October 29, 2002 International Loran Association Design and Test of the First Article Accufix 7500 Transmitter Presented by Mark Danieli

Need for New Transmitter Factors leading to decision for new transmitter Goals for new transmitter

Factors Leading To Decision For New Transmitter TTX not supportable in near term TTX/SSX do not support additional capabilities (i.e. IFM) Cost reduction associated with fewer personnel requirements Unmanned Stations Remote Control

Goals for New Transmitter Increase individual HCG output power through component improvements Modernize Control Console - TCS Make the number of DHCs variable and assignments flexible Future incorporation of IFM has minimal impact on system architecture Maximize commonality with existing USCG assemblies

Accufix 7500 Transmitter Overview

Improved Architecture Prime Power Distribution Unit Pulse Generator Assembly Switch Network Assembly Coupling Cabinet Assembly Transmitter Control Subsystem (TCS)

Prime Power Distribution Unit

Provides emergency shutdown, at the site and via remote control Configuration dependent on the number of HCGs in transmitter Each subsystem has a dedicated breaker

Pulse Generator Assembly

PGA consists of 4 HCGs Component modernization: –Fire detection module linked to TCS HCG Assembly –Power Supply Reengineering Card Cage / Circuit Boards Backplane PCB Module connections Increased Capacitance (Droop)

HCG Power Supply 6500 Series 7500 Series Control Logic Boards

Pulse Generator Assembly (Con’t) Megatron Charger Assembly –A4 Resistor Board –Connector Replacement Megatron Assembly –Oil filling Connector –Snubber Board Addition –Higher Power Diode –Connector Replacement

Switch Network Assembly

3 second switchover Switch modules interchangeable New lightning arrestor Redundant DHC and Antenna current feedbacks Service Life Extension Program (SLEP)

Coupling Cabinet Assembly

Total Redesign – symmetric Reduced footprint Modular Electrically a hybrid between the 6500 and the AN/FPN-64 Circuit breakers now used in place of fuses

Benefits Increased Output Power/higher efficiency Increased flexibility More robust ECD control Improved Timing Stability

Work In Progress Ongoing development Future software enhancements –Refined fail soft –Signal Quality Analyzer (SQA)

Factory System Acceptance Testing Performance Measurements Test and Demonstration Tasks

Transmitted Signal Performance Measurements Envelope Shape Measurements –Amplitude measurements for positive and negative phase-coded pulses RF Zero Crossing Measurements –Specifications relates more the timing accuracy of the output pulses rather than to phase accuracy Spectrum & Harmonics Measurements Power Input Measurements IAW COMDTINST M16562

Performance Measurements 32 HCG Cape RaceAccufix 7500 Wildwood Antenna Current715 AMPS680 AMPS P2P ECD VAR <.45  sec<.15  sec P2P Timing Error< 25 nsec< 10 nsec Phase Mod 2 nd 3 rd 4-12 ~150 nsec ~100 nsec ~50 nsec ~75 nsec ~50 nsec ~35 nsec Input65 kW59 kW

Test and Demonstration Tasks Single Rate Test Dual Rate Test HCG Failure Recovery Test Switch-over Test 120-Hour Burn-In Test

Summary 16 HCG Transmitter for USCG LSU –FSAT completed in October 02 –Installation completed in November HCG Transmitter for LORSTA George, WA –FSAT in December 02 –Installation in January HCG Transmitter for LORSTA Kodiak, AK –In process USCG Support