Decatur Electronics GHD User Manual

Also see for GHD: User manual

Contents

Decatur Electronics GHD User Manual Manual pdf 13 page image

GHD™ & Scout™ User’s ManualGHD™ & Scout™ User’s Manual2425/Aug/2010To switch from Strongest Signal target to Faster target, press andrelease the FAST button The speed of the vehicle returning thestrongest signal will continue to appear in the left window, and thespeed of the next strongest target going faster than the strongestwill appear in the right window The system will remain in Fastermode until you press the FAST button again or until you lock a speed,which automatically switches the gun back to the Strongest Signaltarget6. Serial Output ModeThe GHD and the SCOUT have an RS232 communications port onthe bottom of the handle Using a custom RS232 communicationscable, you can connect the radar and transmit data to display signs,in-car video, and PCs for recording and analyzing speed data Figure6 illustrates the location using the SCOUT as an exampleFigure 6Port location as shown on the SCOUT• In Faster-Toggle mode, the radar gun locks only thestrongest vehicle speed5.6 Faster-Hold ModeTo use Faster-Hold mode, make sure you have selected Faster-Holdin the menu (FSt 0) Press and continue to hold the FAST buttonWhen active, the faster vehicle speed is in the left window If thereare no faster vehicles, the display will be blank When you release theFAST button, the gun will automatically switch back to the strongestsignalIf you lock the speed of the fast vehicle, the LOCK and FAST icons willdesignate that the locked speed is a faster target lock If these iconsdo not appear, the lock is on the strongest targetFigure 5.6Strongest signal > Faster–Toggle > Faster–Hold7. Performance TipsUnderstanding potential radar interference and what to do when itoccurs can greatly increase the radar’s performance7.1 How Radar WorksDetermining a vehicle’s speed begins with the radar gun transmittinga beam of microwave energy (radio waves) at an approaching ordeparting target vehicle When energy from this beam strikes avehicle, a small amount of the beam is refected back to the antennaThe refected signal frequency shifts by an amount proportional tothe speed of the target vehicle This is known as the Doppler efectThe radar device then determines the target vehicle speed from thediference in frequency between the refected and transmitted signal7.2 Interference SourcesWhen properly installed and operated, Doppler radar technologyis accurate and reliable However, variations in the environmentcan cause situations and circumstances, which can cause spuriousresponses which are readily identifed by a qualifed operator Signsthat a speed is spurious can include the following characteristics:25/Aug/201025