t4225b ATMEL Corporation, t4225b Datasheet - Page 15

• Manufacturer Part Number: t4225b
• Description: Low-cost Time-code Receiver
• Manufacturer: ATMEL Corporation

Rev. A3, 03-Dec-98
Information on the Japanese Transmitter
Station: JG2AS
Frequency 40 kHz
Transmitting power 10 kW
Modulation
The carrier amplitude is 100% at the beginning of each
second and is switched off after 500 ms (binary one) or
after 800 ms (binary zero).
seconds
0
0.5 s
Example: 18.42 h
59
minutes
P0
“1”
5
0
1
Frame-reference marker (FRM)
Position-identifier marker P0
10
40 20 10
0.8 s
2
hours
“0”
15
3
4
20
minutes
5
Time frame 1 minute
8
(index count 1 second)
Time frame
“P”
25
0.2 s
6
da ys
4
7
2
30
Figure 26.
8
1 P1
0.5 second: Binary one
0.8 second: Binary zero
0.2 second: Identifier markers P0...P5
9 10 11 12 13 14 15 16 17 18 19 20
35
Location: Sanwa, Ibaraki
Geographical coordinates: 36 _ 11’ N, 139 _ 51’ E
Time of transmission: permanent
Time-Code Format
The time-code format consists of 1-minute time frames.
A time frame contains BCD-coded information of
minutes, hours and days. In addition, there are 6 position-
identifier markers (P0 thru P5) and 1 frame-reference
marker (FRM) with reduced carrier amplitude of 800 ms
duration.
code
Position identifier marker P1
40
dut1
45
20 10
50
hours
55
8
4
0
T4225B
2
Time frame
1
5
P2
93 7508 e
10
15 (16)