MODEL DG535 Digital Delay / Pulse Generator - SLAC

amplitude is 100 mV, the maximum amplitudeis 4.00 VDC, and outputs outside the range of -3to +4 VDC are not allowed.AB and CD OUTPUTSThe menus for the AB and CD outputs aresimilar to the other outputs. Example menus forthe AB output are shown on the following page:AB&-AB Loads = High ZAB: TTL NIM ECL VARAB:Amplitude = +1.00V (if VARiable isselected)AB:Offset= +0.50V (if VARiable is selected)The cursor (up/down) keys select the loadimpedance for both the AB and -AB outputs. Itis very important that if a 50Ω load is specified,that a 50Ω load be present on BOTH the ABand the -AB output BNC's.The cursor (left/right) keys select the logiclevels for the AB and -AB outputs. If TTL, NIMor ECL is selected, then no further submenus areneeded to specify the outputs: both the"Normal" and "Inverted" logic levels areavailable at separate front panel BNC's. If VARis selected, then the next two submenus are usedto set the amplitude and offset of the outputs.GPIB MENUSThere are three menus which are accessed by theGPIB key. They are:Data:_______________GPIB Address: 15Service RQST: (EXC)The first menu displays the last 15 characters of datathat have been received over the GPIB. 256characters are retained in memory and may beviewed by scrolling the display window with thecursor keys. Spaces and control codes will not bedisplayed, however special characters for carriagereturns and line feeds will be displayed. This featureis very useful when debugging computer programsthat control the DG535.The GPIB address may be set in the second menu.The keypad is automatically placed in the numericmode for this menu item. Any address from 1 to 30may be entered: the default address for thisinstrument is 15.The third menu allows the user to generate a servicerequest by pressing the EXC button (lower right onthe front panel). A service request is used to attractthe attention of the GPIB controller.6