P-H_Electronicss_LA-400B_Manual操作说明书手册

P&H ElectronicsModel LA-400BLinear AmplifierINTRODUCTIONThis manual has been reproduced by James Lawrence,NA5RC,a LA-400B owner.Thereare some notes on page 6 not associated with the manual.Where liberties are taken,theyare so noted.GENERAL DESCRIPTIONThe Model LA-400B Linear Amplifier is a grounded grid amplifier employing pentodesconnected as high mu triodes.This circuit design makes possible a compact,medium poweramplifier.When used with a suitable exciter,this amplifier will deliver a high quality signal whether usedfor single sideband,amplitude modulation,frequency modulation,or CW.A variety of output impedances may be matched by the pi network output circuit;however,alow impedance load is recommended.The low impedance input circuit is untuned.Thisfeature simplifies multiband operation.A well-filtered power supply incorporating full wavemercury vapor rectifiers is employed.The cabinet housing this amplifier matches manypopular exciters.High quality components are used throughout.SPECIFICATIONSPower Rating400 Watts P.E.P.InputDrive Requirement20 Watts for maximum outputDriver Impedance52-72 Q(The driver should employ link coupling or othermeans for DC return.)Frequency Range75 thru 10 MetersOutput Impedance50-75 Q on all bandsMetering CircuitIndicates RF Voltage Input,Plate Current,and RF AmperesOutputTubes2 ea Type 816 Rectifiers4 ea Type 1625(modified)OPERATING INSTRUCTIONSPreliminary1.Connect the driver to the coax fitting at the rear of the unit marked RF Input using ashort length of coax.WARNING:Do not apply plate power without a suitable driver connection.2.Connect a 52-72 Q antenna or load to the coax connector marked RF Output locatednear the center of the rear deck.3.Provision for blocking bias from exciter on Rear Deck if desired (See Figure 1).4.Plug the line cord into any 105-125 volt 50/60 cycle A.C.source.5.Apply filament voltage and wait at least 60 seconds before any attempt is made toapply plate voltage.Manual Update by NA5RCPage 1 of6