GPS to DCF77 Module
http://www.grother.de/gps-to-dcf77-module.html

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GPS – RTC to DCF77 Module for Clock with DCF in.

 

Variant 1 with cable connection.

 

Assembly instructions, here

 

- GPC Module received UTC  (Coordinated Universal Time ) Time, Date and Weekday     

- 5 Dip Switches adjusting local Time ( SW 5 is for + or – time selection )

- Solder bridge for 12h format selection.

- Switch to select start and end of summertime.

 

The MCU unit get the UTC time and modified Time and Date for the local area.

Local time and date are programmed each minute by the RTC 3231 module, which

has a battery to support its internal memory.

 

 

The RTC output controls the MCU unit, which converts the signal to real DCF

Protocol. Positive or negative output is possible.

 

First Usage

 

- Set all DIP switches to OFF position including in the SW Summertime

- Install the CR1220 battery

- Connect the +/- 5 Volt supplies from your clock, external USB Power supply or Power Bank

 -Solder the Sig. point to your clock.

  Note: most clocks have – signal input, + signal is possible when R3 is soldered to * position.

 

The best location for the GPS receiver is on the window ledge.

In my office in the Ground floor it works too.

The GPS module has a dedicated rechargeable battery, allowing the time and date

Data to be stored in the internal RTC circuit when the GPS signal is out of range.

Please allow 30 to 60 minutes for battery charging and time to acquire the GPS signal.

 

The red LED from the GPS module is on and the blue DCF LED on the main board flashes.

When the GPS signal from 3 satellite is received the red LED flashes.

The blue GPS LED is on for 2 seconds each minute. ( i.e.-on at second 00 to 02 ), which

means  the time and date has been written to RTC 3231 module.

 

After 2 – 3 minutes your clock will display UTC time.

 

Adjusting Time for your local area.

 

Look at the world map and search for the United Kingdom. There is UTC time.

If you look to the west site, it is UTC+ time. Look for the east it is UPS – time

Check your local time to see what time is it and compare with the following table.

 

DIP SW settings:

 

Time

SW 1

SW 2

SW 3

SW 4

SW 5

Time

SW 1

SW 2

SW 3

SW 4

SW 5

UTC

 

 

 

 

 

UTC

 

 

 

 

 

UTC + 1h

on

 

 

 

on

UTC - 1h

on

 

 

 

 

UTC + 2h

 

on

 

 

on

UTC - 2h

 

on

 

 

 

UTC + 3h

on

on

 

 

on

UTC - 3h

on

on

 

 

 

UTC + 4h

 

 

on

 

on

UTC - 4h

 

 

on

 

 

UTC + 5h

on

 

on

 

on

UTC - 5h

on

 

on

 

 

UTC + 6h

 

on

on

 

on

UTC - 6h

 

on

on

 

 

UTC + 7h

on

on

on

 

on

UTC - 7h

on

on

on

 

 

UTC + 8h

 

 

 

on

on

UTC - 8h

 

 

 

on

 

UTC + 9h

on

 

 

on

on

UTC - 9h

on

 

 

on

 

UTC + 10h

 

on

 

on

on

UTC - 10h

 

on

 

on

 

UTC + 11h

on

on

 

on

on

UTC - 11h

on

on

 

on

 

UTC + 12h

 

 

on

on

on

UTC - 12h

 

 

on

on

 

 

Set the switches accordingly and after 2 – 3 minutes the time, date and weekday is displayed on your clock.

 

Notes.

 

The GPS reception can be restricted by bad weather, cloudy or fog so is it not necessary to receive GPS continuously, because the internal RTC unit from the GPS module will keep good track of the time.

 

There is also a precise RTC 3231 module on main PCB that controls the clock.

 

 

Enclosure: 90mm x 57mm x 24mm, ABS, black

 

 

 

If you order the GPS DCF77 Kit with IV-11 DCF melody clock you get a 3.5mm audio cable

for connection. The IV-11 Kit with wireless Temperature included a USB cable.

 

 

Variant 2 with wireless Bluetooth connection.

 

This version has a separate small case for GPS module and Bluetooth transmitter.

 

On the main PCB with MCU, RTC 3231 and DIP SW is a Bluetooth Receiver. The Bluetooth connection is always online.

 

                   

 

Top site with GPS module                                                                 Bottom site with BT Transmitter module

 

 

The  5 Volt USB Power adapter is included in this KIT.

 

Enclosure for GPS – BT Transmitter: 65mm x 46mm x 25mm, ABS