Hoffman-Radio-Corp-118 电路原理图.pdf

MANUAL OF 1948 MOST-OFTEN-NEEDED RADIO DIAGRAMS MODEL B400 fuffman . A R A D I O CORP. CHASSIS 118 speaker voice coil; set RADIO CORP. I. F. ALIGNMENT: 1. Connect output meter across meter on 2.5 volt scale. 2. Connect output of signal generator directly to antenna post on loop; connect ground side of generator to chassis of receiver through .1 Mfd. condenser. Set signal genera tor on 455 Kc (modulated). 3. Adjust I.F. trimmers (first T4 and then T3) for maximum reading on output meter. R.F. ALIGNMENT: 1. Set tuning condenser with plates completely out. 2. Set signal generator at 1650 Kc (modulated) and feed its output into a loop of wire about 6 in diameter. Place this loop about one foot away from and parallel to the receiver loop antenna. 3. Tune in signal by adjusting oscillator trimmer (C4). 4. Adjust output of signal generator to obtain deflection on lower half of meter scale. 5. Adjust oscillator trimmer (C4) for maximum output. 6. Set signal generator at 1400 Kc and tune in signal with tuning condenser. 7. Adjust antenna trimmer (C3) while rocking gang con denser for maximum reading on output meter. Feed oniy enough signal from generator to keep maximum reading on lower half of meter scale. PIN NO. 1 2 3 4 5 -1 6 7 8 12SA7 0 24 A.C. +85 +92 5.5 0 11.5 A.C. .4 12SG7 0 22 A.C. 0 .4 0 + 92 36 A.C. + 86 12SQ7 0 -.8 0 0 1.0 +60 0 9 A.C. 50L6 0 36 A.C. + 101 + 93 +.2 0 87 A.C. +7.5 35Z5 0 117 A.C. 114 A.C. + 112 114 A.C. 0 87 A.C. + 116 DC voltages measured with 20,000 ohm/volt meter. NOTE: The above readings are obtained with no signal A.C. voltages measured with 1,000 ohm/volt meter. input to the receiver, radio-phono switch in the RADIO Ail voltages measured with reference to B. position, and volume control full on. 收音机爱 好者资料库 RadioFans.CN