Table of Contents
206.204.62 KORTLINJE
Disassembly
Main Components
206.204.62 KORTLINJE
Alarm clock with hygro-/thermometer, red, 18x6x7 cm
Disassembly
Battery cover
Loosen 2× M2×7 captive screws
Remove the part
Battery holder and rear button plate
Remove 5× ST1.7×6 screws
Lift up the part
Insert a long screwdriver e.g. a test pen to push on one of the retaining tabs on the rear plate
Pull upwards on the corner to free it (do not pull too hard to avoid breaking the other tab that is still engaged)
Push on the remaining retaining tab while pulling upwards to free it too (be careful not to re-latch the other tab)
Remove the part
Power board
Remove 4× ST1.7×6 screws
Lift up the part and flip it over to the bottom side of the board to free it
The part cannot be removed fully as the wires are soldered on both ends
Mid-frame
De-route the power cord from the cord grip
Remove 6× ST1.7×6 screws
Remove the part
Main board
Remove 8× ST1.7×6 screws
Lift up the part and free it
The part cannot be removed fully as various wires are soldered on both ends
Main Components
U6 is an unmarked IC (SOIC-16N package) and likely an 8-bit MCU running the show
Pin 3 ↔ VPP testpoint
Pin 4 ↔ CLK testpoint
Pin 7 ↔ GND
Pin 11 ↔ SDA
Pin 12 ↔ SCK
Pin 14 ↔ Buzzer
U1, U2, U4 are VINKA VK1640 (SOP28 package) LED drivers
U3 is an unmarked IC (TSSOP-24) and likely an RTC
Pin 2 ↔ GND
Pin 14 ↔ CK testpoint
Pin 15 ↔ 32.768 kHz crystal
Pin 16 ↔ 32.768 kHz crystal
Pin 23 ↔ V
Photodiode for automatic brightness
Sensors in the clock leg with a vent
Analog humidity sensor
Analog thermistor
Buzzer on this external sensor PCB