RCA-Victor-Co-Inc-59AV1 电路原理图.pdf

MANUAL OF 1946 MOST POPULAR SERVICE DIAGRAMS Cathode-Ray Alignment is the preferable method. Connections for the oscillograph are shown in the schematic diagram. Output Meter Alignment.If this method is used, connect the meter across the voice coil, and turn the receiver volume control to maximum. Test-Oscillator.For all alignment operations, connect the low side of the test-oscillator to the receiver chassis, and keep the oscillator out put as low as possible to avoid a-v-c action. Calibration Scale.The glass tuning dial may be easily removed from the cabinet and temporarily attached to the chassis for quick reference during alignment. In the event that only the chassis is returned for service, and the cabinet with its tuning dial is left in the customers home, the full size calibration scale printed in this service note can be used for reference. Using Tuning Dial. 1. Remove the dial glass from the cabinet. 2. With gang at full mesh the pointer should be set to a point (1/16) inch to the left of the reference mark at the left hand end of the dial backing plate. 3. Place the glass dial under the pointer so that the extreme left scale graduations coincide with the pointer. Use scotch tape to hold the glass dial in place. Using Dial Scale Printed In This Service Note. Follow the procedure above, substituting the dial scale printed in this service note for the glass dial in the cabinet. “CH Band Reception.For best reception on “CM band with an outside antenna, adjust the trimmer screw of C4 on the antenna coil. Turn screw carefully with an insulated screwdriver (RCA Stock No. 31031) while the receiver is tuned to a station in the 31-meter band. If returning to internal antenna at any time, close the link on the center terminal and readjust ”C” band antenna trimmer (C4) for best reception on 31-meter band. Tune test osc. to Connect high side of test osc. to I-F grid in series with .01 mfd. 1st Det. grid in series with .01 mfd. 3 Yellow loop lead 1,500 kc - in series with - 200 mmf. 4 (link closed) 600 kc Adjust the follow- Turn radio ing for maximum dial to peak output “A” Band 540 kc “A” Band 1,500 kc “A” Band 600 kc L12, Lll (2nd I-F Trans.) L10, L9 (1st I-F Trans.) Repeat steps 3 and 4 Aut. terminal in series with 47 mmf. (link closed) “B” Band 6.1 me “C Band 15.2 me “C” Band 9.5 me C8 (osc.)* C2 (ant.) C7 (osc.)* C6 (ant.) Repeat steps 7 and 8 Install and connect chassis in cabinet, with link closed. Tune in a radiated oscillator signal at 1,500 kc and peak the “A” band ant. trimmer C3 (on loop). Rock in L8 for peak output at 600 kc. Use minimum capacity peak if two peaks can be obtained. Oscillator tracks 455 kc above signal on all bands. RECORD T0RA8E COMPARTMENT Critical Lead Dress 1. Push button, R.F. and oscillator leads should be separated as much as possibte to reducqdegenertion on push button reception. t2. R*F. choke in plate.circuit of 69G7 should be dressed towards the back apron. * * 3. Dress green push button lead under clamp and away from “C band series capacitor. 4. Dress heater leads away from grids and diodes. 5. Dress phono, cables up and away from all wiring. 6. Dress all excess leads from transformer back towards transformer. 7. Keep output plate leads short and dressed close to chassis. 8. Dress green lead from 6SA7 screen to electrolytic down close to chassis. 9. Dress “C” band coil lead from oscillator coil to range switch down toward green lead. 10. Keep yellow loop lead clear of all wiring. 11. Dress ground bus of large electrolytic away from mounting lug. 12. Remove all excess slack from pilot light assembly and dress it close to chassis base away from volume control. 13. Dress oscillator grid capacitor (56 mmfd.) up and away from the screen and plate of 6SA7 socket. 14. A-C leads to “off-on switch should be kept away from tone control cable to reduce hum. 15. Peaking coil should be dressed away from R-F grid resistor to reduce degeneration in R-F stage. 16. Dress oscillator push button lead in weld clamp on front apron away from 220 mmf. series condenser. 17. Keep all leads away from Phono.-FM jack to prevent audio oscillation and hum. Dress underneath the shield provided. Push Button Adjustment 680 TO 1600 HC TRIMMER SCREWS 0 I 0 The push buttons connect to separate magnetite-core oscillator coils and separate loop circuit trimmers which must be adjusted for the desired stations. Use an insulated screwdriver or alignment tool such as RCA Stock No. 31031. Allow about five minutes warm-up period before making adjustments. The procedure is as follows: 1. Make a list of the desired stations, arranged in order from low to high frequencies. 2. Turn the range switch to the broadcast position and manually tune in the first station on the list. 3. Turn range switch to push-button position and press in the left-hand button. 4. Adjust core rod No. 1 to receive the first station. To secure the best adjustment, rotate the loop for least pickup, and adjust core rod No. 1 for peak output. 5. Adjust trimmer screw No. 1 for peak output on the first station. 6. Proceed in the same manner to adjust for the remaining stations. 7. Repeat adjustments for best results. On the 880 to 1,600 kc push-button, the higher frequency stations may be received with core rod No. 6 either in or out (oscillator frequency either 455 kc below or 455 kc above the station frequency). The adjustment with this core in its out position (oscillator frequency 455 kc above the station frequency) is the correct one. NOTE: Clockwise adjustment of cores and trimmers tunes the circuits to lower frequencies. SERVICE HINT:If unable to reach 550-540 KC on No. 1 push button Connect a Stock No. 33111 Capacitor-Ceramic-33 mmf across L19 (between switch contact which connects to high side of L19, and switch frame). C7-COSC c*nt. ca-e otc mc (6SA7) * P UC43j Ul-W U2-EOTTW / 4SEKC VICTROLA 59V1, 59AV1 |UU|(g) rjgrj PnOho Radio-Phonograph Combination * J . O X X. TL t-.J 0115 1 ROWER CORPUS. JAC* Chassis No. RC 605 COMPILED BY M. N. BEITMAN, SUPREME PUBLICATIONS 103 收音机爱 好者资料库 RadioFans.CN MANUAL OF K UJ I 5 002 |2 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN