《Emerson-Radio-and-Phonograph-Corp-FU427 电路原理图.pdf》由会员分享,可在线阅读,更多相关《Emerson-Radio-and-Phonograph-Corp-FU427 电路原理图.pdf(3页珍藏版)》请在收音机爱好者资料库上搜索。
1、MANUAL OF 1942 MOST POPULAR SERVICE DIAGRAMS EMERSON RADIO MODELS: FU-424, FU-427 and FU-428 LEAD FOR EXTERNAL ANTENNA IF PEAKED AT 262 K C * iMRfnT CIO IS COMPOSEO OF TWO PARTS, A FIXED CONDENSER AND TRIMMER,_ OUTPUT SECTION OUTPUT transforme DN SPEAKER RECTIFIER SECTION FILTER 11 7 P 7 CHOKE FEMAL
2、E & RECEPTACLE y- I I / T0 B / BATTERIES vim IvaUaf Q VOLTS Rl R2 R3 R4 R5 R6 R7, R8 R9 RIO Rll, R12, ) R14, R15 J R13 R16 R17 Cl, C2, C3 C4, C5, C6 C7 C8, C9, CIO Cll, C12, ) C16, C17 ) C13, C23, C25 C14, C18, C2e C15 C16, C17 C19 C20 C21 C22 C24 C26 C27, C28 C29 C30 i- LINE SWITCH ON - VOLUME CONT
3、ROL_ 2 megohm M watt carbon resistor 200,000 ohm M watt carbon resistor 5 megohm *4 watt carbon resistor 30,000 ohm M watt carbon resistor 1,000 ohm M watt carbon resistor-. 47,000 ohm M watt carbon resistor 500,000 ohm watt carbon resistor 10 megohm M watt carbon resistor 4,000 ohm M watt carbon re
4、sistor 3 megohm M watt carbon resistor Volume control .5 megohm 1,200 ohm % watt carbon resistor 860 ohm % watt wire-wound resistor Three-gang variable condenser.- Part of variable condenser. Padder condenser - Trimmers, part of i-f transformers. 0.05 mf, 200 volt tubular condenser 0.002 mf, 600 vol
5、t condenser_ 0.25 mf, 100 volt tubular condenser 0.02 mf, 200 volt tubular condenser 0.05 mf, 200 volt tubular condenser 0.0004 mf, 600 volt tubular condenser 0.02 mf, 400 volt tubular condenser 0.01 mf, 400 volt tubular condenser 0.00006 mf, mica condenser.- 0.00011 mf, mica condenser- 0.25 mf, 100
6、 volt tubular condenser Dual 20 mf,( 150.,volt dry electrolytic 0.05 mf, 400 volt tubular condenser 40 mf, 25 volt dry electrolytic condenser battery switch ON VOLUME CONTROL Location of Coils and Trimmer Adjustments The oscillator coil is located beneath the chassis. The trim mer for the oscillator
7、 is on the middle section of the variable condenser. The interstage coil is the shielded coil located beneath the Its trimmer is on the front section of the variable con denser. The trimmer for the loop antenna is on the last section of the variable condenser (the section nearest the loop). The i-f
8、transformers are mounted on top of the chassis. The first i-f transformer is mounted next to the loop. The second i-f transformer is mounted next to the dial. The series padder is located between the variable condenser and the shielded 1N5 tube. Note: This receiver has an i-f of 262 kc. Swing variab
9、le condenser to minimum capacity position. Feed 262 kc to the grid of the 1A7 tube through a 0.01 mf condenser. Adjust the three i-f trimmers for maximum response. Set the dial pointer at 140. Feed 1400 kc from the signal generator into a loop of wire about one foot in diameter. Hold this radiating
10、loop approximately one foot away from and paral lel* to the receiver loop and advance the output of the signal * generator until a suitable deflection is obtained on the output meter. Adjust first the oscillator trimmer (middle section) then the interstage and loop trimmers for maximum response. Mov
11、e dial pointer to 60 and feed 600 kc into the radiating loop and edjust the series padding condenser (while rocking the variable condenser back and forth) for maximum response. Realign at 1400 kc. COMPILED BY M. N. BEITMAN, SUPREME PUBLICATIONS 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN