Wavecom W40PC, Руководство пользователя

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General Operating Procedure WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
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The
AF-IN
has a range of 0 – 16 kHz. This input should be used
when the source is an AF output (line or speaker) or a 12.0 or 12.5
kHz IF output used in professional digital recorders.
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The IF-IN-VAR has a range of 14 kHz – 1.5 MHz. Most receiver
IFs are within this range.
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The IF-IN-10.7 input has a range of 10.685 – 10.715 MHz (or
21.385 – 21.415 MHz). This IF is common for VHF-UHF
receivers.
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The
IF-IN-21.4 input
has a range of 21.385 – 21.415 MHz. This
IF is common for VHF-UHF receivers.
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The
DIS input
(Discriminator) on the W40PC has a range of 0 –
20 kHz. This input is supported by a few VHF-UHF receivers and
facilitates the reception of ”Direct FSK” signals like POCSAG or
PACKET-9600. The advantage of this input is the easy handling.
Only the gain has to be adjusted. There is no need for an
adjustment of the center or the translation. DIS is only released for
”
Direct FSK ” modes.
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On some decoders IF-IN-VAR is labeled as HF-IN.
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The EXT-DEM-IN input (W41PC-MKII and W51PC) must be
used if an external demodulator is to be connected. The minimum
input level is TTL level (LO = 0 V, HI = +5 V) and the maximum
is RS-232C level (LO = -12 V, HI = +12 V). Note that utilizing this
facility will disable certain decoder functions. Thus this input
should be employed for special purposes only.
Translation
Adjusting the translation frequency and the center frequency will adapt the DECODER input
to a receiver IF output.
The minimum translation frequency resolution available with the DECODER is 1 Hz. The
effective center frequency is the sum of the translation frequency and the center frequency. The
function is similar to the mixing of the signal frequency and BFO of a receiver.
An exception is the
FFSK
demodulator for direct frequency modulation. In this case the
indicated translation frequency is equal to the effective center frequency.
An example for an HF receiver and ARQ-E mode:
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Receiver IF 455'000 Hz
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"Translation" 453'300 Hz
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"Center" 1700 Hz
The advantage of this method is that the user only needs to know the center frequency.
Another example for an VHF-UHF receiver and POCSAG mode:
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Receiver IF 455'000 Hz
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"Translation" 455'000 Hz
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"Center" 0 Hz
In this case the translation frequency is equal to the center frequency.
Gain
The input gain adjustment range is 0 - 100 % corresponding to an input sensitivity of the