w <news:1mng9agao4yku$.137iwvtge9ikm.dlg@40tude.net>
dnia Tue, 30 Dec 2025 14:08:57 GMT user J.F pisze tak:

> Sygnał DCF chyba nie zawiera tygodnia.

hmm czat twierdzi ze ma


what information is transmitted in DCF77, Deutsche Funkturm 77.5 kHz
signal?


The DCF77 signal (Deutsche Funkturm 77.5 kHz) is a time signal
broadcast from Germany, and it transmits a variety of time-related
information to synchronize clocks and devices. Here's a breakdown of
the key information included in the DCF77 transmission:


### 1. **Time of Day (hh:mm:ss)**

* **Hours (hh)**: The current hour in a 24-hour format.
* **Minutes (mm)**: The current minute.
* **Seconds (ss)**: The current second (with a pulse to indicate each
second).


### 2. **Day of the Week**

The DCF77 signal includes a 3-bit field that indicates the current
**day of the week**, where:

* **0** = Monday
* **1** = Tuesday
* **2** = Wednesday
* **3** = Thursday
* **4** = Friday
* **5** = Saturday
* **6** = Sunday


### 3. **Day of the Year (Julian Date)**

The signal also includes a **day of the year** code, which specifies
which day it is in the year (from 1 to 365/366, depending on the year).
This is called the "Julian day."


### 4. **Week Number**

The DCF77 signal carries the **week number** (from 1 to 52 or 53) to
indicate which week of the year it is. This is encoded as a 6-bit
number.


### 5. **Year**

The signal includes information about the **year**, but it only
transmits the last two digits of the year. For example, for the year
2025, the signal would send "25."


### 6. **Leap Year Indicator**

A bit in the transmission indicates whether the current year is a
**leap year** or not. This helps in determining whether February has 28
or 29 days.


### 7. **Daylight Saving Time (DST) Information**

The signal contains an indicator for **Daylight Saving Time (DST)**. It
tells if the current time is in **Standard Time** (no DST) or **Summer
Time** (DST in effect).


* **DST (Daylight Saving Time)**: Typically the clocks are shifted by
one hour forward in the summer months.
* **Standard Time**: Regular time without the DST adjustment.


### 8. **Minute and Second Pulses**

* **Minute Pulse**: A pulse that marks the start of each new minute.
* **Second Pulse**: A pulse that marks the start of each new second.


### 9. **Data Format and Error Checking**

The transmitted data is encoded in a **biphase modulation** format.
Each second, the signal transmits a series of bits, and devices can
decode these to extract the time information. Error-checking is
included to ensure that the data received is correct, and the
transmission also uses a **parity bit** for synchronization and
integrity checks.


### 10. **Signal Format**

The signal is transmitted at a frequency of **77.5 kHz** and has a
relatively low bit rate, meaning that each second of transmission
encodes just a small amount of data. However, over time, these bits
accumulate, allowing a receiver to correctly synchronize to the time
and other parameters.

---

### Summary of the Main Data Sent:

* **Current time**: hour, minute, second.
* **Day of the week**.
* **Julian day** (day of the year).
* **Week number**.
* **Year** (last two digits).
* **Leap year indicator**.
* **DST (Daylight Saving Time) status**.

This time signal is used to synchronize clocks in homes, offices, and
various devices across Europe and beyond, and it is especially useful
in situations where accurate timekeeping is important.


--
Czesi maja Skode Rumuni maja Dacie
a Polacy maja Fiata Polio Weekend