Panasonic KX-TDA6181X, Руководство по обслуживанию, Страница: 20 / 71

7.2.4. Bell Signal Detection
During on-hook, transmitting the bell signal to the AC loop in the CR series circuits (C2 and R2) detects the current by Photo
Coupler (PC1,2), and it determines the presence of a bell signal. Software performs the operation for recognition and determination
of a pattern of bell signals.
Bell Loop Path:
• • • • Ring → L3 → L2 → RL1 → R50 → PC1(1-2) → C2 → R2 → J9 → RL1 → J3 → L1 → L4 → J7 → Tip
In this path, PC1 4-pin converts from High to Low, and a bell signal is detected.
• • • • Tip → J7 → L4 → L1 → J3 → RL1 → J9 → R2 → C2 → PC2(1-2) → R50 → RL1 → L2 → L3 → Ring
In this path, PC2 4-pin converts from High to Low, and a bell signal is detected.
7.2.5. DTMF Signal Detection
This is provided on the CALLER ID detection card (CID8) and CALLER ID/PAYTONE detection card (CID/PAY8) of the option
cards.
7.2.6. Polarity Reversal Detection
Configured by the photo couplers (PC1,PC2) which enables current detection in either the Tip → Ring or Ring → Tip directions.
(PC2 is used in common as the bell detection photo coupler). Using Software, it stores the current direction (the detected photo
coupler) of the connected trunk and adjusts the direction of the current flow detection. (the detected photo coupler changes).
When the current flows in the direction of Ring to Tip, PC1 4-pin is Low and PC2 4-pin is High.
• • • • Ring → L3 → L2 → RL1 → R50 → PC1(1-2) → J5 → D2 → PL2 → Q6(C-E) → R5 → R80 → D2 → RL1 → J3 → L1 → L4 → J7 → Tip
When the current direction (polarity) is reversed from Tip to Ring, PC1 4-pin turns to High and PC2 4-pin turns to Low. It recognizes
the action by changing of the current direction (the detected photo coupler changes).
•
• •
•
Tip
→
J7
→
L4
→
L1
→
J3
→
RL1
→
D2
→
PL2
→
Q6(C-E)
→
R5
→
R80
→
D2
→
J5
→
PC2(1-2)
→
R50
→
RL1
→
L2
→
L3
→
Ring
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KX-TDA6181X