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Parts explanation of RCC with MSD

Receiver unit		CPU unit		Display control unit
Display drive unit		Display panel		Case

Receiver unit	to TOP
Bar antenna This is the bar antenna to receive the radio wave of 40KHz. Time-Code Receiver IC ( U4226B ) This is the exclusive use IC to take out the time information which is carried in the radio wave of 40KHz. At the data sheet, a radio clock system in some countries is introduced. Data sheet for U4226B Crystal oscillator for 40kHz These crystal oscillators are used to receive the radio wave of 40KHz, being connected with receiver IC(U4226B). High precision film capacitor In order to carry out operational stability of the receiver circuit, the capacitor of high capacity accuracy is required. Ceramic capacitor This is also used for a receiver circuit. Photo-coupler ( TLP521-1 ) The receiver unit and CPU unit are installed and they are connected by a cable. Therefore, the photo coupler is used for the signal drive. Data sheet for TLP521 NPN transistor ( 2SC1213 ) This transistor is used for the LED drive, etc. Data sheet for 2SC1213 Choke coil This is a coil for removing the noise generated when a receiver unit and a CPU unit are connected by a long cable. Electrolytic Capacitor These capacitors are used in order to stabilize the supply voltage of a circuit. 3 terminal regulator ( 78L05 ) This is a regulator for making the power supply (+5V) of a receiver circuit. Data sheet for 78L05 Printed circuit board The printed board of the receiver unit is using the one of the kit. IC for the receiver, chip resistors and chip capacitors are already mounted on the board. LED for TCO This LED indicates the TCO(Time Code Output) signal. This LED is attached in a case. RJ-45 connector RJ-45 connector is used for the cable connector of a receiver unit and a CPU unit. Stud This metal stud is used to fix a printed circuit board on the case. Case As the case of receiver PR-140B made by TAKACHI is used. It's the case with a width of 140mm, a height of 45mm, and a depth of 90mm.
CPU unit	to TOP
PIC16F873 PIC16F873 is used for the clock. This IC is processing the check of the received signal which the receiver detected, conversion of time information, and the display to LCD. Moreover, the function to read time with a personal computer using a RS232C interface is carried. This RS232C interface function is used this time. Data sheet for PIC16F873 High precision oscillator ( TCXO ) This is a high precision crystal oscillator for displaying exact time, even when a radio wave stops. Oscillation frequency is 12.8MHz. NPN transistor ( 2SC1815 ) This transistor is used for the LED drive, the external circuit drive, etc. Data sheet for 2SC1815 3 terminal regulator ( 7805 ) This is a regulator for making the power supply (+5V) Data sheet for 7805 Diode bridge This is a 1A type diode bridge. This diode is used in order to prevent the polar error at the time of power supply connection. Since power supply connection is not changed with this equipment, this part is not used. IC socket This is an IC socket for PIC16F873. Since 873 is the slim type of 28 pins, it can be used combining two sockets for 14 pins. LED LED is attached to the kit. However, it has high brightness because of a clear type, and light is dazzling. Therefore, it was exchanged for LED of a soft light. Variable resistor This is a variable resistor for adjusting the display contrast of LCD. Since the parts attached to the kit broke, I used the part of a different type. Button switch This switch is used for a setup of the clock function. Liquid-crystal-display panel ( SC1602BS-B ) This is a liquid-crystal-display panel (LCD) for displaying time. The display of two lines can be performed by 16 characters per line. LCD mounting supporter Although one side of LCD is fixed by a connector, other one side is not fixed. This is a part used for the side which is not being fixed. Electrolytic Capacitor This capacitor is used in order to stabilize the supply voltage of the circuit. Insulated washer The circuit pattern is running near the attachment section of LCD. The insulated washer is used in order to prevent a short circuit with a nut. Printed circuit board This is the printed circuit board of a CPU unit. The RS232C driver IC, the chip resistors etc. are already mounted. Stud This is the parts for fixing the printed circuit board to a case. The length is 10mm.
Display control unit	to TOP
PIC16F877A In a display control unit, the function to receive time information from a CPU unit by asynchronous communication, and the lighting control function of LED are performed. Asynchronous communication is realized by the USART function of PIC. Transmission speed is set as 9600bps. In order to carry out LED lighting control of 12 figures from a year to a second, 877 with much I/O port is used. PIC16F977A is used in fact. Although a function is the same as 877, the specification of program writing is different. Therefore, it is necessary to use the programmer corresponding to 877A. Data sheet for PIC16F877A PIC16F628 The dot matrix LED of 8x8 is used for the display of a day of the week. In order to control this LED, PIC16F628 is used. Data sheet for PIC16F628 3-to-8 line Decoder ( 74HC138 ) This decoder is used in order to control the display sequence of the dot matrix LED for week display. Data sheet for 74HC138 RS-232 Drivers/Receivers (ADM232AAN) This is IC for a RS232C interface used for communication with a CPU unit. Data sheet for ADM232A PNP transistor ( 2SA1015 ) This transistor is used for the drive of a dot matrix LED of the week. Data sheet for 2SA1015 IC socket Since PIC rewrites a program, an IC socket is required for it. Other ICs are O.K. without a socket. Printed circuit board 24 x 30 holes board is used. Ceramic resonator This is a 4MHz clock oscillator for PIC16F877A. Since PIC16F628 used the built-in clock oscillator, the resonator does not use. Resistor This is the resistor of 1/6W. Multilayer ceramic capacitor This is used in order to make line voltage (about +/-10 V) with the driver/receiver of RS-232C. Button switch This is the small switch used in order to perform the lighting check of all LED. Stud This is the parts for fixing the printed circuit board to a case. The length is 10mm.
Display drive unit	to TOP
3-to-8 line Decoder ( 74HC138 ) This decoder is used in order to control the lighting position of each LED. Data sheet for 74HC138 Sink Driver ( TD62003 ) Seven NPN transistor circuits by which Darlington connection was made are built in this IC. This is used for segment lighting control of LED. Data sheet for TD62003 PNP transistor ( 2SA1015 ) This transistor is used for LED drive. Data sheet for 2SA1015 NPN transistor ( 2SC1815 ) This transistor is used for LED drive. Data sheet for 2SC1815 3 terminal regulator ( 7805 ) This is a regulator for making the power supply (+5V) Data sheet for 7805 IC socket In this circuit, the socket is used for all ICs. Resistor This is the resistor of 1/6W. Heat sink In order to radiate the heat of 3 terminal regulator, the 2mm aluminium board is used. Electrolytic Capacitor This is the capacitor which reduces the ripple of a power supply. It is 100uF/16V type. Multilayer ceramic capacitor This is a capacitor for noise removal of a power supply. Printed circuit board 38 x 62 holes board is used. Stud This is the parts for fixing the printed circuit board to the display panel. The length is 5mm.
Display panel	to TOP
LED for Hour and Minute 50mm(H), 37mm(W), 13mm(D) LED for Second 33mm(H), 22mm(W), 9mm(D) LED for Year, Month and Day 18.8mm(H), 12mm(W), 8mm(D) LED for Week 16mm(H), 16mm(W), 4mm(D) LED for Colon This is LED used between Hour and Minute display. LED for Hyphen This is LED used between Year and Month, and Month and Day display. Resistor 1/6W are used except R62. 1/2W are used for R62. Printed circuit board 38 x 62 holes board is used. Metal fittings for Display panel The display panel consists of the printed circuit boards of two or more sheets. The angle is used for those connection and reinforcement. Display mask Three kinds of material is used. A transparent acrylics board with 0.5mm thickness at the bottom. Black paper for mask at middle. The purple acrylics board of 2mm thickness at the top. Stud In order to fix a display panel to a case, the 15mm stud is used. The 10mm stud is used for fixation of a display mask. Since the height of LED is 13mm, the washer is used for height adjustment.
Case	to TOP
Case The part case made from HOZAN (B-10-AA) is used for the case. The inner size of the case is 245mm(W), 176mm(H), and 34.5mm(D). RJ-45 connector This is a connector linked to a receiving unit. Power supply connector This is the connector which connects a power supply adapter. AC adapter This is the adapter which changes 100VAC into 12VDC. Current capacity is 200mA. The consumed electric current of this clock is 100mA or less. LAN cable The LAN cable is used as a cable which connects a receiving unit and a CPU unit. Chain The chain was used in order to hang a clock in a wall.