kopia lustrzana https://github.com/jamescoxon/dl-fldigi
60 wiersze
1.9 KiB
Plaintext
60 wiersze
1.9 KiB
Plaintext
/**
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\page wwv_tx_mode WWV transmit mode
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\tableofcontents
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The WWV mode is normally used to measure the offset of the sound card
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oscillator. (see \ref digiscope_display_wwv_mode "WWV ppm measurement").
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<br>
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It can also be used to transmit time tick signals similar to the format
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that is used by WWV. The WWV modem sends a time tick which is a
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200 msec wide pulse at a once per second rate when the T/R button is
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enabled. This pulse is shaped with a 4 msec raised cosine shape
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on the leading and trailing edges to reduce key clicks. The
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accuracy of the transmitted time tick is solely dependent on the
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accuracy with which the WWV ppm measurement was performed.
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<br>
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The purpose of the WWV time tick transmission is to allow other
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stations to calibrate their sound cards against your calibrated
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system. This can be used to align all systems in a VHF/UHF net
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for example. It is only necessary for one of the net members to
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be able to calibrate his or her sound card against WWV. The
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other's would then be calibrated by proxy use of the WWV time tick
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transmit mode. This can even be used in the case where no member has
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access to a HF transceiver. The "master" station would set the Rx
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and Tx ppm settings to zero. It would then transmit the time tick
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signal for the other stations to calibrate their sound cards against
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the master sound card. Having all of the stations calibrated in
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this way will insure that the modem decoders will give maximum
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performance. Here is an example of an \ref inline_macro_page "advanced macro"
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that will send a CW announcement, 2 minutes of time ticks and end with
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another CW announcement.
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<br>
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\verbatim
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<MODEM:CW>
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<!GOFREQ:1000>
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<!WPM:24>
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QRZ QRZ de <MYCALL> <MYCALL>
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2 minute time tick cal run follows
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<IDLE:2>
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<!MODEM:WWV><!IDLE:120>
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<!MODEM:CW><!IDLE:2>
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end of time tick run
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de <MYCALL> k
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<TX><RX>
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\endverbatim
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<br>
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<br>
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\ref wwv_tx_mode "Return to Top of Page"
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<br>
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\ref main_page "Return to Main Page"
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*/
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