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4.14.3 - Demodulator Mode Selection

You can do this using AM, FM, SAM, USB, LSB, ( FSL, FSU, WFM), CWU and CWL, or you can use the  A,  F,  S,  U,  L,  C, and  W keys, respectively, except for the parenthesized modes.

4.14.4 - Demodulator Bandwidth Control

Each demodulator mode recalls its upper and lower bandwidth settings, which you can adjust by pressing ^ ↑, ^ ↓, ^ → and ^ ←, or by using the left or right mouse button when pointing at the demodulator edge on the spectrum display.

4.14.5 - Demodulator Carrier Offsets

For FSL, FSU, CWL and CWL, the desired signal is not properly tuned at its carrier frequency. Instead, you need to be tuned off-side; for instance, if you want a 1 KHz tone, in CW, then you need to be tuned 1 KHz above or below the CW signal, depending on which mode you are in.

You can set standard carrier offsets with Right-click FSL, Right-click FSH, Right-click CWL and Right-click CWU such that direct frequency entry using  RETURN lands you right on the correct frequency.

For instance, there are CW beacons on 14,100.000 MHz. Use Right-click CWU and set the offset to  1000 

While you're at it, set a center offset to avoid the I/Q spike many SDRs produce: Right-click CTR and set the center offset to  10000 

Now press  RETURN, type  14100c , and bingo, you're right where you need to be, 1 KHz offset from the CW signal, and about 10 KHz away from the SDR's center frequency.

Another example, WLO RTTY on 8,473.000 KHz:

Use Right-click FSL and set the offset to  1400 

Now press  RETURN, type  8473j , and again you're right where you need to be, 1.4 KHz offset from the RTTY signal, and about 10 KHz away from the SDR's center frequency.



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