Panasonic Va-208 Key Telephone System Installation Manual

							7. TONE Circuit 
7.1 450Hz oscillator circuit: 
Used for Intercom call tone. 
7.2 550Hz oscillator circuit: 
Used for Intercom dial tone, Busy tone and Ring back tone. 
7.3 16Hz oscillator circuit: 
Used for CO incoming call tone which modulated with 450Hz/550Hz by 16Hz. 
-8-  
						

							8. Link IC Circuit 
Intercom Speech path 
Intercom Incoming Call Tone.RT 
.: 
COL 1 Speech Path 
COL 2 Speech Path 
Door Intercom Speech Pat 
+3v t RAI 
, 
ITT 
B 
To Extension Card 
(Used for TEL 5 to 8) 0 
: 
-il 
4c 
5 
6 
7 
Release and connection of TEL and IC (IC9 to ICI I). 
Release and connection between TEL and link IC is executed by control data from lC6. 
The control data output from IC6 is output to STR, DO, A to E pin terminal of 1%. 
The operation of the data input to IC9-ICI 1 (STR, DO, A-E terminal) is as follow: 
l STR is the data for the activation of IC. 
l DO is the data to make a selection either connection or release of TEL. 
0 
A to E is the data for selection of cross points. 
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							Link IC (MN6105) operation 
Cross point I 
To Extension Card 
(Used for TE L5 to 8) 
NOTES: . 
When the status of 
and DO (pin No.4) 
of A to E and ratch 
When the status of Link IC input terminal SRT (pin No. 10) 
is @ 
, Link IC read out the address data 
the cross point. NC = Keep the present operation. 
ON = Ratch 
Link IC input terminal SRT (pin No. IO) OFF = Release the ratch. 
is @ and DO (pin 1No.4) is 0, Link IC read the address 
data of A to E and release the ratch of cross point. 
In case of Link IC input terminal SRT (pin No. IO) is 0, 
the Link IC keep present operation even the data input to 
DO address (Shall not operates ratch or release). 
Data input timing chart of Link IC ON and OFF 
operat!on.(Example of cross point IS 0) 
Can read I”. 
The relation chart 
for input and connections 
I Cross I inout Condltlon I I 
The Link IC Input data chart for intercom incoming call tone 
emission at TEL 1. (Used IClO and cross point is 0) 
Intercom incoming call tone(400Hz, 
1 sec./and 2 sec. 
IOFF 
Output 
state ON ON 
OFF 
OFF ON 
2SEC 2SEC 
1SEC 
1 SEC 
1SEC 
_. 
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							9. Data 
Communication between TEL and KSU (1) 
Circuit 
3 
( H 
L 
rlloo 
T --_  TEL 
No. 1 
* 12v 
RI03 
+ Cl02 
9.1 
(11 
(2) 
9.2 
Dato 
Communication 
6J.J 
I HBl (HB2006) Circuit 
+ c4 
RI7 RI9 LT 
05 -14 
RI6 
015 
016 
D3 R21 
R22 R20 
I + c5 
R23 
R25 
07 -17 
R24 
016 
019 
D4 
R26 R27 
R26 
Supply of the control current to H, L terminal. 
(For data communication and power supply 
source to the TEL). 
+lZV is supplied to H,L terminal via CHIOI choke coil, and supplied DC voltage is superpaused to communica- 
tion data between TEL and KSU. 
Output the data from KSU to TEL. 
The data from HBI (pin No. 10) is output to pin No. 3, and output is to H, L terminal via TIOI (pin No. 9, 10 to 
No. 7, 6). 
Data input from TEL to KSU. 
The input data from TEL is induced to TIOI (pin No.7, 6 to No.4, 2) via CIOI, and input it to HBI STAT (pin 
No.~), then output it from HBI (pin No. 11). 
DC power supply to the speech path.(To the T,R terminal) 
DC power supply to the speech path is supplied to TEL speech circuit. The supply process for +12V is for 
positive side via R 103, QIOI and for negative side via 0102, R 104. 
The function of R103, 0101, Q102 and RI04 operates as coil, and the voice signal and other tone signals is 
induced to T102 and supply to the speech path.  
						

							10. Data Communication between TEL and KSU (2) 
T301 
T401 
ICl (RST) IC4 
t 
Interrupt data input 
Control from TEL 
Data output to TEL 
Inhl (TEL1 ~4) 
Inh2 (TEL5-8) 
Data input from TEL 
I 4 
3 3 IC6 
10.1 The circuit for read in the data from TEL to KSU. 
The data sent from TEL is input to HBI (pin No.4) and output it from HBI (pin No. 11). The output data is in- 
put to ICY (pin No. 13) via D15 (Low active). The input data of IC21 (pin No. 13) is input to IC21 (pin No.9) 
through pin No. 11 when @ status on pin No. 12. 
The input data of IC21 (pin No. 9) is output to IC5 (pin No.4) from pin No. 10 when @) status on pin No.8, 
then the data is read into KSU from TEL. 
10.2 Data output from KSU to TEL (IC4 pin No. 13). 
The data from KSU is output @ (Low active) from IC4 ( pin No. 13), and input it to IC21 (pin No. 5, 6). 
When the input data of IC21 (pin No. 5, 6) is @ status, the data @ is output from pin NO. 4 to IC21 (pin 
No. 1). 
When @ status on IC21 (pin No. 2), the input data of IC21 (pin No. 1) is output the data 0 status from IC21 
(pin No.3) to HBI (pin No. lo), then output the data from HBl (pin No.3) toTEL. 
10.3 Data communication access input (Inh) of HBI. 
The signal for Inh 
- 5v is output from IC4 (pin No. 12) to HBl (pin NO. 12). 
I65.2m Sec. 
When the Inh signal is @ status, HBI communicates with TEL and the communication is executed sequentialy 
from TEL 1 to TEL 4 for every 65.2 msec. 
10.4 HBI (A, B) address input. 
The address input is output to HBl (pin No.8, 9) from IC6 (pin No.4, 3). and the output is connected sequen- 
tialy from TEL 1 to TEL 4 and TEL 5 to TEL 8 for every 65.2 msec. 
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							11. IC Port Explanation 
11.1 IC4 (UPD8255AC) 
COL 2, Incoming call COL 2, Incoming call detection 
COL 2 seize 
COL 2, ON status on dialing(DP/DTMF) 
COL 1, Hold tone sending 
atus on disable 
ata output from KSU to TEL/@ -1, 0 
-0 
late : All letters for I/O is “in” or “out”. H 
: enable L : disable 
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							11.2 IC5 (UPD8255AC) 
SLT dialing output. (eg. No.7 dialing 
0 status on port A4, 5, 6) 
on Power ON 
13 
12 
11 
10 4 
DPH Busy 
@status on Normal/O status on Busy 
5 DPH Sel 
@status on B selection/@ status on A selection 
6 EPA lontal 
@status on Normal/@ status on EPA 
1 SPC (TEL 3 to 8 on power faiIure)@status on 
power failure/@ status on Normal 
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							11.3 IC6 (UPD8255AC) 
(@ status on CO line seizure/@ status on  
						

							W EXPLANATION OF CIRCUIT OPERATION (KEY TELEPHONE) 
1. Conversation 
Hand set (Transmitter and Receiver) is connected to T, R line when HSI is [ON] (OFF-HOOK). 
T 
I, 
HSl 
+ 
+ 
MIC 
- 
Incoming Signal 
R36 
, 
R24 
R21 R22 
08 izC15 
: R33 
1.1 Receiving 
The voice signal input is emitted from receiver via the sequence of: 
T, R terminal + HSl 
[ONI -+ DBI (Rectifier) + Sink circuit (Provided to maintain conversation quality by 
constant current 
supply for various distance condition to the Central Office Exchange) + Tl + Q4 (Receiver 
amp.) + R (Receiver). 
1.2 Transmitting 
Transmission of the voice signal is output to T, R terminal via following sequence: 
MfC + Q6 (Transmitter amp.) + Tl -+ DBI + HSI [ON] + T, R terminal. 
NOTE: When the transmission voice level is over from specified level, 07 to Q9 (The receiver mute circuit) is 
suppress the side tone by 09 [ON,] 
. 
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							2. Functional Operation Circuit 
HS3 b 
I $R26 
/ 
1 f SPKRL PF3 
P70 
P71 
P72 
P73 
1 
2.1 
CO lamp flickering during CO line talk (eg. COL 1). 
When CO incoming call lamp data is arrived to TEL from KSU, ICI pin No.32 is output the control data (0.5 
sec. @ , 0.125 sec. @@@ and 1.5 set 0). The lamp control data turn on the COL lamp when the status is 
@and turn off the COL lamp when the status is @ 
. This is the reason for COL lamp is flickering. 
2.2 
Sounding of CO incoming call tone. 
When the CO incoming call tone sounding data is input to TEL from KSU, ICI pin No. 37 is output the @ 
status. Then @ status is input to IC5 pin No. 5 via D5, and turn IC5 [ON]. From the above process, the CO 
incoming call tone which sent from T, R terminal is sent out from IC5 pin No. 3 to pin No. 4. CO incoming call 
tone which sent out is input to IC6 via C15, and the input data amplified by IC6 then emit the call tone from 
SP. 
2.3 
Intercom call tone sounds and Intercom voice call. 
cr. Cl3 
T2 
P60 
P61 
P62 
PF7 
P90 
P91 
P92 
K4 = 
VRl 
R41 
4 
P20 
P63 
P62 
PBI 
1 P60) 
When the Intercom call sounding data and voice call data is sent to TEL from KSU, output the @ status to 
ICI pin No. 36. @) status output is sent to IC5 pin No. 5 via D4 and turn on IC5 to ON. Following operation as 
same as clause 2.2. 
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