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Transmission Modes WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V9.1.0
Hence adjustment of the center frequency must be accurate.
In contrast to PSK-31, this mode does not use DQPSK modulation.
PSK-AM
PSK-AM is a very narrow-band and reliable amateur mode developed by F6CTE. The aim of this experi-
mental slow mode is to allow chat communication between hams.
PSK-AM is similar to PSK-31, but uses its own fixed length 8 bit alphabet with a 5:3 ratio. Each character
is repeated 5 positions later. This diversity in time allows the correction of an invalid character.
Bitstream:
D(x): character
R(x): repeated character
PZVEI
The entire call number is transmitted by consecutive tones in decade sequence. When two identical digits
are to be transmitted consecutively, then an eleventh frequency is used as a repetition identifier.
If more than two identical digits are to be transmitted, the repetition tone is appended to the digit tone
(e.g., 22222 is transmitted as f2 fw f2 fw f2, where f2 is the tone for "2" and fw is the repetition tone).
In most systems the accuracy of the single frequencies has to be within +1/-1.5% of the nominal value.
For ZVEI modes having nominal tone durations of 70 ms, the duration of a single tone may vary ± 15 ms.
Decoding the selective calls is started by clicking on a system. If transmission and system selection con-
form, the call sign is displayed on the monitor. In the Options menu a Time stamp function can be ena-
bled to add date and time to each call.
Tone Allocation
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