Motorola-VT-71-TS-4B-J-early-Sams-55-16电路原理图.pdf

PHOTOFACT* Folder MOTOROLA MODEL VT71 VOL.CONT. ON-OFF SWITCHFINE TUNING CHANNEL SELECTORCONTRAST CONT. MOTOROLA MODEL VT71 TRADE NAME Motorola, Model VT71 MANUFACTURER Motorola, Inc., 4545 Augusta Blvd., Chicago, 111. TYPE SET Television Receiver TUBES Sixteen POWER SUPPLY 115 Volts, 60 Cycle AC RATING 115 Volts TUNING RANGE- Channels 2 through 13 .96 Amps. TABLE OF CONTENTS Schematic Chassis Top View Parts List and Description Alignment Instructions Chassis Bottom View-Trans.,Inductor V. Rect. Cabinet Rear View 15 18 19 19 19 II 0 H HOWARD W. SAMS . INF. INF. 2 46CK2* 700KS2* Pin 2 10002* 33K2 332 INF. 10002* oa 822* 6.8K2 440K2* 308 1 Meg.* 17K2* sona* INF. 272 INF. 7, 4 02 INF . Pin 3 262 2.7K2 22S2 18B 14ffl 102 27S! sa 02 2302* OS 2102 OS! 3002 INF. 5 INF. I Pin 4 232 222 182 142 102 52 302 22 8,3 Meg. 3.3 Mee. 02* 10KS2* 150K2* 10 Meg. 3352* INF. 6 7 NF. IF-F. Pin 5 12002* 222 INF . * 6K2* 12002* 12K2* 12002* 1 Meg. 7.2 Meg. 2.5 Meei 470K2 7K2* 150K2* INF. 150K2 INF. 6 I:;F. i Pin 6 12002* 12002* INF.* 12002* 12002* 4.8K2* 12002* 470K2 02 INF. 02* 3.3K2 02 02 INF. , 9 10 NF . INF Pin 7 10002* lOKffi 332 INF. 10002* 02 822* 1 Meg. 112 402 22 112 272 362 INF. 11 INF. I Pin 8 - .32 - _ _ _ _ 22 3302 2.52 202 252 1002 INF. 12 13 NF . INF Pin? - 23a - _ _ _ _ - - - _ _ _ TOP CAP 12002* 14 22 TOO NOT MEASURE. CAN NOT MAKE ACCURATE MEASI1REFENT DUE TO HIGH IMPEDANCE OF CIRCUIT. TAKN WITH VACUUM TUBE VOLTMETER. MEASURED FROM JUNCTION OF M2 AND PIN 4 OF MS. MEASURED FROM POSITIVE TERMINAL 01 C-3B. 1 - DC Voltage measurements are at 20,000 ohms per volt; AC Voltages measured at 1000 ofims. 2 - Socket connections are shown as bottom views. 3 - Measured values are from socket pin to common negative unless otherwise stated. 4 - Line voltage maintained at 117 volts for voltage readings. 5 - Front panels controls set at maximum. 6 - where readings roay vary according to the setting of the service controls, both minimum and maximum readings are given. RadioFans.CN g m 005 HDR.HOLD 500 MMF A PHOTOFACT STANDARD NOTATION SCHEMATIC Howard W. Sams & Co., Inc. 1949 RadioFans.CN DISASSEMBLY INSTRUCTIONS 1. Remove 4 screws holding back panel and power Interlock and remove. 2. Remove push on type knobs and 2 felt washers on front of receiver. 3. Unplug speaker leads. 4. Remove picture tube socket. 5. Remove 4 chassis bolts from bottom of cabinet. 5. Slide chassis out rear of cab. 7. Remove-4 nuts and lock washers on speaker and remove. POSITIONING OF FEEDBACK SPRING ON H.V. RECTIFIER Feedback to the grid of H. V. Oscillator tube Is obtained by a capacltlve coupling device . consisting of a coll mounted around the envelope of the High Voltage Rectifier tube. The posi- tion of this spring Is very critical and misplacement will result In very low or no high volt- age. For the old construction tube (8016) the lower edge of the spring should be 13/16 1/32 from the top of the tube base. On the new type construction (1B3GT), the bottom edge of the spring should be 3/4 t 1/32 from the top of the tube base. 300 FOCUS HORIZ. CENT. VERT. HORIZ. VERT. HORIZ. VERT CENT. SIZE SIZE HOLD HOLD BRIGHTNESS CABINET-REAR VIEW PAGE 19 RadioFans.CN