Belmont-Radio-Corp-A-5D118 电路原理图.pdf

MANUAL OF 1949 MOST-OFTEN-NEEDED RADIO DIAGRAMS 12SA7 12SK7 12SQ7 50L6GT CONVERTER I. F. AMP. 2ND DET. A.V. C OUTPUT & 1ST AUDIO ALIGNMENT PROCEDURE Volume controlMaximum all adjustments. Connect Bof radio chassis (12SQ7-Pin 3) to ground post of signal generator through ,1 Mfd. condenser. SIGNAL GENERATOR POSITION OF IRON CORES (Dial Setting) ADJUST TRIMMERS TO MAXIMUM (in order shown) Frequency Setting Dummy Antenna Connection to Radio 455 Kc. .1 MFD. Connect to Metal Antenna Backplate Iron Cores All the way out Trimmers on output and input I. F. cans 1720 Kc. .1 MFD. Connect to Metal Antenna Backplate Iron Cores All the way out Osc. Trimmer (C6) (See voltage chart) 1720 Kc. 200 MMF. Connect to Outside Antenna Clip Iron Cores All the way out Ant. Trimmer (C3) (See voltage chart) 1400 Kc. Connect to Outside Antenna Clip Turn Dial to 1400 Kc. Adjust position of antenna coil (See coil assembly view) 1720 Kc. 200 MMF. Connect to Outside Antenna Clip Turn Dial to 1720 Kc. ! Adjust trimmer (C3) (See voltage chart) NOTE A”The antenna coil assembly is made so that it is movable. When making the adjustment as given in the alignment procedure move the coil assembly very slowly. It can be moved by hand or by pivoting one edge of the blade of a screwdriver in the hole and engaging the blade in the gear teeth of the coil form. NOTE B”After the antenna coil has been tracked at 1400 Kc. it is necessary to check the antenna trimmer (C3) adjustment again at 1720 Kc. If no appreciable change in trimmer adjustment is made the coil is in track. If the trimmer requires considerable change it will be necessary to again adjust the position of the antenna coil at 1400 Kc. These two adjustments should be tried several times until no change of trimmer adjustment is required at 1720 Kc. Tiiwiwr Coil Assembly View MODEL A-5D118 收音机爱 好者资料库 RadioFans.CN