Now listen to the transmitted audio patterns used by the ARQ modes.
Observe the sending stations data pulse followed immediately by the receiving stations shorter acknowledgement pulse. Note: does not apply to Clover, which is a semi-duplex mode simulating full duplex operation.

PACTOR Windows Wave file 8 bit recording (79K), 11K sample rate (6.7 seconds)
CLOVER Windows Wave file 16 bit recording (74K), 22K sample rate (6.75 seconds), MS ADPCM compression.
G-TOR Windows Wave file 8 bit recording (76K), 8K sample rate (9.7 seconds).
AMTOR Windows Wave file 8 bit recording (54K), 8K sample rate (6.7 seconds).
PACTOR II Windows Wave file 8 bit recording (54K), 11K sample rate (4.96 seconds), no compression.

    Non ARQ modes:   FELD HELL

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