REVISED ATTACHMENT D NAUTEL.pdf

ENGINEERING HANDBOOK 7 SECTION 4.4

Nautel Maintenance Schedule EHB-7 6/4/13

COMMUNICATIONS MAINTENANCE SCHEDULE - NAUTEL TRANSMITTERS

Operations Division

W/OPS12: JJE

SUBJECT: NWR Nautel Transmitter Preventive Maintenance Schedule and

Performance Measurements

PURPOSE: To provide periodic monitoring, maintenance, and performance measurements for the NOAA Weather Radio (NWR) Nautel transmitters. This ensures the quality of NWR broadcasts and the issuance of warnings to the listening public are within published specifications.

SITES AFFECTED: All Nautel model NWR Transmitter Sites

AUTHORIZATION: The authority for this modification is by National Weather Service (NWS) Headquarters direction.

VERIFICATION

STATEMENT:

The procedures were partially tested at the NWS Headquarters NWR Radio Room, Greer, SC, and the NWS Training Center

ESTIMATED COMPLETION

DATE:

Monthly: Remote Maintenance

Every 12 months: On-site Maintenance (if performed by the National Maintenance Contractor), or Every 4 or 6 months: On-site Maintenance (for dusty/dirty sites or if performed by NWS technicians or regional/local contractor technicians, at the Regional Headquarters discretion)

Annually: Signal strength measurements and 10 MHz calibration

TIME REQUIRED: Monthly remote maintenance: 15 minutes

On-site Maintenance: 2.5 hours

Annual field strength measurements: 8 hours

ACCOMPLISHED BY: NWS and/or contractor electronics technicians

Regional Maintenance Specialists

EQUIPMENT AFFECTED: Nautel model NG300/NG1000 (B262/B260) transmitters

SPARES AFFECTED: None

PARTS/MATERIALS

REQUIRED: Air filters (if required)

SOURCE OF

PARTS/MATERIALS:

National Maintenance Contractor (Contact NWS Headquarters either by phone or email for the Contractor information)

301-713-1847 x173

301-713-1847 x192

DISPOSITION OF REMOVED

PARTS/MATERIALS: Not applicable.

SECTION 4.4 ENGINEERING HANDBOOK 7

EHB-7 Nautel Maintenance Schedule 6/4/13 2

TOOLS AND TEST

EQUIPMENT REQUIRED:

Communications Analyzer (e.g., IFR FM/AM1200S/SS Comms Monitor with tracking function (option 12) or equivalent)

Ameritec AM-48(XT) Transmission Line Test Set [or equivalent sine wave frequency generator capable of 1000 Hz and 1 volt AC root-mean-square (RMS) output]

Portable computer (PC) with Nautel NG Series Remote Application (installed and configured)

Digital multimeter (DMM)

AC RMS voltmeter (e.g., HP 400E or equivalent)

Wattmeter or Power Meter/Sensor/directional coupler/laptop combination (e.g., Bird 43 with 25W, 50W, 100W, 250W, 500W, 1000W, 2500W elements

1500 Watt Dummy Load

Signal Strength Meter or Signal Strength Measurement System

Telephone buttset with RJ-11 modular adapter available

Two 3 foot type N male to N male RG142B/U cables (Pasternack

PE3455-36)

2 foot (25 inches end-to-end) DIN female to N male LMR-400 adapter cable

2 foot (25 inches end-to-end) N male to N female LMR-400 adapter cable

2 N male to BNC female adapters

DIN male to N male adapter

7/16-inch DIN male to N female adapter (Pasternack PE9179)

7/16-inch DIN female to N male adapter (Pasternack PE9178)

Type N male to N male adapter (Pasternack PE9007)

Type N female to N female adapter (Pasternack PE9006)

Two 4 foot BNC cables with BNC male on each end

(Optional) BNC cable, approximately 6 feet, BNC male one end, alligator clips on other end (if not using AM-48) and BNC Tee

RS-232 cable, 9 pin female to 9 pin male connectors (not Null Modem), 4 to 6 feet (part of Nautel accessory kit)

USB(A) to USB(B) printer cable, 4 to 6 feet

(Optional) USB(A) to RS-232 (male) adapter cable

Vacuum cleaner

Tool Kit (including a 12-inch Crescent wrench, #1 and #2 Phillips screwdriver, 3/8-inch nutdriver)

Trimpot Adjustment Tool (5-inch), GC 8608 (Contact East #191-470)

3 6/4/13

DOCUMENTS AFFECTED: Nautel Operations and Maintenance Manual, Section 4, Non-standard Maintenance.

Nautel NG300/NG1000 Operations and Maintenance Manual

NG300 Operations and Maintenance Manual

Generator and Automatic Transfer Switch operators/maintenance manuals

CRS Maintenance Manual, Appendix H, CRS System Alignment Procedures, Section H-6.2, DECtalk Synthesized Voice Output Level Adjustment

AM-48 Instruction Manual

Communications Equipment Maintenance Note 59, Revision A, ROAMS Sealed Lead-Acid Battery Replacement

Communications Equipment Maintenance Schedule NWR Transmitter EPG System: Kohler 12RES and 30RYG Engine Generator Set and MPAC 1500 Automatic Transfer Switch

PROCEDURE: Perform maintenance as specified in the following attachments:

ATTACHMENT A - Nautel Transmitter Site Preventive Maintenance Procedures

Part 1 - Preventive Maintenance Table for Nautel Transmitters

Part 2 - Preventive Maintenance Procedures for Nautel Model NG300/NG1000 Transmitters

ATTACHMENT B - Providing Audio Test Signals to the Transmitter

Part 1 - Generating the 1050 Hz Alert Tone using the CRS ACP

Part 2 - Generating SAME Burst Tones from the NWRSAME Hardware Panel

Part 3 - Generating SAME Burst Tones and Alert Tones from the CRS Application

Part 4 - Confirm Transmitter Transfer Using ACP and CRS Application

ATTACHMENT C - Ameritec AM-48 Transmission Test Set Initial Setup

ATTACHMENT D - IFR 1200 Communications Monitor to View Modulation and Deviation Setup

ATTACHMENT E - Nautel Transmitter Maintenance Record and Measurement Form

TECHNICAL ASSISTANCE: Jeffrey Earl: Jeffrey.Earl@noaa.gov 301-713-1833 x162 Greg Sikora: Greg.Sikora@noaa.gov 301-713-1833 x187 Ron DeWaters: Ron.Dewaters@noaa.gov 301-713-9478 x173 https://www.ops1.nws.noaa.gov/Secure/CRS/Maintmanual/AppH_rev10_2011.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/Maintmanual/AppH_rev10_2011.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/Maintmanual/AppH_rev10_2011.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/MaintNote/ComEquipMaintN59A_S.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/MaintNote/ComEquipMaintN59A_S.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/NWR_EGS_ATS_Maint_Schedule-1_signed.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/NWR_EGS_ATS_Maint_Schedule-1_signed.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/NWR_EGS_ATS_Maint_Schedule-1_signed.pdf mailto:Jeffrey.Earl@noaa.gov mailto:Greg.Sikora@noaa.gov mailto:Ron.Dewaters@noaa.gov

6/4/13 4

REPORTING

INSTRUCTIONS:

Report all NWR preventive maintenance activity using the Engineering Management Reporting System (EMRS) according to the instructions in EHB-4, Appendix G. Include the following information on the EMRS report:

Station ID (block 6): XXXXX (SID) Equipment Code (block 7): BXXX (see table 1) Serial Number (block 8): unit serial number

Table 1. NWR Transmitter Equipment Codes

EQUIPMENT TYPE EQUIPMENT CODE

Dual NWR 1000 Watt Transmitter (Nautel) B260 Dual NWR 300 Watt Transmitter (Nautel) B262

Deirdre R. Jones Director, Operations Division

Attachment A - Nautel Transmitter Site Preventive Maintenance Procedures Attachment B - WFO Procedures to Provide Audio Test Signals to the Transmitter Attachment C - Set-up for AM-48 Transmission Line Test Set Attachment D - Set-up for IFR 1200 Communications Monitor to Display Modulation and Deviation Attachment E - Nautel Transmitter Maintenance Record and Measurement Form

A-1 6/4/13

ATTACHMENT A - Nautel Transmitter Site Preventive Maintenance Procedures

PART 1 Preventive Maintenance Table for Nautel Transmitters

A.1.1 Routine Remote (Off-Site) Performance Monitoring The technician remotely monitors the transmitters at all sites on a MONTHLY basis to verify that parameters remain within specifications. For remote dial-in monitoring, the Nautel transmitters use ROAMS (Remote Off Air Monitoring System) and Nautel NG Remote Application software.

NOTE: Letters in braces { } refer to the applicable sections below Table A-1.

Table A-1. Remote Performance Monitoring Schedule for Nautel NWR Transmitters

All monitoring checks to be performed every month1

Maintenance Function Procedure Remarks

{A} Remote Check of Voice Broadcast Quality and Stored Fault Conditions

Install, set-up, and start the Nautel NG Remote Application but do not dial into transmitter until ROAMS is put to sleep (refer to the Nautel Operations and Maintenance Manual, Section 4, Non-standard Maintenance, Installing or Upgrading NG series Remote Application Software for software installation).

Dial into ROAMS using a touch-tone phone and check for alarms, audio input, and quality of ROAMS receiver broadcast audio. Put ROAMS to sleep.

Determine the problem if an alarm condition exists – a trip to the site may be necessary

{B} Remote Check of Exciter/Power Amplifier Currents, Supply Voltages, Transmitter Forward and Reflected Power, Antenna VSWR

Dial-in and monitor using the NG Remote Application.

Save the current configuration.

If any alarms are present or antenna VSWR is greater than 1.5:1 troubleshoot and correct as necessary {C} Ensure appropriate transmitter is broadcasting based on year: TXA for odd years, TXB for even years

Reference procedure to transfer as necessary.

Transmitter TXA should be broadcasting during odd years (e.g., 2011-TXA) and transmitter TXB should be broadcasting during even years (e.g., 2012-TXB).

{D} Disconnect from transmitter and save files

Disconnect/close remote application and attach configuration to the EMRS report.

1 Sites without a remote access phone line do not have to report these maintenance functions.

6/4/13 A-2

{A} Remote Check of Voice Broadcast Quality and Stored Fault Conditions

1. If the Nautel NG Series Remote Application is installed and site configured on a computer, skip to Step 9.

If not previously installed on a PC, download, install, and set-up the Nautel NG Series Remote Application (see next 3 steps for instructions). Refer to the NWS Transmitter Software and Firmware Updates for the latest application software:

2. In the NWR/CRS/WRIP section, click NWR Transmitter Remote Applications.

3. Log-In for access.

4. Go to the Nautel heading.

5. Click to download the latest remote application. (Reference the Nautel Operations and Maintenance Manual, Section 4, Non-standard Maintenance, Installing or Upgrading NG Series Remote Application Software for install procedures).

6. Click the Nautel icon on the desktop.

7. Select or type in the the following into the Connection window (see Figure A-1):

Site: <Site Name> Login: Remote(Modem) Username: Technician Password: <Available from the NWS Regional focal point> Interface: <COM port for the modem used to dial out > (Determine the correct COM port number using Windows Device Manager – under Ports or Universal Serial Bus Controllers.)

Phone Number: <Phone number of ROAMS line at Transmitter Site>

Figure A-1. NG Remote Application Connection Window

8. If this is the first use of the application, click Save site. If asked, answer yes to overwrite the connect setting. Minimize the NG Remote Application.

9. Start the Nautel NG Series Remote Application on a PC (unless already minimized) with a modem connected to an outside dial line. Under Site, select the appropriate <Site Name> but DO NOT click Connect. Minimize the NG Remote Application.

https://www.ops1.nws.noaa.gov/Secure/NWR/transmitter_softwre_firmwre.html

A-3 6/4/13

NOTE: Refer to the Nautel Operations and Maintenance Manual (NG300 or NG1000), Section 2:

Operating the Transmitter, NG Series Remote Application, for information on using the application.

10. Dial into ROAMS using a touch-tone phone.

11. Wait for the 3-4 second modem tone to end.

12. ROAMS will then enter human interface mode and report the site ID number.

13. Listen to the alarm status message. The ROAMS voice should state, Alarm Number 1 (or 2) inactive, indicating the alarm status of the inactive or standby transmitter.

Determine the problem if an alarm condition exists – a trip to the site may be necessary.

14. ROAMS will request a password. Immediately, key in the first digit (of the 3-digit code), waiting until the keystroke is echoed by ROAMS. Repeat for each of the other 2 digits.

Dial into ROAMS again if unable to enter password properly.

15. Press 3 to monitor NWR audio input for 20 seconds. The audio should be clear and undistorted. Wait until ROAMS asks for the next command.

16. Press 4 to monitor ROAMS receiver broadcast audio for 20 seconds. Listen for possible distorted audio, low power beeps, etc. Wait until ROAMS asks for the next command.

17. Press 1, listen to the status, then press 5 to put ROAMS to sleep allowing access to transmitter modem (but only for 2-5 minutes) and to terminate call.

18. Proceed immediately to dial into the transmitter using the Nautel NG Remote Application (previously minimized) by clicking Connect.

19. If sleep mode times out, repeat previous steps to put ROAMS back to sleep. The modem takes a few minutes to connect and then the application populates with transmitter parameters indicating connection to the transmitter.

If any connection failures or anomalies occur, contact the NWS Headquarters OPS17 NWR Engineer at 301-713-9478 x173.

6/4/13 A-4

{B} Remote Check of Exciter/Power Amplifier Currents, Supply Voltages, Transmitter Forward and Reflected Power, Antenna VSWR

1. Once the NG Remote Application connects to the transmitter, the parameters display on the screen (Figure A-2).

Figure A-2. Example with System Tab Selected and Showing TX A On, TX B Off

2. Using Table A-2, check the listed parameters.

Table A-2

Tab Selected Screen Section Screen Parameter Verification

System Status Forward Power Ensure Forward Power is ±10% of NTIA licensed power

System Status VSWR Less than 1.5:1

System Status Measured Frequency ±500 Hz of carrier frequency

System Control Active Transmitter Active transmitter per yearly or NWS regional guidance

A-5 6/4/13

3. From the System tab, Control section, click Standby Transmitter (…) (Figure A-3).

Figure A-3. Example with both TXA on and TXB on

4. Click down arrow, toggle to On and click Apply. The standby transmitter activates and should be running into the dummy load internal to the transmitter. With both transmitters running, this will allow a snapshot of every component of the system.

NOTE: The Site ID is the Call Sign from the NTIA license. The license should be posted on the transmitter. Contact the Regional Frequency Manager for a copy if it is missing.

5. On the System tab, verify that all Alarm/Status LED indicators are Green showing no faults present and the VSWR is below 1.5:1. If there is a fault, the event log capture shows the alarm.

6. Click Save state at the bottom of the Remote Application window. Figure A-4 displays.

6/4/13 A-6

Figure A-4. Save Select Channels

7. Ensure all channels are checked and then click Apply.

8. Select a folder in which to save the csv file.

9. Name the file <Site ID_yyyymmdd>_PMI.csv and save the current configuration.

CAUTION

The following step is very important so that the secondary transmitter is not left transmitting into the dummy load.

10. From the System tab under Control, select the Standby Transmitter box, and toggle to OFF and then Apply.

11. Ensure the secondary transmitter is Off by verifying the RED Alarm/Status LED is ON beside the secondary transmitter (TX A Status or TX B Status).

A-7 6/4/13

12. If any of the Alarms were present or the VSWR is greater than 1.5:1, select the Events tab, click Save events (Figure A-5), and download the Eventlog file to the PC.

Figure A-5. Sample Eventlog

13. Select a folder in which to save the csv file.

14. Name the Eventlog file using the following convention:

<Site ID_yyyymmdd>_EVT.csv

15. Using Table A-3, check the listed parameters:

Table A-3

Tab Selected Screen Section Screen Parameter Verification System Status TX A Deviation Peak Less than 5.0 Khz

System Status TX B Deviation Peak Less than 5.0 Khz

If the deviation is greater than 5.0 kHz, adjustments need to be made with a site visit.

6/4/13 A-8

16. Click the Configuration tab (Figure A-6) to verify the following Firmware version blocks are current.

Figure A-6. Remote Application Configuration Screen

17. Refer to the NWS Transmitter Software and Firmware Updates: In the NWR/CRS/WRIP section, click NWR Transmitter Firmware Updates, Log-In for access, go to the Nautel heading, then check the website Configuration screen for firmware version updates:

System controller firmware version Transmitter A firmware version Transmitter B firmware version

18. If the firmware is newer on the website, refer to the NG300 (or NG1000) Operations and Maintenance Manual, Section 4: Non-Standard Maintenance, upgrading Software, to update the transmitter firmware.

A-9 6/4/13

{C} Ensure appropriate transmitter is broadcasting based on year: TXA for odd years, TXB for even years Transmitter TXA should broadcast during odd years (e.g., 2011-TXA); transmitter TXB should broadcast during even years (e.g., 2012-TXB). If not, do the following:

From the System tab, Control section, change the Active Transmitter parameter to the appropriate transmitter according to the year.

TXA for odd years TXB for even years

{D} Disconnect from transmitter and save files

1. Click Disconnect then Close the application.

2. Attach the csv files (PMI and EVT if saved) to the EMRS A-26 page and send to the appropriate NWR site point of contact.

A.1.2 On-Site Routine Maintenance Perform routine maintenance every 4, 6, or 12 months, depending on who is performing the maintenance and the transmitter site conditions (or by Regional Headquarters discretion), according to the requirements stated in the maintenance schedule, Table A-4. On-Site Preventive Maintenance and Performance Measurement Schedule – Nautel.

When a corrective maintenance service call is made at a transmitter site, perform the routine maintenance operations listed in Table A-4.

If no trouble call is received from a station within a 6-month period, make a special visit to perform routine maintenance.

The maintenance data log attached to the transmitters must be updated after each maintenance action and a copy of the log submitted to the designated Government offices. In addition, the Nautel Transmitter Maintenance Record and Measurement Form (Attachment E) should be completed as the maintenance functions are performed. Alternatively, instead of filling out Attachment E for Maintenance Functions {4}, {5}, and {6}, the Nautel Application can be used to save the transmitter parameters to a CSV file which is subsequently attached to the EMRS A-26 page.

Upon completion of routine maintenance, the transmitter system must be made fully operational and functional at the authorized output power, within required frequency and modulation tolerance, and in compliance with all technical descriptions and specifications of the manufacturers’ equipment manuals.

Twenty-four (24) to 48 hours prior to the scheduled transmitter preventive maintenance visit (or prior to a corrective maintenance visit where routine maintenance is also performed), the CRS Maintenance Manual, Appendix H, CRS System Alignment Procedures, selected procedures (H.1, H.2, H.4, H.4.1, H.4.2, H.4.3, H.6, H.6.1 and H.6.2) (can be downloaded from the Operations Division website) must be performed by the WFO El Tech using the AM-48 Test Set to verify that the CRS levels leaving the WFO are set properly for the Alert Tones and transmitter Transfer Tones from audio control panel (ACP)1 and ACP2, SAME tone generated by the NWRSAME Panel, and the Alert, Transfer, and SAME tones generated by the CRS Application/DECtalk Card to the appropriate transmitter to be tested.

Twenty-four (24) hours prior to the start of on-site transmitter maintenance, the transmitter technician must contact the associated WFO to request a Public Information Statement (PNS) be issued advising the public that the transmitter will be undergoing maintenance and broadcasts may

6/4/13 A-10 be periodically interrupted. For the audio input level tests (Maintenance Function {8}, Transmitter Audio Input Level Verification), the technician will request that the WFO transmit the alert tone and SAME tones for the purpose of verifying proper signal level on the transmitter audio program line (described in Attachment B, Parts 1 through 4). Any change in audio input level outside the specifications must be reported to the WFO maintenance focal point.

CAUTION

For maintenance function number {8}, the transmitter output MUST be into a dummy load.

NOTE: Numbers in braces { } refer to the applicable sections of Attachment A, Part 2

Table A-4. On-Site Preventive Maintenance and Performance Measurement Schedule – Nautel

All maintenance and performance measurements to be performed every 4, 6 or 12 months.

Maintenance Function Procedure (Refer to the detailed procedures in Attachment A, Part 2) Remarks

{1} Clean or replace air filters

Clean modules, fans, and system cabinet

Vacuum and brush any dirt from the cooling fans.

Vacuum any dirt from the base of the transmitter system cabinet.

Power off the appropriate transmitter and circuit breaker prior to performing.

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{2} Visual Inspection of chassis and Operational Check of Cooling Fan(s)

Visually check for signs of burned or broken components/assemblies and loose or damaged cables. Check for proper operation of cooling fans (and if noisy).

Take corrective action as needed.

{3} Check AC Input Voltage, AC Surge Protectors, Lamps, LEDs, Readouts/Displays, and ROAMS battery date

Measure AC input voltage. Visually check all surge protectors, lamps, LEDs and readouts to ensure that they indicate at proper times. Check the ROAMS battery date code. Replace as necessary.

Replace ROAMS battery if over 4 years old.

{4} Transmitter Forward and Reflected Power Verification

Record readings and compare with previous readings.

High reflected power may indicate a bad cavity, antenna cable or antenna

{5} Transmitter Exciter/Power Amplifier Supply Voltage and Current Verification

Record readings and compare with previous readings.

If any voltages or currents abnormally high or low, troubleshoot

{6} Transmitter Carrier Frequency Verification

Carrier frequency must be within ±200 Hz. Adjust if necessary

A-11 6/4/13

All maintenance and performance measurements to be performed every 4, 6 or 12 months.

Maintenance Function Procedure (Refer to the detailed procedures in Attachment A, Part 2) Remarks

{7} Transmitter Voice Modulation and Deviation Level and Quality Verification

Frequency deviation must not exceed ±5 kHz.

Use a Comms Analyzer - warm up for at least 30 minutes

{8} Transmitter Audio Input Level Calibration and Verification

a. External Source Input Level Calibration

b. 1050 Hz Alert Tone

c. NWRSAME signal level from hardware panel

d. NWRSAME and alert tone level from CRS Console

24 to 48 hours prior to visit, perform selected procedures (H.1, H.2, H.4, H.6) from CRS System Alignment, Appendix H, CRS Maintenance Manual

Disconnect audio input line from WFO, inject -10dbm, 1kHz signal at input to transmitter, verify 4.5KHz deviation on IFR Comms Monitor

Alert Tone and SAME signals are generated at the WFO and measured at the transmitter audio input using a communications monitor. The WFO will perform the procedures in Attachment B.

Ensures proper output levels at the WFO from CRS ASM card

Ensures proper deviation using an external audio signal source at the transmitter input

Test tones are generated at the WFO

{9} Verify Proper Transmitter Transfer using ACP and CRS Console Software Application;

Final transfer to appropriate transmitter (dual transmitters only)

Call the appropriate WFO and have the operator switch transmitters using the CRS Audio Control Panel and CRS console software application; WFO to execute final transfer to odd year (e.g., 2011-TX1) or even year (e.g., 2012-TX2) transmitter

ROAMS still disabled when switching transmitters

See Note 4 below

{10} Backup Generator and Automatic Transfer Switch Checks and Testing (NWS owned)

Check all fluid levels. Visually check generator for fluid leaks, damage, or debris.

Test automatic transfer switch (if applicable) and generator.

Only to be performed on NWS owned equipment. Contact appropriate NWS Regional point of contact for site specific generator guidance.

NOTE: 1. Test equipment used for the procedures must have a current calibration certificate and date sticker traceable to the National Institute of Standards and Technology

(NIST).

2. Warm up the Communications Analyzer at least 30 minutes prior to using it for measurements.

3. After procedure {8} in the above table has been performed, the antenna cable will be disconnected from the dummy load and reconnected to the antenna.

4. Procedure {9} attempts to equalize the operating time for each transmitter (dual models) and to simplify which transmitter should be broadcasting at a given time.

6/4/13 A-12

Table A-5. Off-Site Performance Measurement Schedule for Nautel Transmitters

All measurements to be performed once per year.

Maintenance Function Procedure Remarks

{11} Signal Strength Measurement

Refer to the procedures in Attachment A, Part 2

Time interval: 9 to 13 months

Normally performed by NWS technicians or Regional Maintenance Specialists.

{12} 10 MHz System Console Output Verification

10 MHz calibration and alignment

A-13 6/4/13

PART 2 Preventive Maintenance Procedures for Nautel Model NG300/NG1000 Transmitters

A.2.1 WFO Notification of Maintenance, Inhibiting ROAMS Dial-out, Power Down

NOTE: Twenty-four (24) hours prior to the start of on-site transmitter maintenance, the transmitter technician must contact the associated WFO to request a Public Information Statement (PNS) be issued advising the public that the transmitter will be undergoing maintenance and broadcasts may be periodically interrupted (specify start time and number of hours).

1. Disconnect the ROAMS phone line from the Telephone Network Interface box (or associated RJ11 jack) so ROAMS will not call the WFO when transmitter maintenance is being performed. The ROAMS phone line may then be used to communicate with the

WFO.

2. Listen to the NWR broadcast to verify the special PNS maintenance statement is being broadcast. If not, contact the lead forecaster at the controlling WFO and request that they issue a Public Information Statement (PNS) advising the public that the transmitter will be undergoing maintenance and broadcasts may be periodically interrupted.

3. Turn on and warm up the Communications Monitor (e.g., IFR 1200S). Set up the Comms Monitor for the proper frequency (see Attachment D for the IFR 1200 setup).

The warm up time is approximately 30 minutes.

4. Transfer to Local control: On the Nautel system controller front interface panel, select the BACK switch to return to the Status Menu display, then press the LOCAL switch (ensure the red LED on the LOCAL switch is lit). The transmitter system can now be controlled via the system controller’s front panel interface or with a PC with the Nautel NG Remote Application. All remote control circuits (except the external interlock) are disabled.

5. A PC with the Nautel NG Remote Application software installed can now be connected to the local serial or USB port of the front controller panel using the appropriate cable. If connecting for the first time, the order of preference to connect to the controller is:

a. The Nautel RS232 cable (e.g., COM1)

b. A USB to RS232 adapter cable (using the driver CD) plus the Nautel RS232 cable (e.g., COM6)

c. A USB (A) to USB (B) printer cable (e.g., COM7)

6. Once connected to the controller panel, confirm the COM driver was correctly installed, and note the COM port number under Windows Device Manager (under Ports or Universal Serial Bus Controllers). This number is needed when selecting the proper Nautel application Interface selection. Refer to the Nautel Operation and Maintenance Manual, NG Series Remote Application for interfacing to the front controller panel.

6/4/13 A-14

7. Click the Nautel icon on the desktop. The Connection window displays (Figure A-7).

Figure A-7. Remote Application Connection Window

8. Perform the following:

Site: Select or type in Direct Login: Local(RS232/USB) Username: Technician Password: <Available from the NWS Regional focal point> Interface: <COM port> for the RS232 or USB cable Baudrate: 19200

9. Click Save site if this is the first use of the application. If asked, answer yes to overwrite the Direct connect setting.

10. Click Connect. The application populates with transmitter parameters indicating connection to the transmitter. If at any time power is turned off to the transmitter, reconnect to this monitor application.

NOTE: The following procedures describe the control and reading of the transmitter parameters using the System Controller front panel switches and/or a PC with the NG Series Remote Application.

11. Turn OFF the non-broadcasting (standby) transmitter:

Using a PC with NG Remote Application: From the System tab, Control section, click the Standby Transmitter (…) button, click the down arrow, toggle to Off and click Apply. The standby transmitter will turn off.

12. Using the NG300/NG1000 System Controller front panel: press BACK, as necessary, then SELECT until the Main Menu displays.

13. Using the UP or DOWN buttons, align the arrow (>) with Control, then press the SELECT button. From the Control menu, use UP or DOWN to align the arrow with Standby TX On/Off and press SELECT, then use UP or DOWN until the arrow (>) is aligned with Off, then press SELECT to turn the standby transmitter OFF.

14. Turn OFF the power switches in the back of the Power Amplifier (“VHF transmitter”) chassis for the non-broadcasting transmitter (the Nautel controller External Alarm red LED for that transmitter will turn on).

A-15 6/4/13

15. Locate the appropriate circuit breaker in the NWR transmitter main electrical panel box, then turn the circuit breaker for the transmitter to be cleaned to the OFF position and use standard Lock Out/Tag Out (LO/TO) procedures to secure the breaker.

{1} Clean or Replace Air Filters, Clean Modules, Fans, And System Cabinet (Non-broadcasting Transmitter)

(Refer to Section 3 in the Nautel NG300/NG1000 Operations and Maintenance Manual.)

1. Remove dust from the cabinet, chassis, and panels with a soft-bristled brush and vacuum. Clean flat surfaces and accessible areas with a lint-less cloth moistened with rubbing alcohol. Dry with clean, lint-less cloth.

2. There is one filter for each of the RF power amplifier panels. To clean or replace:

a. Remove the front panel grill section by removing the four captive M4 hex screws using the HY88 hex tool from the ancillary kit. Do NOT try to pull out the screws from the grill or the captive washers will fall out – they are not held in very firmly.

b. Temporarily remove the PVC retaining plate from the grill section then remove the old filter.

c. Vacuum the filter (or, if possible, rinse with water, then dry thoroughly before replacing), and both sides of the filter grill.

d. If unable to clean properly or if the filter is damaged, replace the filters. Replacement filters are available from the national maintenance contractor using the following part numbers:

For Model NG300: HAM74

For Model NG1000: HAM75 (Nautel) or Universal Air Filter, 25 PPI Quadrafoam Media, Black

3. Re-install the air filters, PVC retaining plate, and front grill (the grill is not reversible and only fits in one way).

4. If in an extremely dirty environment, for the non-broadcasting transmitter:

a. Ensure the transmitter and circuit breakers are OFF. Use standard Lock Out/Tag Out (LO/TO) procedures to secure the breaker.

b. Disconnect the power control and any other cables from the back of the chassis.

c. Pull out the chassis from the rack.

d. Remove the top cover plate (16 screws).

e. Use dry and oil-free compressed air, soft bristle brush, and vacuum to remove any dust that accumulates on modules, circuit cards, and other components.

f. The fans inside the chassis need to be cleaned at least once a year.

5. Record which filters were replaced in Attachment E.

6/4/13 A-16

{2} Visual Inspection of Chassis and Operational Check of Cooling Fans

1. Check for signs of burned or broken components/assemblies and loose or damaged cables.

2. Remove the front panel grill of the broadcasting transmitter (see section {1} step 2) and ensure all the cooling fans (5 in the 1000W, 3 in the 300W, plus one in the front upper left side) of the broadcasting transmitter are operating properly and not abnormally noisy (may need to use a flashlight).

3. Record the location of any failed or defective fans in Attachment E.

{3} Check AC Input Voltage, AC Surge Protectors, Lamps, LEDs, Readouts/Displays, and ROAMS Battery Date

1. Check the AC input voltage by using a Multimeter to measure at the bottom terminals in the back of the cabinet. Remove the rear cabinet cover and measure voltage between L1 and L2 on both TB1 terminal blocks. Depending on the transmitter model and type of power supplied, the input voltage should be 115 VAC ±10%, 208 VAC ±10% (three phase), or 230 VAC ±10% (single phase). Contact the site line power point of contact if outside the ±10% range.

2. Check the indicator lights on the AC surge protectors (by the AC Breaker/Power Panel) to ensure they are still properly protecting the power line (2 green LEDs are on). Replace the protector as necessary. Check the LEDs and LCD displays of the broadcasting transmitter. Record all information in Attachment E.

3. Check the battery date code written on the outside of the ROAMS chassis (if no date was written on the outside of chassis, battery must be removed from ROAMS chassis and examined - refer to NWR Maintenance Note 59 Rev A). The date code format of the Power-Sonic model PS-612 is MO DD Y M (where MO = month, DD = day, Y = year, and M = mfr. use. For example: 12144L is Dec. 14, 2004). The format of the Panasonic model LCR6V1.3P is Y MO DD (where Y = year, MO = month, and DD = day. For example: 041214 is Dec. 14, 2004). Record the battery date in Attachment E. Replace the battery if over 4 years old with a Power-Sonic model PS-612 (or Panasonic LCR6V1.3P). Refer to NWR Maintenance Note 59 Rev A (ROAMS Sealed Lead-Acid Battery Replacement) for the replacement procedures.

NOTE: The transmitter parameters measured in Maintenance Functions {4}, {5}, and {6} may be saved in the Nautel Application to a CSV file instead of recording in Attachment E.

{4} Transmitter Forward and Reflected Power Verification

NOTE: Skip steps 1 through 5 if the external power meter is already attached to the antenna.

1. Turn off the broadcasting transmitter prior to attaching an external power meter:

Using System Controller panel: Push in the red RF OFF switch. The broadcasting transmitter turns OFF and the green LED on the RF ON switch no longer is lit.

Using PC: From the System tab, Control section, click the Main Transmitter (…) button, click down arrow, toggle to Off and click Apply. The main or broadcasting transmitter will turn off.

2. Turn OFF the power switches in the back of both the power amplifier chassis - the transmitter that had been broadcasting and the standby.

https://www.ops1.nws.noaa.gov/Secure/CRS/MaintNote/ComEquipMaintN59A_S.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/MaintNote/ComEquipMaintN59A_S.pdf https://www.ops1.nws.noaa.gov/Secure/CRS/MaintNote/ComEquipMaintN59A_S.pdf

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3. Locate the appropriate circuit breaker in the NWR transmitter electrical panel box, and then switch the circuit breaker for both the transmitters to the OFF position. Ensure all transmitters are OFF. Use standard Lock Out/Tag Out (LO/TO) procedures to secure the breaker.

4. Carefully remove the antenna transmission line from the cavity RF directional coupler taking care not to bend it.

NOTE: The Bird 43 wattmeter is most accurate when reading full scale. It is therefore recommended to use the elements specified in the next step.

5. Install the appropriate calibrated external power meter, directional coupler, or power sensor (use appropriate element for a Bird 43 - 500W element for NG300, 1000W element for NG1000) between the cavity RF directional coupler connector and the antenna cable (a 7/16 DIN male to Type N female adapter may have to be used along with a 25 inch LMR-400 Type N male to male cable to prevent the heliax from bending.

The proper cable length is necessary to maintain antenna cable phasing).

6. Switch the circuit breaker for the transmitter that had been broadcasting to the ON position.

7. On the transmitter that had been broadcasting, turn ON the power switches in the back of the power amplifier chassis.

8. Turn ON the transmitter that had been broadcasting:

Using PC: From the System tab, Control section, click the Main Transmitter (…) button, click down arrow, toggle to On and click Apply. The transmitter that had been broadcasting will turn ON.

Using System Controller panel: Press the BACK button as necessary then the SELECT button until the Main Menu displays. Using the UP or DOWN buttons, align the arrow (>) with Control, then press SELECT. Use UP or DOWN buttons to point to Set Active TX then press SELECT. Use UP or DOWN buttons to point to TXA or TXB and press SELECT to turn ON the transmitter that had been broadcasting. On the System Controller panel, push in the RF ON switch.

9. The green LED on the RF ON switch is lit, and either the Transmitter A (TXA) or Transmitter B (TXB) green LED is lit.

10. Record the forward and reflected power value from the external power meter in Attachment E and compare with previous readings. (Reflected power measurement for Bird 43 Wattmeter only: Note the position of the arrow direction of the power element currently installed in the wattmeter used to measure the forward power. Remove that element and replace it with a 50-watt element insuring the arrow on the element is in the OPPOSITE DIRECTION that the forward element was in. The arrow should be pointing AWAY from the transmitter antenna cable. Read the value on the meter. The forward power reading should be within 5% of the external wattmeter reading. If reflected power is more than 4% of forward power, perform corrective action.

11. Observe the Fwd/Rfl Power on the System Controller Vacuum Florescent Display (VFD) for the active transmitter (TXA or TXB) or the Forward Power and Reflected Power on the PC. If the Forward Power is outside ±5% of the normal operating power, corrective action must be taken. If slightly outside the tolerance, adjust the forward power by referring to the next step below. Note that the scaling factor is normally 1.00 and that any

6/4/13 A-18 change to this will affect the output power level. If no adjustment is necessary, go to Step 12. If necessary, adjust the forward power as follows:

Using PC: Click the SYSTEM tab and note the FORWARD POWER and REFLECTED POWER readings. From the System tab, Control section, click the System Forward Power (…) button. Compare the reading with that of the external wattmeter. Enter the corrected value in the window.

Using System Controller Panel: Press SELECT (or BACK if necessary) to get to the Main Menu. Use UP and DOWN buttons to point to Control and push SELECT then use UP and DOWN buttons to point to System Fwd Power and push SELECT. Use UP and DOWN buttons to increase or decrease the power setting (in 1 W steps). Note that an increase or decrease from the previously stored value will cause an asterisk to appear at the end of the screen’s top line. Press SELECT to confirm the setting. Press BACK to read the Fwd/Rfl Power on the Controller Display. Compare the reading with that of the external wattmeter.

12. Record the final forward and reflected power and VSWR values in Attachment E (and the site log) as follows:

Using PC: Click the SYSTEM tab and note the FORWARD POWER, REFLECTED POWER, and VSWR readings. Click on the TXA Meters or TXB Meters and note the same readings. Record the values for forward and reverse power and VSWR in Attachment E.

Using System Controller Panel: On the System Interface front panel, press SELECT (or BACK if necessary) then the UP or DOWN buttons until the arrow points to Meters on the LCD screen. Press the SELECT button. Under the Meters menu press SELECT to choose TXA or TXB. Use the UP and DOWN buttons to scroll through and show the power amplifier voltage and currents for TXA or TXB (PA Volts, PA1 Current, PA2 Current). Record the values in Attachment E.

{5} Transmitter Exciter/Power Amplifier Supply Voltage and Current Verification Using PC: Click the SYSTEM tab and note the FORWARD POWER, REFLECTED POWER, and VSWR readings. Click the TXA Meters or TXB Meters and note the same readings. Record the PC readings in Attachment E and compare with the previous readings.

Using the System Controller panel: Press SELECT (or BACK if necessary) then the UP or DOWN buttons until the arrow points to Meters on the LCD screen. Press the SELECT button. Under the Meters menu, press SELECT to choose TXA or TXB. Use the UP and DOWN buttons to scroll through and show the power amplifier voltage and currents for TXA or TXB (PA Volts, PA1 Current, PA2 Current). On the PC, select the TXA Meters or TXB Meters tab to obtain the power amplifier supply voltages, currents, and fan speeds. Record the front panel readings in Attachment E and compare with the previous readings.

{6} Transmitter Carrier Frequency Verification Using a communications analyzer: With an antenna attached to the RF input connector, verify the carrier frequency is within ±200 Hz of the specified frequency (for the IFR 1200S:

use the ANT input, setup according to Attachment D, set the FREQUENCY ERROR switch to RF-300, then perform Attachment D, step 4). Record the initial carrier frequency reading in Attachment E. If more than 500 Hz off assigned carrier frequency, perform corrective action below.

A-19 6/4/13

DO NOT proceed with this fine frequency adjustment without a properly calibrated Communications Analyzer or Frequency Counter. To perform a fine adjustment of the carrier frequency: From the Main Menu, press the SELECT button, then use the UP and DOWN buttons to point to Control and push SELECT. From the Control menu use the UP and DOWN buttons to point to Carrier Trim and press SELECT. Use the UP and DOWN buttons to adjust the proper carrier trim (in Hz) to get back to the proper carrier frequency.

Using a PC: With the Nautel NG software, click the Calibration tab, then select Carrier Trim by clicking the … box next to the trim value. Increase or decrease the Carrier Trim up or down as necessary by typing in the new value, then click Apply. Check to see if the frequency error is within the above limits. If not, repeat. Record the final carrier frequency reading in Attachment E.

{7} Transmitter Voice Modulation and Deviation Level and Quality Verification

1. Connect a short antenna to the RF input connector of a communication analyzer. If using an IFR 1200S analyzer, use the ANT input and set the METER selector to 6 kHz, VERTICAL selector to 2 kHz per div., HORIZONTAL selector to 1 ms per div. (or set to Tone if needed).

2. With a standard voice audio input from the CRS, check the modulation value on the meter and the deviation on the CRT. Verify that the nominal value is about ±4.5 kHz on the CRT and 4.5 kHz on the modulation meter and does not exceed ±5 kHz. There is no deviation adjustment. If it is excessive or clipping, first perform Procedure {8} to verify proper audio levels prior to troubleshooting the transmitter. Record the readings in Attachment E.

NOTE: Skip to Procedure {8}, Transmitter Audio Input Level Calibration and Verification, if maintenance on both transmitters has been completed or if completed on a single transmitter installation.

A.2.2 Repeat Maintenance for Backup Transmitter

1. For the non-broadcasting transmitter, switch the circuit breaker for that transmitter to the

ON position.

2. On the non-broadcasting transmitter, turn ON the power switches in the back of Power Amplifier chassis.

3. Using the System Controller front panel, Press the BACK button as necessary then the SELECT button until the Main Menu displays. Using the UP or DOWN buttons, align the arrow (>) with Control, then press the SELECT button. From the Control menu, use UP and Down buttons to align the arrow with Set Active Tx and press SELECT. Use the UP and DOWN buttons to point the arrow to TXA or TXB as appropriate (whichever transmitter that was not previously broadcasting). Press the SELECT button to confirm the change. The transmitter that had not been broadcasting should now be on.

4. Turn OFF the non-broadcasting (standby) transmitter: Press the BACK button as necessary then the SELECT button until the Main Menu displays. Using the UP or DOWN buttons, align the arrow (>) with Control, then press the SELECT button. From the Control menu, using the UP or DOWN button, align the arrow (>) with Standby TX On/Off, then press the SELECT button. Move the UP or DOWN button until the arrow (>) is aligned with Off, then press SELECT to turn the standby transmitter OFF. The previously broadcasting transmitter should now be OFF.

6/4/13 A-20

5. For the transmitter that had been broadcasting, turn OFF the power switches to the Power Amplifier chassis.

6. Locate the appropriate circuit breaker in the NWR transmitter main electrical panel box, and then turn the circuit breaker for the transmitter to be cleaned to the OFF position.

Use standard Lock Out/Tag Out (LO/TO) procedures to secure the breaker.

7. Repeat maintenance functions starting from {1} through {7} for the backup transmitter.

{8} Transmitter Audio Input Level Calibration and Verification

1. Turn off the primary and backup transmitter: On the System Controller panel, push in the red RF OFF switch. The green LED on the RF ON switch turns off.

2. On the broadcasting transmitter, turn OFF the power switch to the Power Amplifiers.

3. Locate the appropriate circuit breaker in the NWR transmitter electrical panel box, and then switch the circuit breaker for the transmitter to the OFF position. Ensure all transmitters are OFF. Use standard Lock Out/Tag Out (LO/TO) procedures to secure the breaker.

4. Remove the external Power Meter from the cavity and install an external 1500 watt Dummy Load in place of the Antenna Transmission Line using the appropriate adapters and cables.

5. On the primary and backup transmitters, turn ON the transmitter circuit breaker panel switches.

6. Turn ON all the power switches to both the Power Amplifiers.

NOTE: The transmitter should still be in LOCAL control (red LOCAL LED on).

CAUTION

During the following steps, warning alert tones are output from the transmitter. The broadcasting transmitter output MUST be connected to the dummy load instead of the Antenna so the warning tones are not sent out to the public.

{8}a Transmitter External Source Input Level Calibration

1. Set up the AM-48(XT) according to Attachment C (for baseline settings). If the AM-48 is not available, set up a sine wave frequency generator to input a 1000 Hz tone at 245 mV AC RMS then skip to step 7.

2. Set the ABS/REL/SEND switch to SEND.

3. Set the MF/DTMF/SHIFT key to SHIFT

4. Press the A key, LEVL: 0.0 displays.

5. Using the keypad, enter 1 0 0 and press the D key (±). LEVL -10.0 displays.

6. Press the A key again. LEVL -10.0 displays.

7. Using the SEL….SEND switch (SW 6), push the switch until the SEND parameter shows 1004 near the bottom of the display. The AM-48 displays -10.0 1004.

A-21 6/4/13

8. Locate the telephone line (audio feed) surge suppressor (U4) located on the top shelf in the rear of the transmitter cabinet (same area as the ROAMS and Dial Modem).

9. Remove the NWR audio feed coming from Telco or UHF link. This is on the NETWORK (or LINE) side of the suppressor pins 1 and 2 and is typically the ORG/WHT pair.

10. Connect the RED and GREEN leads of the AM-48 (or other audio frequency source) to pins 1 and 2 of the NETWORK (or LINE) side of the suppressor. If not using the AM-48, skip to step 13.

11. Set the 2W/4W/4W REV switch to 2W and the TERM/BRDG switch to BRDG.

12. Place the MON REC/MON SND/TALK switch to MON SND. The AM-48 should be sending a level of -10 dBm.

13. Change the ABS/REL/SEND switch from SEND to ABS. The display may change to a value of 9.1dBm or stay at -10dBm.

14. Confirm the level at the telephone line (audio feed) surge suppressor using a true RMS voltmeter. The level should be about 245 mV AC or at least between 0.275 and

0.218 volts (-9.0 to -11 dBm).

NOTE: Some transmitters do not have a true 600 Ohm load; therefore, variations of actual levels occur. Levels from -9.0 to -11 dBm are acceptable. Because of this, the levels at the audio source may vary depending on the actual audio load of the transmitter.

15. AM-48 only: If output does not seem correct, perform the following steps to verify the AM-48 is outputting the correct level:

a. Remove the GRN/RED AM-48 leads from the input to the transmitter.

b. On the AM-48, connect the GRN to YEL and the RED to BLK. This ties the TX and RX together and loops the audio back into the AM-48.

c. Set TERM/BRIDGE to TERM. This supplies a calibrated 600 Ohm load.

d. Set the following :

2W/4W/4W REV to 4W

ABS/REL/SEND to SEND

SEL….SEND section to 1004

e. The display should read 1004 -10.0.

f. Using the RMS multimeter, measure across the GRN/YEL and RED/BLK – it should read 245 mV AC RMS.

g. Further verification can be seen by changing the MON SND/MON REC/TALK to MON SND and then MON RCV. The AM-48 indication will show -10.0 1004 in both positions. The indication shows the AM-48 is putting in the correct level for a TRUE 600 ohm load.

h. If any settings were changed to verify the AM-48 output, restore the AM-48 to provide the -10 dBm output into the transmitter.

16. Using the System Controller front panel, press the BACK button as necessary then the SELECT button until the Main Menu displays. Using the UP or DOWN buttons, align the arrow (>) with Control, then press the SELECT button. Use UP or DOWN and SELECT

6/4/13 A-22

Set Active TX, then use UP or DOWN and SELECT TXA or TXB to turn ON the transmitter that had been broadcasting.

17. On the System Controller panel, push in the RF ON switch. The green LED on the RF ON switch will light, and either the Transmitter A (TXA) or Transmitter B (TXB) LED under Alarm/Status will light green.

18. Using a communications analyzer with an antenna on the input, measure and record (in Attachment E) the modulation on the digital display (4.5 kHz ±0.25) Verify the sine wave on the CRT is symmetrical and is not distorted.