SAMPLING


The SAMPLING rate defines the available bandwidth (frequency coverage) in wideband files.

JAGUAR is designed for MW DXing and thus it supports only two SAMPLING rates for recording: 1.6 MHz and 2 MHz; both of them cover the full MW dial. Native Perseus package supports only one such sampling rate (2 MHz) with a full MW coverage; the same sampling rate of 2 MHz (SAMPLING 2000) is also available in JAGUAR. Use this sampling rate is you want to keep compatibility with Perseus.exe as far as the playback is concerned.

In addition to 2 MHz, JAGUAR PRO can also use the sampling rate of 1.6 MHz (SAMPLING 1600) which saves 20% of the disk space and lots of CPU/GPU cycles. The 1.6-MHz files cannot be played with Perseus.exe but they can be played with many third-party SDR software.

When the desired bandwidth has been defined, 80% of it is "alias-free", i.e. free from artifacts. The area outside of it can be tuned in to, but there may be also some "trash signals". For example, if you have selected SAMPLING 1600, your alias-free bandwidth is 1.28 MHz. If you use the center frequency of 1105 kHz, the alias-free band covers 465 kHz - 1745 kHz.

So, if you want to record both LW and MW, you must use SAMPLING 2000, yielding an alias-free bandwidth of 1600 kHz, and the center frequency of e.g. 1005 kHz will yield an alias-free frequency range of 205 kHz - 1805 kHz.

Note that it is recommended to use a center frequency which does not contain any broadcasting transmissions. This is because SDRs often generate an artificial peak on that frequency. This means that you will see a spectrum trace on that frequency even if you do not have any antenna connected.

HOW TO


Selecting the bandwidth of 2 MHz or 1.6 MHz.

The sampling rate is defined in SETTINGS > KIT > RECORDING > BANDWIDTH.

When you tune in to shortwaves in the LIVE mode, the center frequency is automatically set to be 10 kHz below the tuned frequency. The SAMPLING rate however remains the same.