Specifications

19A705178
REV NO. TITLE
CONT ON SHEET
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11
ROCKWELL MODEM TEST
SPECIFICATION/PURCHASE PART DRAWING
CONT ON SHEET SH NO. FIRST MADE FOR
F. C. F. O.
MADE BY
R Sager
APPROVALS
DCB
M. R. P. D.
DIV OR DEPT.
19A705178
ISSUED
Nov. 19, 1986
11-18-86
LYNCHBURG
LOCATION
CONT ON SHEET
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11
REVISIONS
L30
PRINTS TO
TECHNICAL SPECIFICATIONS
Transmitter Carrier Frequencies
Function
Frequency
(Hz ±
0.01%)
V27 bis/ter Carrier 1800
V27FT Carrier 1800
2400/4800 bps Gearshift 1800
V29 Carrier 1700
V29FT Carrier 1700/1800*
V21 Channel 2:
Mark 1650
Space 1650
*Selectable carrier frequency
Tone Generation
Under control of the host processor. the R96FT can
generate voice band tones up to 4800 Hz with a resolution
of 0.15 Hz and an accuracy of 0.01%. Tones over 3000 Hz
are attenuated.
Signaling And Data Rates
Parameter Specification
Signaling Rate:
Data Rate:
2400 baud
9600 bps
7200 bps
4800 bps
Signaling Rate:
Data Rate:
1600 baud
4800 bps
Signaling Rate:
Data Rate:
Gearshift Data Rate:
1200 baud
2400 bps
2400/4800 bps
Signaling Rate:
Data Rate:
300 baud
300 bps
Data Encoding
At 2400 baud. the data stream is encoded per CCITT V.29.
At 9600 bps, the data stream is divided in groups of four-
bits (quadbits) forming a 16-point structure. At 7200 bps,
the data stream is divided into three bits (tribits) forming an
8-point structure. At 4800 bps. the data stream is divided
into two bits (dibits) forming a 4-point structure.
At 1600 baud, the 4800 bps data stream is encoded into
tribits per CCITT V.27 bis/ter.
At 1200 baud, the 2400 bps data stream encoded into dibits
per CCITT V.27 bis/ter.
For the Gearshift configuration, the signaling rate is 1200
baud. The 2400 bps data stream is encoded into dibits
forming a 4 point structure, and the 4800 bps data stream is
encoded into quadbits forming a l6-point structure. The
first 32 bauds of data are transmitted at 2400 bps and the
remaining message is transmitted at 4800 bps.
At 300 baud, the 300 bps data stream is encoded per
CCITT V.21 Channel 2 into a mark frequency of I650 Hz
and a space frequency of 1850 Hz
Equalizers
The R96FT provides equalization functions that improve
performance when operating over low quality lines.
Cable Equalizers
- Selectable compromise cable
equalizers in the receiver and transmitter are provided to
optimize performance over different lengths of non-loaded
cable of 0.4 mm diameter.
Link Equalizers
- Selectable compromise link cable
equalizers in the receiver optimize performance over
channels exhibiting severe amplitude and delay distortion.
Two standards are provided: U.S. survey long and Japanese
3-link.
Automatic Adaptive Equalizer
- An automatic adaptive T
equalizer is provided in the receiver circuit
Transmitted Data Spectrum
If the cable equalizer is no enabled the transmitter spectrum
is shaped by the following raised cosine filter functions:
1. 1200 Baud. Square root of 90 percent
2. 1600 Baud. Square root of 50 percent
3. 2400 Baud. Square root of 20 percent
The out-of-band transmitter power limitations meet those
specified by Part 68 of the FCC's rules, and typically
exceed the requirements of foreign telephone regulatory
bodies.