Basic Marker Placement
In RF View, tap anywhere on a plotted trace to place a frequency marker. The marker displays:
- Frequency (Hz, kHz, MHz, or GHz)
- S-parameter magnitude (dB)
- S-parameter phase (degrees, if phase display is enabled)
- Impedance (R + jX in ohms, if Smith chart mode active)
Drag the marker left or right to move it along the trace. Double-tap to remove a marker.
Multiple Markers
RF View supports placing up to 4 simultaneous markers on a plot. Use multiple markers to:
- Mark the upper and lower −3 dB frequencies to read bandwidth directly
- Mark pass and stop band edge frequencies of a filter
- Identify the resonance minimum (deepest S11 dip) and second resonance
- Compare S21 at several spot frequencies simultaneously
Delta Marker
The delta marker (Δ) shows the difference between two markers:
- Frequency difference: Δf = f₂ − f₁ → bandwidth measurement
- Amplitude difference: ΔS21 = S21(f₂) − S21(f₁) → slope or ripple quantification
- Phase difference: Δφ → phase shift across a band
To activate: place two markers, then long-press the second to set it as delta reference. The display shows Δ values relative to the reference marker.
Minimum and Maximum Search
RF View has a minimum/maximum marker search function:
- Min search: Useful for finding the deepest S11 dip (antenna resonance, filter center)
- Max search: Useful for finding the peak S21 in a passband or worst-case S11
- Activate via long-press on the plot area and select "Find Min" or "Find Max"
Practical Measurement Examples
| Measurement | Marker Setup | Read Value |
|---|---|---|
| Filter 3 dB bandwidth | Min search + 2 markers at −3 dB crossing | Δf of two markers |
| Antenna resonance | Min search on S11 | Frequency at deepest dip |
| Passband insertion loss | Marker at band center | S21 value in dB |
| Stopband rejection | Markers in passband and stopband | ΔS21 between markers |
| Cable loss at specific freq | Single marker at target frequency | S21 magnitude |
Exporting Marker Data
After setting markers at key frequency points, RF View can export the marker table as a CSV file. This is useful for:
- Recording S-parameter values at specified test frequencies for data sheets
- Comparing measurements from multiple units at the same spot frequencies
- Creating production test reports with specific pass/fail criteria
The exported CSV includes frequency, magnitude, and phase for each marker across all loaded files — ideal for batch production testing documentation.