifying timed shutdown parameters, including interval and auto-assert settings.
Describes restoring factory calibrated settings for parameters like thresholds and gain.
Provides steps to re-align out-of-tolerance meter readings on the diagnostic display.
Details adjusting critical transmitter shutback thresholds for RF current, AC voltage, and reflected power.
Explains adjusting maximum allowable output gain in terms of carrier reference.
Describes how to restore setup, calibration values, and thresholds to factory settings.
Guides on viewing and setting parameters related to auxiliary items like the keyer, ATU, or standby side.
Details setting up the keyer, including audio levels, modulation, and sequence parameters.
Explains how to check the software revision of various modules and view RF power module status.
Guides on viewing and editing control parameters for a Nautel antenna tuning unit (ATU).
Details testing the operation of the transmitter’s inactive (standby) side.
Explains configuring transmitter software for peripheral equipment like ATU or site interface PWB.
Explains configuring active logic states of control and monitor points for the NDB site interface PWB.
Details setting the site interface PWB’s control points and logic levels.
Explains setting the site interface PWB’s monitor points and their default/current values.
Guides on setting up the serial connection, including Tx Address, Modem Line, and Passkey.
Describes configuring the serial connection to automatically report transmitter alarms.
Guides on viewing power menu parameters and setting ATU current feedback status.
Warns about protection circuits monitoring critical parameters and potential power reduction or shutdown.
Outlines completing tests to verify transmitter circuits are within factory specifications.
Details the initial turn-on procedure after installation or major repairs.
Lists essential steps to be completed before performing functional tests.
Lists standard adjustments to be verified after transmitter commissioning.
Provides steps for adjusting the audio limiter threshold and verifying alarm reaction.
Guides on adjusting transmitter limits (power, modulation, tone) and monitor delay when using a standby side.
Explains verifying exciter changeover thresholds by adjusting power and modulation levels.
Provides steps for calibrating transmitter forward power and related parameters.
Details calibrating reflected power thresholds and the output network alarm by adjusting shutback levels.
Details how to read modulation levels using an oscilloscope and the diagnostic display.
Defines corrective maintenance as identifying and fixing defects or deficiencies that arise during operation.
Describes off-air troubleshooting when operation cannot be restored, including safe replacement of defective components.
Provides precautions for handling semiconductor devices susceptible to electrostatic discharge before removal or servicing.
Explains how to use the front panel and diagnostic display to determine fault occurrence and origin.
Explains how to replace an RF power module, noting diagnostic display messages indicate the faulty module.
Details the procedure for checking and replacing FETs, particularly those in RF power modules, using a digital multimeter.
Outlines replacing defective PWBs on the exciter panel and performing necessary adjustments.
Provides steps for replacing the battery boost assembly, including jumper settings and connection verification.
Explains the PDM fault detector circuit's role in controlling the shutback latch and on/off status of relay K1.
Describes the shutback latch circuit's function in inhibiting PDM output and RF output when faults are detected.
Explains the PDM inhibit circuit's function in clamping the PDM generator output to ground when faults or inhibit commands are sensed.
Details how modulation depth is controlled using digital pots and microcontroller adjustments.
Describes the control/monitor stage, including the control/display PWB, remote interface, and optional NDB site interface.
Describes how monitored parameters can initiate alarms and control transmitter functions when out of tolerance.
Describes the Complex Programmable Logic Device's role in reading alarm inputs, performing fault detection, and generating shutback outputs.
Details the diagnostic display (GUI) for navigation, control, and monitoring of transmitter functions.
Explains how control switches determine transmitter control location and RF status.
Explains that the RF power stage produces the transmitter’s final RF output, containing modules, filter, and probe.
Describes RF power modules, their output power, and internal components like amplifiers and modulators.
Explains the forward/reflected power probe circuit's components and how they sample RF output.
Describes the RF current probe circuit's components and how they provide RF current samples for detection and alarm.
General| Power Output | 250 W |
|---|---|
| Modulation | FM |
| Cooling | Forced Air |
| Maximum Power | 250 W |
| Input Voltage | 100-240 VAC, 50/60 Hz |
| Transmitter Type | Solid State |
| Frequency Range | 87.5 MHz to 108 MHz |
