Table of Contents
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1.1.
HOW TO USE THIS MANUAL
4015
1.2.
DEFINITIONS
OVERVIEW
This manual is organized into 9 chapters : Overview, Installation, Operation,
Optional Software System Diagnostics, Technical Description, Connector Pinouts
& Cable Diagrams, Keykode Reader Installations and Film Emulsion Codes
If you are currently an owner of the Evertz 4015 Film footage Encoder, you will find
that much of the installation is similar for the 4025. Items that are of particular not
for 4015 users are marked with the following symbol in the margin.
Items of special note for all users are marked with a double box like this.
LINEAR TIME CODE: (Also known as Longitudinal Time Code) A digital code
used for timing and control purposes on video tape and associated
audio tape machines. It is recorded on a linear track with audio
characteristics and is referred to as LTC. Each 80 bit code word is
associated with one television frame, and consists of 26 time bits, 6
flag bits, 32 user bits and 16 sync bits.
VERTICAL INTERVAL TIME CODE: A digital code used for timing and control
purposes on video tape which is recorded in the vertical blanking
interval of the video picture, and is referred to as VITC. Each 90 bit
code word is associated with one television field, and consists of 26
time bits, 6 flag bits, 32 user bits, 18 sync bits, and an 8 bit error check
(CRC) code.
USER BITS: 32 bits in the time code are user assignable. They typically are used
to contain reel numbers, scene and take numbers, or other user-
oriented data. The 4025 Film Footage Encoder can be used to put
film footage and frame numbers into the user bits during the transfer
process from film to video.
DROP FRAME: In NTSC systems, where the frame rate is 29.97002618 frames
per second, the drop frame mode permits time of day indexing of the
frame numbers by dropping certain frame numbers.
frames 0, and 1 at the beginning of each minute except minutes
0,10,20,30,40, & 50, are omitted, to compensate for an approximate
timing error of 108 frames (3 seconds 18 frames) per hour. A flag bit
is set in the time code to signal when the drop frame mode is in effect.
JAM SYNC: Refers to the operation of slaving the generator to data coming from
the reader. Jam sync should be used when dubbing time code from
one tape to another, as the quality of the time code signal deteriorates
with each generation, and will become unusable after the third
generation.
In the jam sync mode, the generator and reader times are compared
with each other during each frame, automatically compensating for the
decoding offsets. If for any reason they are not equal, the jam is
Model 4025 Film Footage Encoder Manual
Specifically,
Page 1-4
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