Park Air T6-TV VHF Transmitter User Documentation
Product Code: T6-D-USER-TV-EN Product Code Identification Number: 31-30T6TVEN/1 Version 1.1 Date of Issue: February 2016 Published By: Northrop Grumman Park Air Systems Ltd Northfields Market Deeping Peterborough PE6 8UE UK Telephone: From UK, 01778 345434 From outside UK, +44 1778 345434 Email sales@parkairsystems.com Web site: www.northropgrumman.com/ParkAir © Park Air Systems Ltd 2015 All rights reserved.
Foreword This user documentation gives the necessary information for a user to install and understand the operation of the radio supplied by Northrop Grumman. Copyright and trademarks This documentation could contain information provided by other equipment manufacturers. It is acknowledged that the copyright of any third party information is retained by the respective holder.
Health and safety Disposal This equipment is covered by the European Directive 2012/19/EU. Items must not be disposed of in domestic waste. Disposal must be made using designated collection facilities appointed by the government or the local authorities in your area. RoHS Directive 2011/65/EU compliant. Warnings A warning is used to show possible danger to personnel.
Dangerous voltage You must be suitably qualified to terminate a mains supply to the equipment. Antenna radiation The transmit antenna must be installed such that the resultant radiated field strength is below national limits, see “Annex” for limits and examples. The safe distance must be calculated for each installation. No user serviceable parts inside the radio There are no user serviceable parts inside the radio. Access to the fan is from the rear of the radio.
Park Air Services Use email, telephone or fax to contact Park Air Services. For help with configuration, installation or maintenance of equipment, use any of the contact methods listed below. Email: support@parkairsystems.com Telephone (24 hours): Within the UK, International, 01778 381557 +44 1778 381557 Mail: Customer Services Department Northrop Grumman Park Air Systems Ltd Northfields Market Deeping Peterborough PE6 8UE UK Web Site: www.northropgrummaninternational.
Approvals and standards Approvals CE R&TTE Directive 1999/5/EC/RED 2014/53/EU Standards T6-D-USER-TV-EN © Park Air Systems Ltd 2015 EMC EMC EN 301 489-22 v1.3.1 2003-11 Safety BS EN 60950-1:2010 AM Voice EN 300 676-1 v1.5.
CE type approval ĞĐůĂƌĂƚŝŽŶ ŽĨ ĐŽŶĨŽƌŵŝƚLJ ŽŵƉĂŶLJ ŝŶĨŽƌŵĂƚŝŽŶ WĂƌŬ ŝƌ ^LJƐƚĞŵƐ >ŝŵŝƚĞĚ ;Ă ǁŚŽůůLJ ŽǁŶĞĚ ƐƵďƐŝĚŝĂƌLJ ŽĨ EŽƌƚŚƌŽƉ 'ƌƵŵŵĂŶ ŽƌƉŽƌĂƚŝŽŶͿ EŽƌƚŚĨŝĞůĚƐ͕ DĂƌŬĞƚ ĞĞƉŝŶŐ͕ WĞƚĞƌďŽƌŽƵŐŚ͕ W ϲ ϴh нϰϰ ϭϳϳϴ ϯϰϱ ϰϯϰ WƌŽĚƵĐƚ͕ ŵŽĚĞů ĂŶĚ ĚĞƐĐƌŝƉƚŝŽŶ W Z< /Z dϲ dϲ Ͳds 'ƌŽƵŶĚ ƚŽ Ăŝƌ ƚƌĂŶƐŵŝƚƚĞƌ ĨŽƌ ƵƐĞ ŝŶ ƚŚĞ s,& ĂĞƌŽŶĂƵƚŝĐĂů ďĂŶĚ ƵƐŝŶŐ Ϯϱͬϴ͘ϯϯŬ,nj ĐŚĂŶŶĞů ƐƉĂĐŝŶŐ ^ƚĂŶĚĂƌĚƐ EϲϬϵϱϬͲϭ ;ϮϬϬϲн ϭ͗ϮϬϭϬ͕ ŝŶĐŽƌƉŽƌĂƚŝŶŐ ĂŵĞŶĚŵĞŶƚ ϭϭ͗ϮϬϬϵͿ EϯϬϭ ϰϴϵͲϮϮ ;sϭ͘ϯ͘ϭ ϮϬϬϯͲϭϭͿ EϲϮϯϭϭ ;ϮϬϬϴͿ EϯϬϬ ϲϳϲͲ
About this user documentation This user documentation has eight sections: Section 1. Overview Section 2. Description - the human machine interface and detailed connectivity Section 3. Installation - standalone, the Park Air C4 cabinet and legacy T6 cabinet Section 4. Operation - how to use the Park Air T6-TV Section 5. Maintenance - periodic tasks and part replacement Section 6. Connector information - interface types and levels Section 7. Specification Section 8.
Glossary of abbreviations, acronyms and technical terms A Ampere AC alternating current ACARS aircraft communications addressing and reporting system Active The radio is operationally active (IP RRC terminology) AGC automatic gain control ALC automatic level control AM amplitude modulation ATC air traffic control ATM air traffic management baud symbol rate or modulation rate in symbols per second or pulses per second BIT built-in-test co-location A location with multiple radio channel
Glossary of abbreviations, acronyms and technical terms (continued) Off-air standard An extremely high stability RF frequency source, for example GPS OLED organic light emitting diode Ohm unit of resistance Phantom PTT DC control voltage applied to transmit audio input lines Phantom Squelch DC control voltage applied to receive audio output lines pk-pk peak to peak ppm parts per million PTT press-to-transmit or push-to-talk RF radio frequency RJ45 8 position 8 contact (8P8C) connector RCMS
Park Air Sapphire The Sapphire concept builds on almost 50 years of Park Air innovation, delivering a truly integrated approach to providing ground-to-air solutions. The aim of Sapphire is to optimise the customer’s experience. The result is a coherent and unified collection of system components, backed up by a tailored suite of support services. From radios, controllers and filters to headsets and antennas, the Sapphire portfolio includes everything required for ATC communication systems.
1 Overview 1.1 Introduction The Park Air T6-TV VHF transmitter is a class-leading analogue and IP, ACARS, voice and data radio, with the flexibility for any ATC scenario, integrated into a small light package. The Park Air T6-TV options: There are four frequency range options that extend from 112 to 155.975 MHz There are four maximum transmit power output options from 10 to 50 watts Software defined analogue and digital waveform options. The options are shown in 1.2.2 Park Air T6-TV options.
1.1.1 Standalone operation The Park Air T6-TV can be used as a standalone desktop radio with the addition of a suitable AC and/or DC supply, a VHF antenna and a microphone or headset. Park Air Sapphire products are: Park Air T6-A-CK Connector Kit Park Air S2 microphone Park Air S2 headset. Installation details are shown in 3.1 Park Air T6 standalone installation. 1.1.
1.2 Park Air T6-TV The product codes and product names of the radio, options, accessories and documentation for the T6-TV radio. 1.2.1 Park Air T6-TV product code Product code Product name T6-TV VHF transmitter Notes 1.2.
Intentionally Blank T6-D-USER-TV-EN © Park Air Systems Ltd 2015 Page 1-4 Overview
2 Description The T6-TV interfaces are shown in this section. 2.1 Front panel interfaces Busy indicators Rotary/push switch Display LAN 3 connector Reference frequency monitor connector Microphone/headset connector On/off switch Soft function keys Status indicator Loudspeaker Control Notes On/off switch Front panel on/off of the radio See 2.1.1 On/off switch Display Parameter fields and soft function icons See 2.1.2 Display Soft function keys See 2.1.
2.1.1 On/off switch Control Notes On/off switch The power cord is the power disconnect device. Note: This action symbol is used in the document. 2.1.2 Display This is a high resolution OLED display. 118.000 MHz Parameter fields AM Voice Note: In the example, two parameter fields are shown and one is blank. Up to three parameter fields can be shown or blank. The display brightness lessens after 24 hours. Soft function key icons 2.1.
2.1.4 Busy indicators Busy indicator Function Notes The radio transmits The busy indicator illuminates amber 2.1.5 Rotary/push switch Action Notes Adjust the rotary/push switch Changes selected volume setting. Changes the display menu Push the rotary/push switch Selects. Saves settings Note: These action symbols are used in the document. 2.1.6 Status indicator The Status indicator is around the rotary/push switch. Status indicator Action Notes Illuminates blue BIT status is Full Service.
2.2 Rear panel connectors DC input AUDIO connector ANTENNA connector LINK connector FAC (facilities) connector AMPLIFIER connector E1 connector AC input RF LINK connector FILTER connector LAN 1 connector LAN 2 connector Earth stud connector Each connector type is shown in the table below and associated connection cable colour codes.
2.2.1 VoIP connectivity There are two ED-137 Ethernet connection options LAN 1 and LAN 2, on the rear of the radio: Ethernet connection (LAN 2) Ethernet connection (LAN 1) Note: Each LAN connector has a unique MAC address. The radio connected to two digital voice communication and control systems (VCCS): VCCS 1 VCCS 2 Network LAN 1 connector LAN 2 connector* *Note: The two ports on the rear of the Radio radio are for redundant system interface connections.
2.2.2 E1 connectivity There is an E1 connection for digital radio systems, digitalised voice communication systems (VCCS) and RCMS: E1 connection 2.2.
2.2.4 Transmitter power amplifier connectivity There is an AMP (amplifier) connection on the rear of the radio, for use with the Park Air T6-AV power amplifier range: Transmit antenna Transmitter power amplifier RF output connector RF input connector AMP control Control connector 2.2.
2.2.7 AC and DC connectivity There are both AC and DC inputs. DC input and/or AC input 2.2.8 Antenna connectivity There are a number of standalone and main/standby antenna configurations. More information on antenna configurations can be found in 2.3 Antenna configurations. Standalone operation Main/standby operation Transmit Transmit Not used Standby transmit RF link* *Uses the T6-TV internal solid-state RF change-over.
2.3 Antenna configurations 2.3.1 Standalone configuration Transmit antenna 2.3.
2.4 Radio label The radio label is on the bottom of the radio. 2.4.1 Serial number label A serial number label is on the rear of the radio. 2.4.2 QR code The QR code includes the serial number.
3 Installation Dangerous voltage You must be suitably qualified to terminate a mains supply to the equipment. Antenna radiation The transmit antenna must be installed such that the resultant radiated field strength is below national limits, see “Annex” for limits and examples. The safe distance must be calculated for each installation. Earth connection This equipment must be earthed. The earth terminal of the AC connector must be used as the safety earth.
3.2 Park Air C4 cabinet installation 3.2.1 Tool-free installation Park Air C4 cabinet (front) Cabinet shelf Identify the required radio position Cabinet shelf Rear of radio Hold the radio with both hands Slide Rear of radio Slide the radio on the rear feet to the rear of the shelf Earth stud Cabinet shelf Rear feet Earth stud Cabinet shelf Slots Engage the rear feet into the slots Profiled holes Slide Rear of radio Slide the radio until the front feet locate in the profiled holes.
3.2.2 Connect the cables If the radio is fitted to a wired position in the cabinet, the radio control cables are wrapped together. (1) Connect the RJ45 cables as applicable. The cables are colour-coded. RJ45 cable colour Radio RJ45 connection Red AUDIO Orange LINK Yellow FAC Green AMP Blue E1 Purple FILTER Grey LAN 1 Grey LAN 2 (2) Connect the antenna cable. (3) Connect the AC and /or DC supply cables. The radio is fully connected.
3.3 Legacy Park Air T6 cabinet installation To fit a Park Air T6 radio to a Cooper B-Line cabinet, a mounting adaptor is to be used. 3.3.1 Legacy Park Air T6 cabinet accessories Product code Product name T6-A-CMA1 Cooper B-Line cabinet mounting adaptor for 1 or 2 T6 radios 3.3.2 Mounting adaptor installation To fit the mounting adaptor to a Cooper B-Line cabinet: (1) Identify the cabinet position where the radio is to be fitted.
4 Operation The easy-to-use menu-driven T6 radio has a clear, easy-to-read screen and icons. To help the user, the switch and soft key icons detailed in 2 Description are shown in the instruction steps. 4.1 Turn the radio on Make sure the radio is connected to an AC and/or DC supply Push The radio then initialises. (1) The icon illuminates (2) The display shows: PARK AIR T6 Initialising . . . The radio then shows the home screen. 4.1.1 Home screen An example of the Home screen: 118.
4.2 The screen menus 4.2.1 Settings These are the radio settings. To look in Settings: Select Scroll so that Settings is shown: Status Settings Information To enter the settings list: Push The settings list screen is shown. Volume Loudspeaker Freq 118.000 MHz Step 25 kHz (To view a different setting, scroll through the settings list.) To change a setting, the Frequency setting is shown as an example: Select Adjust or push If a cursor is displayed: Freq 118.
Settings Description Notes Default Volume Loudspeaker Loudspeaker/Headset volume Selection of loudspeaker or headset. Adjust the volume setting with the rotary/push switch Loudspeaker Freq 118.000 MHz Carrier frequency Example of carrier frequency Option minimum Freq Preset 1 Frequency Preset 1 to 100 Front panel frequency step size Selection of 8.3 kHz or 25 kHz steps 25 kHz Reference frequency 0 to 100% 50% Carrier offset 0 kHz, ±2.5 kHz, ±4 kHz, ±5 kHz, ±7.3 kHz, ±7.
4.2.2 Status This is the operational status of the radio. To look in Status: Select Scroll so that Status is shown. Status Settings To enter the status list: Push The status list screen is shown: Test FULL SERVICE Status Messages To view more status information/analogue measurements: Scroll To select a Status Message, Monitoring or Status Reset: Push Scroll as necessary.
Status Test FULL SERVICE Status Messages Description Notes Built-in test (BIT) See 4.3.1 How to do a BIT test from the front panel BIT system service level If the radio shows Full Service, there are no status messages Reduced and No Service status message/s: AC Supply DC Supply VSWR Ambient Temp System Amplifier E-BIT Fan Radio Health Only necessary messages (faults) are shown, see ETI ******h.
4.2.4 Information This is the information about the radio. To enter Information: Select Scroll so that Information is shown: Settings Information To enter the Information list: Push The Information list screen is shown. Model T6-TV 24-04365031/1 To view more information: Scroll To go back to the menu screen: Select To go back to the home screen: Select The information list is shown on page 4-7.
Screen Information Model T6-TV 24-04365031/1 Serial No.
4.3 How to guides 4.3.1 How to do a BIT test from the front panel Test is shown in the status list: Select Scroll so that Status is shown.
When the test is complete, the service level is shown: Status FULL SERVICE REDUCED SERVICE NO SERVICE Description The radio is operational to specification The radio is not fully operational and possibly does not meet specification The radio is not operational Note: The user can change a Reduced Service BIT monitored parameter to show NO SERVICE. See 4.3.2 How to set a radio configuration. 4.3.2 How to set a radio configuration A web server is hosted in the radio.
Intentionally Blank T6-D-USER-TV-EN © Park Air Systems Ltd 2015 Page 4-10 Operation
5 Maintenance No user serviceable parts inside the radio There are no user serviceable parts inside the radio. Double pole/neutral fusing The radio uses a power supply which has both live and neutral fuses. 5.1 Reference frequency adjustment In stable environmental conditions, adjustments are recommended (subject to local regulations) as follows: For 5-carrier offset operation - every 12 months For 2-carrier offset operation with 8.
5.2 Status message procedure The table shows Status messages, message descriptions and necessary actions.
Under revision Make sure that radio failure is not due to an external failure, for example, antenna circuit VSWR. If the internal fault condition is still displayed, return the radio to Northrop Grumman, see Park Air Services. Notes: A radio whose Service Status changes to No Service, automatically becomes Inactive. The faulty radio drops its SIP session in accordance with ED-137. Transmit operation is inhibited when the radio is Inactive. 5.3 Fan replacement To replace the fan: (1) Switch off the radio.
(5) Move the fan away from the rear panel. (6) Disconnect the fan connector. Clip-on connector Note: The radio is shown on its left-hand side (7) Check the heatsink cooling fins for blockages. (8) Connect the new fan. Note the cable and fan position: Cable position Fan markings Note: The radio is shown on its left-hand side (9) Place the fan in position on the rear panel. (10) Attach the fan with the four (4) fixing screws. (11) Install the radio to the cabinet (if applicable).
6 Connector information 6.1 Front panel connectors The front panel connector pin-outs: LAN 3 connector Connector 1 LAN 3 connector RJ45 Pin Signal 1 TD+ output 2 TD- output 3 RD+ input 4 Not used 5 Not used 6 RD- input 7 Not used 8 Not used Characteristics Balanced 100 ohm output, 10/100 Mbits per second. Balanced 100 ohm input, 10/100 Mbits per second. Balanced 100 ohm input, 10/100 Mbits per second. A valid link illuminates amber LED and flashing amber LED indicates activity.
6.2 Rear panel connectors The rear panel connector pin-outs: AUDIO connector Connector Pin Signal 1 Configuration Phantom PTT (if Enabled): STANDARD - normally open, closed on PTT (default). INVERTED - normally closed, open on PTT. The default for Phantom PTT is Disabled. Audio Line In - 1 2 Audio Line In + 3 Main/Standby Output Characteristics 600 ohm balanced, transformer coupled. Adjustable from -30 dBm to +10 dBm (±2 dB) in 1 dB steps, with the default setting -13 dBm.
FAC (facilities) connector Connector Pin 1 Signal Configuration STANDARD - normally open, closed when active (default). INVERTED - normally closed, open when active. Active/Inactive Characteristics Grounding output, 200 mA maximum. 1 2 3 Fixed 0 dBm ±2 dB for 90% modulation, 600 ohm output. TX/RX tape 4 FAC Ready output STANDARD - normally open, closed when BIT status not Full Service or when radio is inhibited (default).
E1 connector Connector Pin Signal Configuration 1 RRing input Balanced 120 ohm, 2.048 Mbits per second (±50 ppm), HDB3 Coding. 2 RTip input Protected with 28 V differential and common mode clamp and 1.25 A fuse in each line. 3 Not connected 4 TRing output 5 TTIP output 6 Remote on/off input 7 Ground (0 V) 8 Supply output 1 E1 Characteristics RJ45 A PTT Confirm CAS pattern can be enabled/disabled.Default is enabled. Balanced 120 ohm, 2.048 Mbits per second (±50 ppm), HDB3 Coding.
LAN 1 connector Connector Pin Signal TD+ output 2 TD- output 3 RD+ input 4 Not connected 5 Not connected 6 RD- input 7 Not connected 8 Not connected 1 1 LAN 1 RJ45 Characteristics Balanced 100 ohm output, 10/100 Mbits per second. Balanced 100 ohm input, 10/100 Mbits per second. Balanced 100 ohm input, 10/100 Mbits per second. A valid link illuminates amber LED and flashing amber LED indicates activity. 100 Mbits illuminates green LED , 10 Mbits off.
AC input connector Connector Connection Neutral Characteristics Input supply: 99 to 264 V AC. Frequency: 47 to 63 Hz. No more than 400 VA while the radio transmits under any condition. Earth Live Note: AC input The connections are shown as viewed on the rear panel of the radio. IEC-C14 chassis plug The cable used to connect between the equipment and the user’s AC power source must be 3-core (to IEC 227) rated 250 VAC at 8 amps, and have a minimum cross-sectional area of 1.0 mm2 per core.
ANTENNA connector Connector Connection The Antenna connector can be configured for: Transmit only. Note: Automatic power reduction in the presence of high VSWR can decrease the RF power to 5 W. ANTENNA N-type socket RF LINK connector Connector Connection The RF Link connector can be configured for: Transmit RF link.
Intentionally Blank T6-D-USER-TV-EN © Park Air Systems Ltd 2015 Page 6-8 Connector information
7 Specification 7.1 T6-TV specifications Parameter Operating frequencies Value 118 MHz to 137 MHz Extendable to between 112 MHz and 156 MHz Output Power 50 W maximum Dimensions 79 mm (2U) high 210 mm (half-rack) wide 420 mm deep Weight 5 kg Waveforms AM Voice with 25 kHz and 8.
7.
Feature Benefit Simplified installation, set-up and usability Half the size and weight of previous models More channels in available cabinet space No tools required for cabinet installation Intuitive user interface High resolution OLED graphical display Main rotary input control Context-specific soft buttons Indicator icons Visual indications of radio activity Loudspeaker to monitor voice transmissions T6-D-USER-TV-EN © Park Air Systems Ltd 2015 Page 7-3 Loudspeaker provided to monitor voice trans
Intentionally Blank T6-D-USER-TV-EN © Park Air Systems Ltd 2015 Page 7-4 Specification
8 Associated equipment 8.1 Table of associated equipment Product code Product name Notes A6-ATE6000 Confidence test equipment A portable automated RF communications test system used to provide confidence that Park Air radios and systems are functioning correctly. A6-O-T6S3RAD Radio test suite for use with T6 radios For use with A6-ATE6000 to allow confidence testing of T6 Radios. Includes radio test script and test interface adaptor including cables.
8.2 C4 cabinet specifications Capacity Height Width Depth 40 U 1989 mm 600 mm 675 mm 30 U 1544 mm 600 mm 675 mm 8.2.1 C4 cabinet fixing holes 569.0 72.0 535.0 12.
Park Air T6 Quick Start Guide Park Air T6 Quick Start Guide Warnings and cautions Front panel tour Busy indicators Rotary/push switch Dangerous voltage You must be suitably qualified to terminate a mains supply to the equipment.
Intentionally Blank Park Air T6 Quick Start Guide © Park Air Systems Ltd 2015 Intentionally Blank Version 1.1 Park Air T6 Quick Start Guide © Park Air Systems Ltd 2015 Version 1.
Index Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2 AC input . . . . . . . . . . . . . . . . . . . . . . . .2-4, 2-8 Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7 Analogue . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 Auto-tune cavity filter . . . . . . . . . . . . . . . . 2-7 DC input . . . . . . . . . . . . . . . . . . . . . . . .2-4, 2-8 E1 . . . . . . . . . . . . . . . . . . . . .
F J FAC connector . . . . . . . . . . . . . 2-4, 2-7, 3-3, 6-3 Facilities Connectivity . . . . . . . . . . . . . . . . . . . . . . . . 2-7 Connector . . . . . . . . . . . . . . . 2-4, 2-7, 3-3, 6-3 Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 Replacement . . . . . . . . . . . . . . . . . . . . . . . 5-3 Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1 Connectivity . . . . . . . . . . . .
O Rear panel connectors . . . . . . . . . . . . . .2-4, 6-2 Reduced service . . . . . . . . . . . . . . . 2-3, 4-5, 4-9 Reference frequency . . . . . . . . . . . . . . . . . . . 4-3 Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 Monitor connector . . . . . . . . . . . . 2-1, 5-1, 6-1 Relay Solid-state changeover . . . . . . . . . . . .2-9, 8-1 Remote on/off input . . . . . . . . . . . . . . . . . . . 6-4 RF LINK connector . . . . . . . . . . . . . . 2-4, 2-9, 6-7 RF power . . . . . . . .
T T6-AV power amplifier . . . . . . . . . . . . . . . . . 8-1 Connectivity . . . . . . . . . . . . . . . . . . . . . . . . 2-7 T6-TV Accessories . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 Documentation . . . . . . . . . . . . . . . . . . . . . 1-3 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 Product code . . . . . . . . . . . . . . . . . . . . . . . 1-3 Specifications . . . . . . . . . . . . . . . . . . . . . . . 7-1 Test Equipment . . . . . . . . . . . . . . . . . . . .
Annex Health and safety Antenna radiation Countries within the European Union The RF field strength limits according to EN 62311:2008 Assessment of electronic and electrical equipment related to human exposure restrictions for electromagnetic fields (0 Hz - 300 GHz), are shown in the table below: Frequency Occupational level 100 - 400 MHz 10 W/m General population level 2 2 W/m2 Example The safe distance from the antenna can be predicted using the equation: R = 1.
Canada The RF field strength limits according to Health Canada Safety Code 6, are shown in the table below: Frequency MHz Occupational level W/m2 General population level W/m2 112.000 6.83 1.29 118.000 7.01 1.29 127.500 7.28 1.29 136.975 7.55 1.29 155.975 8.06 1.29 225.000 9.68 1.29 300.000 11.18 0.13 399.975 12.90 0.15 The general equation for Occupational level: W/m2 = 0.6455 f 0.5 where, f = frequency in MHz.