General Information
FLEX is a high speed pager protocol developed by Motorola. Two Messaging Systems are currently defined, the FLEX one-way data messaging protocol and the ReFLEX two-way data messaging protocol.
Usage:
§ Broadcast paging over VHF.
Mode Details
|
|
Item |
Value |
|
Standard |
Modulation |
FFSK-2 / FFSK-4 |
|
|
Symbol rate (Bd) |
1600 / 3200 |
|
|
Data rate (bps) |
1600 / 3200 / 6400 |
|
|
Coding |
BCH(31,21) |
|
|
Alphabet |
ITA-5 |
|
Demodulator Settings |
Demodulator |
FSK 2 matched |
|
|
Symbol rate (Bd) |
1600 |
|
|
SR tolerance (Bd) |
5 |
|
|
Shift (Hz) |
9600 |
|
|
Shift tolerance (Hz) |
10 |
|
|
Modem type |
Synchronous |
|
Features |
Demodulation |
yes |
|
|
Recognition |
yes |
|
|
Decoding, FFSK-2 / FFSK-4 |
yes / no |
|
|
Automatic Polarity Adjustment |
no |
|
|
Combination with other modems (modem list) |
yes |
|
Tuning |
The tuning frequency is the lowest tone. | |
Table 12: FLEX
Figure 10: FLEX Spectrogram