AFSK Paging Link

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AFSKAudio Frequency-Shift Keying Paging Link
AFSKPaging Waterfallthmb.jpg
Frequencies 72 MHzMegaHertz (MHz) 10^6 Hz72,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
72,000 kHzKiloHertz (kHz) 10^3 Hz
,76 MHzMegaHertz (MHz) 10^6 Hz76,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
76,000 kHzKiloHertz (kHz) 10^3 Hz
,450 MHzMegaHertz (MHz) 10^6 Hz450,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
450,000 kHzKiloHertz (kHz) 10^3 Hz
,460 MHzMegaHertz (MHz) 10^6 Hz460,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
460,000 kHzKiloHertz (kHz) 10^3 Hz
,850 MHzMegaHertz (MHz) 10^6 Hz850,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
850,000 kHzKiloHertz (kHz) 10^3 Hz
,928 MHzMegaHertz (MHz) 10^6 Hz928,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
928,000 kHzKiloHertz (kHz) 10^3 Hz
72,000 kHzKiloHertz (kHz) 10^3 Hz
72 MHzMegaHertz (MHz) 10^6 Hz
928,000 kHzKiloHertz (kHz) 10^3 Hz
928 MHzMegaHertz (MHz) 10^6 Hz
Frequency Range 72 MHzMegaHertz (MHz) 10^6 Hz72,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
72,000 kHzKiloHertz (kHz) 10^3 Hz
- 928 MHzMegaHertz (MHz) 10^6 Hz928,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
928,000 kHzKiloHertz (kHz) 10^3 Hz
Mode NFMNarrowband Frequency Modulation
Modulation AFSKAudio Frequency-Shift Keying
ACFAutoCorrelation Function
Bandwidth 9 kHzKiloHertz (kHz) 10^3 Hz9,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
0.009 MHzMegaHertz (MHz) 10^6 Hz
kHzKiloHertz (kHz) 10^3 Hz
0.009 MHzMegaHertz (MHz) 10^6 Hz
kHzKiloHertz (kHz) 10^3 Hz
0.009 MHzMegaHertz (MHz) 10^6 Hz
Location Worldwide
Short Description It is easier to transmit the FSKFrequency-Shift Keying pager signal to the transmitter site as AFSKAudio Frequency-Shift Keying. It is changed to POCSAG format when re-transmitted.
I/Q Raw Recording
Audio Sample

It is easier to transmit the FSKFrequency-Shift Keying pager signal to the transmitter site as AFSKAudio Frequency-Shift Keying. It is changed to POCSAG format when re-transmitted.

These types of transmissions are used as uplinks at transmitter sites. In simpler terms, it is an FMFrequency Modulation modulated form of POCSAG that uses bell 202 AFSKAudio Frequency-Shift Keying tones, (being 1200 and 2200 hz mark and space AF's) following POCSAG format. Since POCSAG's actual waveform is just a pulse train, taking up 25 khz of bandwith, it is easier to modulate with these frequencies as to decrease bandwith on the uplink channel.


Samples[edit]





Decoding Software[edit]

PDW: But you will need to create a demodulation method and feed the incoming bits to PDW itself so that the demodulated POCSAG pulse train waveform can be read.

Additional Links[edit]

http://vocaroo.com/i/s1miV3hCCCfC

Additional Images[edit]

Mysterymodempic.png
Unknown 858p9 Longer.PNG
AFSK page link w DTMF.PNG