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Parts explanation of RCC with LSD

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 kit is designed so that a receiver circuit and a display control circuit can be installed in a different place. 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 ( S813-50HG ) This is a regulator for making the power supply (+5V) of a receiver circuit. Data sheet for S813-50HG
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.	Case As the case of receiver PR-140G made by TAKACHI is used. It's the case with a width of 140mm, a height of 45mm, and a depth of 90mm.
RJ-45 connector RJ-45 connector is used for the cable connector of a receiver and a display processor.	Stud This metal stud is used to fix a printed circuit board on the case.
PIC16F877 In the kit of TriState, PIC16F873 is used and the port to control a display unit outside isn't enough. So, in this circuit, 877 with many ports is used by 873 higher rank models. Description of PIC16F877 Data sheet of PIC16F877
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.	LEDs These LEDs are used in order to check the operating state of a circuit.
Liquid-crystal-display panel ( SC1602BSLB ) This is a liquid-crystal-display panel (LCD) for displaying time. This is a liquid crystal display made by SUNLIKE Co. in Taiwan. The display of two lines can be performed by 16 characters per line.
Button switch This clock has a function to control the outside circuit when becoming a set time. These switches are used in order to set up the time.	Variable resistor This is a variable resistor for adjusting the display contrast of LCD.
Melody IC ( SVM7975C ) This is melody IC. 8 pieces of music are memorized in this IC. Title Green-Sleeves Valse Favorite Fur Elise Holderia Heavenly Creatures Amaryllis Ich bin ein musikante Home On The Range Pin arrangement 1 TST For test 10 ENV2 Envelope 2 OSC1 OSC control 11 ENV1 Envelope 3 OSC2 OSC control 12 MO Output 4 MS1 Mode select 13 PI AMP input 5 MS2 Mode select 14 OUT1 AMP output 1 6 MS3 Mode select 15 OUT2 AMP output 2 7 MT Mode select 16 STP Stop 8 B/E Mode control 17 CHK For test 9 Vss GND 18 Vdd Power Rating Item min typ max Unit Power supply 1.2 1.5 3.4 V Consumption current - 100 200 uA
Low-frequency amplifier ( LM386N-1 ) This is the small amplifier which is possible to let out an about 500-mW output power. It is convenient because it doesn't need a related part. This is used for the amplification of the time signal( Electronic music ). Datasheet for LM386
Volume This is the variable resistor to adjust the volume of the time signal.	Knob This is the knob which is used for the volume.
Speaker This is the small speaker to sound the music of the time signal.	Electrolytic Capacitor This is the capacitor used for coupling of a time signal circuit.
Resistor This is the small resistor of 1/6W.	Multilayer Ceramic Capacitor These capacitors are used as a high frequency bypass of a power supply system.
PIC16F628 In order to make all the 7 segments LED turn on simultaneously, a big power supply is required. With this equipment, the lighting position of LED is changed at high speed, and the power of it is saved. The number of the 7 segments LED to control is 14. In order to control such LEDs, PIC16F628 is used. The dot matrix LED of 8x8 is used for the display of a day of the week. In order to control this LED, another PIC16F628 is used. Description of PIC16F628 Data sheet of PIC16F628
3-to-8 line Decoder ( 74HC138 ) In order to control the display position of a dot matrix LED, the 8-bit decoder is used. Only one of 8 bits is set to L level with a 3-bit control signal. Data sheet of 74HC138	CPLD for latch register ( XC9572-PC84 ) CPLD is used in order to hold the display state of the 7 segment LED. A circuit becomes compact by CPLD. Data sheet of XC9572
NPN transistor ( 2SC1815 ) This transistor is used for the display unit. Data sheet of 2SC1815	PNP transistor ( 2SA1015 ) This transistor is used for the display unit. Data sheet of 2SA1015
7 segment LED for Hour and Minute 120mm(H), 90mm(W), 15mm(D)	7 segment LED for Second 50mm(H), 37mm(W), 13mm(D)
7 segment LED for Year, Month, and Day 33mm(H), 22mm(W), 9mm(D)	Dot matrix LED for Week 33mm(H), 33mm(W), 4mm(D)
LED for display pause Square LED is used for the pause of Hour and Minute. Long and slender LED is used for the pause of Year, Month and Day.	IC socket It sometimes removes PIC and CPLD to rewrite a program so an IC socket is used.
3 terminal regulator ( 7805 ) This is a regulator for making the power supply (+5V) of a CPU unit. The regulator for 100mA was used at the beginning.However, because about 100mA current flowed at the time of battery drive, it was changed into 1A type for safety. Data sheet for 7805	3 terminal regulator ( 78L05 ) This is a regulator for making the power supply (+9V) of LM386. Data sheet for 78L09
Switching power Input : AC100V Output : 12V-1A, 5V-2A	Diode This diode is used in order not to pass current except a receiving unit and a CPU unit at the time of the battery use for backup.
Battery The rechargeable battery of 2500mAH is connected to 6 series.	Battery case I used a plastic case.
Power cable A vinyl cable with the AC plug is used.	AC cord protector It is used in order to prevent contact of a power cable and a case.
Printed board Universal printed board with 55 x 40 halls is used. As the board which LEDs are mounted, cheap paper epoxy board is used. The glass epoxy board is used for the circuit.	Metal fittings for Display panel A large-sized LED is mounted on more than one printed board. The L angle which is made of aluminum is used to connect those printed boards.
Stud A circuit board is installed in the back of the LED board. In order to make the space of wiring, the 10mm stud is used.	Case YM-400 which is made by the TAKACHI Inc. is used. 400mm(W), 250mm(H), 55mm(D)
Strap This strap is used to prevent the fall of the battery.	Chain This chain is used to hang a clock on the wall.