General Information
The Piccolo modes were developed in the UK for
communications between Great Britain and its embassies and military stations all
over the world.
They are similar to the French Coquelet modes.
Usage:
§ Transfer of textual information (mostly encrypted) over HF.
Mode Details
|
|
Item |
Value |
|
Standard |
Modulation |
FSK |
|
|
Number of tones |
12 |
|
|
Shift (Hz) |
20 |
|
|
Bandwidth (Hz) |
300 |
|
|
Symbol rate (Bd) |
20 |
|
|
Alphabet |
ITA-5 |
|
Demodulator Settings |
Demodulator |
Multitone (MFSK) |
|
|
Tone duration (ms) |
50 |
|
|
TD tolerance (ms) |
2 |
|
|
No. of tones |
12 |
|
|
Tone position type |
Equidistant frequencies |
|
|
Tone distance (Hz) |
20 |
|
Features |
Demodulation |
yes |
|
|
Recognition |
yes |
|
|
Decoding |
yes |
|
|
Automatic Polarity Adjustment |
no |
|
|
Combination with other modems (modem list) |
yes |
|
Tuning |
The tuning frequency is the center of the signal | |
Table 171: Piccolo MK12
Figure 59: Piccolo MK12 Spectrogram