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40 ‐ Spectrum analyzer

ErikS-web edited this page Feb 2, 2024 · 72 revisions

Additions: Extra functionality


Some mods introduced by me on the spectrum functionality.

  • Spectrum channel scan mode enter by going into memory mode and press F+5, this allows SUPER fast channel scanning (4.5x faster than regular scanning).

    Regular scan of 200 memory channels takes roughly 18 seconds, spectrum memory scan takes roughly 4 seconds, if you have less channels stored i.e 50 - the spectrum memory scan will take only 1 second.

  • Show channel number and channel name of the peak frequency in spectrum

  • Pressing PTT exits the spectrum and fine tuning screen and copy current peak frequency, modulation, step, bandwidth to VFO. Also entering spectrum will carry these settings from VFO (full integration). Now to enter fine tuning screen in spectrum press MENU. This allows you to save and respond to the frequencies found much faster.

  • Green RX LED turns on in spectrum only when BlMax > 7, to improve user experience in low light conditions

  • Squelch Tail tone Elimination works in spectrum (if matches settings in menu-SqTone )

  • Mode indicators ( top-left of the screen and and bottom center )

    • N(0x) - normalization function applied indicator
    • ATT - attenuation applied indicator
    • BL - blacklist applied indicator

    These functions

    • are available in all spectrum-modes (channel/frequency/scan range)
    • reset when switching in spectrum mode
  • Attenuate function

    • sometimes there is a channel that has some interference, opening squelch randomly etc., before we had to either blacklist such channel or move the squelch threshold line higher, with this feature we can just attenuate particular channel
    • in order to use it press FN2 when RX is on, it will apply attenuation to the currently listened channel. You'll see a ATT indicator at the bottom of the screen.

Note

  • attenuate usage has been simplified so now it can be applied anytime to current peak bar
  • when a spectrum scan has more than 128x samples, the spectrum attenuate function cannot be activated (to prevent errors)

  • Normalization auto-adjusts screen, when activated. N(0x) on screen

Button functions

  • In Memory Channel mode press F+5 to enter SUPER FAST spectrum channel mode
  • In VFO-mode long press 5 to enter scan range mode (ScnRng on display)
  • In VFO-mode long press 5 then press F+5 to enter spectrum scan range mode
  • 2 toggles spectrum channel mode normalization function, that brings up all of the RSSI readings to the peak value. Resolves the 'valley problem' with channels hiding behind other channels of higher noise floor
    • To use it, wait until there are no active TX peaks across the whole spectrum and press 2
    • To turn it off press 2 again or use the reset blacklist UP/DOWN buttons
  • 3 / 9 vertical scale; adjusts the scaling of the spectrums (y-axis) between -130 and 10 dB (default is 50 dB). The value is displayed in the top left part of the screen.
  • 4 toggles scanlist SL I, SL 2, All. This can be actually useful to have different scanlists for different modulations, as spectrum channel scan uses single modulation for the whole scan.
  • 6 toggles the bandwidth between 5, 6.25, 8.33, 12.5 and 25 kHz
  • 8 backlight toggle
  • * and F adjusts the squelch level which is represented by the dotted line.
  • FN1 will put the current peak channel on the BlackList. You'll see a BL indicator at the bottom of the screen.
  • FN2 will apply Attenuation to the current peak channel. You'll see a ATT indicator at the bottom of the screen.

Spectrum Sweep screen


Press F+ 5 to enter the spectrum mode of the Spectrum analyzer.

The current VFO/Memory frequency will be the start frequency of the spectrum sweep


  • spectrum frequency change step is auto-adjusted to half a spectrum bandwidth
  • Spectrum analyzer can also be used with ScnRng mode

Note

  • in this mode Blacklist is limited to 200 frequencies

Button functions

  • 1 / 7 - increases/decreases frequency step between consecutive bars
  • 2 - normalization function (don't press until no active TX peaks in spectrum)
  • 4 -
    • From VFO-mode: toggles the number of bars (channels) in the graph.
    • From Memory-channel-mode: toggles scanlist SL I, SL 2, All.
  • 5 - shows a frequency input box for lower sweep frequency (value in MHz, * - decimal point)
  • 3 / 9 vertical scale; adjusts the scaling of the spectrums (y-axis) between -130 and 10 dB (default is 50 dB). The value is displayed in the top left part of the screen.
  • 6 - toggles receiver bandwidth
  • 8 - toggle backlight
  • * / F - increase/decreases squelch level
  • 0 - toggles modulation type (FM/AM/USB)
  • Side Button I - _excludes _current frequency in the spectrum scan (add to blacklist). You'll see a BL indicator at the bottom of the screen.
  • Side Button II - Attenuation to the currently listened channel. You'll see a ATT indicator at the bottom of the screen.
  • UP and DOWN keys in spectrum channel mode now resets the exclude frequencylist (blacklist) and normalization function
  • Menu to enter fine tuning mode (see Detail Monitor Screen)
  • EXIT - exits to the previous screen/function
  • PTT - will copy current modulation, step, frequency, bw and enter VFO mode

Detail Monitor screen

Button functions

M - scrolls through the parameters displayed at the bottom of the screen which can be adjusted with UP/DOWN

  • LNA$ - Low Noise Amplifier $hort
  • LNA - Low Noise Amplifier
  • PGA - Programmable Gain Amplifier
  • MIX - MIXER Gain

  • EXIT - exits to the previous screen of the spectrum analyzer

Documentation


Note

  • When spectrum analyzer is active, you cannot communicate with Chirp