RCA Trans Vista 100 User manual

Technical Manual
The CTC 49 Color Chassis

Trans Vista 100
Technical Manual
The CTC 49 Color Chassis
Prepared By
RCA Sales Corporation
A Subsidiary of RCA Corporation
Product Performance— Technical Training
600 North Sherman Drive
Indianapolis, Indiana 46201
Trademark(s) , ARegistered Marca(s) Registrada(s)
Copyright © 1970 by RCA Sales Corporation
All rights reserved. No part of the material protected by this copyright
may be reproduced or utilized in any form without written permission
from copyright owner.
Price $ 4.50
First Edition 7032
Punted in U.S A.

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CONTENTS
General Description 1
RF and IF System 7
The Video System 15
Horizontal Deflection 27
Vertical Deflection 35
First- Level Maintenance 43
Shop- Level Maintenance 57

1

FOREWORD
The CTC 49 chassis represents the first of a " new breed" of RCA
all- solid-state color television receivers. This is particularly true from
the standpoint of servicing. The extensive use of plug-in circuit modules,
eleven in all, a tuner which may be exchanged without the need for
realignment of the coupling circuit to the IF amplifier, a solid-state
high- voltage quadrupler, which essentially is another module, and the use
of plug-in transistors makes it possible to correct most failures with
very little servicing effort.
In the preparation of this manual less than the usual space was
devoted to circuit description for three reasons. First, some of the circuitry
bears a close resemblance to earlier RCA chassis. This is true of the
tuner, AFT, and horizontal deflection system, which are similar to their
counterparts in either the CTC 40 or CTC 47 chassis; and the
sound module which is almost identical to the one used in the CTC 41, 42,
and 43 chassis. Second, integrated circuits are used in the IF and
chroma circuits, and a stage- by- stage analysis of these systems has little
value to the service technician, since many active devices are packaged
in a single unit. Third, since most repairs can be accomplished most
readily by module replacement, rather than by replacement of a single
component, an intimate knowledge of the function of each part in a
module is not essential to the technician.
Complete schematic diagrams of the various circuits were used instead of
partial or simplified diagrams. This will allow the technician to identify
all components of a particular circuit without tracing the interconnecting
lines used in the complete instrument schematic which is bound in the
back of this manual. Whenever possible the location of components in the
diagrams located in the text is indicated; however, the complete
instrument schematic should be consulted to verify component locations
and intermodule connections.
Servicing information contained in this manual is divided into two chapters.
The first of these discusses techniques and procedures for rapid
servicing either in the home or the shop. The final chapter goes into greater
detail and considers those areas of servicing which require the
facilities and equipment normally found only in the service shop.

GENERAL
DESCRIPTION
The RCA CTC 49 chassis is a fourth- generation
solid-state color receiver, employing, for the first
time, plug-in modules for most of the essential
functions. The CTC 40 chassis, introduced in 1968,
is the first of the RCA solid-state color receivers;
however, a vacuum- tube high- voltage rectifier was
used in that instrument. Next in order of introduc-
tion was the RCA CTC 47 chassis ( the G-2000),
which was released in 1969. This instrument re-
tained most of the circuits used in the CTC 40, but
several significant changes were incorporated in
its design. The electronically tuned VHF tuner and
signal- seeking UHF tuner of the CTC 47 are im-
portant advances in the state of the electronic
art, and because of their spectacular perform-
ance they tend to overshadow two other important
advances. These are solid-state high- voltage rec-
tification, using a voltage quadrupler, and motor-
less remote control, of volume, tint, and color.
The RCA CTC 44 chassis represents the third gen-
eration of solid-state color receivers and corn-
prises many of the basic circuit configurations of
the CTC 40, upgraded in many respects, plus the
high- voltage quadrupler and motorless remote
control of volume, tint, and color, from the CTC 47.
The CTC 49 is a natural outgrowth of these prede-
cessors; however a number of radical changes
have been made. Two of these are perhaps equal-
ly significant. These are modular construction, and
the extensive use of integrated circuits. Other ad-
vances include active side- pincushion correction,
transformerless vertical output, matrixing of the
color- difference and luminance signals before they
are fed to the kinescope, significant changes in the
convergence circuits, and a 110 color kinescope.
These will be described in this book, but before
proceeding to circuit descriptions, an overall
examination of the chassis is in order.
Figure 1-1 is a block diagram of the RCA CTC 49
chassis. A total of eleven plug-in modules is
used; a brief description of each module follows:
1

UHF
ANTENNA
—11e.
VHF
ANTENNA
UHF
TUNER
VHF
TUNER
4.5- MHz
SOUND IF
AF T
kT
MODULE MAH
HORIZ AFC
HORIZ OSC
HORIZ
TRIGGER
MODULE PM 200
SOUND DETECTOR
AUDIO PREAMP
MODULE MAK
SIGNAL I PIX IF
AGC
AGC AFT
VIDEO PREAMP
BLACK AND WHITE
VIDEO
SYNC
MODULE MAG
VERT SWITCH
VERT PREDRIVER
VERT DRIVER
SWEEP AND H. V.
REGULATOR
0401-T402
MODULE MAB
LOW- VOLTAGE
RECTIFIERS
AUDIO DRIVER
AUDIO 0 301
AUDIO OUTPUT
0103
il CH MODULE MAC
CHROMA ROMA BANDPASS
REFERENCE OSC
ACC
AFPC
1
MODULE MAL
FIRST VIDEO AMP
SECOND VIDEO AMP
SYNC SEPARATOR
VERTICAL
fie
VERTICAL OUTPUT
Q101-0102
SIDE PIN CORRECTION
HORIZ DEFLECTION
SCR 101- SCR 102
FLYBACK XFMR
KINE SCREEN SUPPLY
11*- 1- 220 ( VIDEO)
+160 ( HORIZ)
+77 ( VERT)
m- + 30 ( AUDIO)
a.. + 30 ( DIST)
B- W
VIDEO
YOKE
CURRENT
PHUOLRSIEZ
CHROMA
MODULE MAE
3 58 REF ICHROMA DEMODS
R- Y
BY
G Y
MODULES MAD
3 ARE USED— ONE
FOR EACH COLOR
COLOR VIDEO OUTPUT
AMPLIFIERS
CONVERGENCE
BOARD
RETRACE H.V. QUADRUPLER
PULSE
FOCUS BLEEDER
CONVERGENCE
BOARD PW 800 1 AGC GATE
in. BURST GATE
HORIZ AFC
PW 800
YOKE CURRENT
SPEAKER
RED VIDEO
BLUE VIDEO KINESCOPE
GREEN VIDEO I CATHODES
CONVERGENCE
ASSEMBLY
YOKE CURRENT
• Ile. VERT YOKE
SIDE
PINCUSHION
AMP
HIGH VOLTAGE
FOCUS VOLTAGE
SCREEN VOLTAGE
KINE SCOPE
HORIZ YOKE
Figure 1-1 Functional Diagram of the RCA CTC 49