Oscilloscope displays
Alongside the spectra and waterfalls, Linrad has three time-domain oscilloscopes, each tapping the signal chain at a different point. All three are expert-mode displays, toggled from the graph they belong to. They show the actual waveform — useful for judging impulse noise, AGC behaviour and coherent detection that the averaged spectra hide.
| Scope | Where | Shows | Toggle / state |
|---|---|---|---|
| Blanker (timf2) | high-resolution graph | the wideband timf2 time function and the noise blanker acting on it |
hg.timf2_oscilloscope (7 display states) |
| Baseband | baseband graph | the baseband time function after the audio filter | bg.oscill_on, gain bg.oscill_gain |
| Coherent | coherent graph | the coherent time traces (I/Q and recovered carrier) | cg.oscill_on |
The blanker oscilloscope is described on the noise blankers page — it is where the pulse-fitting blanker's work is visible. The baseband oscilloscope shows what reaches the demodulator, with its own gain control. The coherent oscilloscope shows the traces built for coherent detection, so the synchronous/binaural output can be seen as well as heard.
In the source
Blanker/timf2 scope: hg.timf2_oscilloscope toggled by HG_TIMF2_STATUS (hires_graph.c:501, cycling 0–6), fed by the timf2_oscilloscope_* state set up in buf.c and the oscilloscope-max pick in blank1.c:1004. Baseband scope: BG_OSCILLOSCOPE toggles bg.oscill_on baseb_graph.c:2541, BG_OSC_INCREASE / BG_OSC_DECREASE scale bg.oscill_gain. Coherent scope: CG_OSCILLOSCOPE toggles cg.oscill_on coherent.c:548; the traces are drawn in coh_osc.c (update_cg_traces() coh_osc.c:45, make_cg_trace() coh_osc.c:88). All three require OPERATOR_SKIL_EXPERT.
Related#
The blanker scope belongs to the noise blankers; the baseband scope to the baseband graph in the mixers/baseband chain; the coherent scope to the coherent output modes and coherent CW.