Struct PentodeRoot 

pub struct PentodeRoot {
    pub model: PentodeModel,
    /* private fields */
}

Pentode nonlinear root for WDF trees.

Models the plate-cathode path as a nonlinear element controlled by an external control grid voltage (Vg1k) and screen grid voltage (Vg2k). Uses Newton-Raphson to solve the implicit WDF constraint equation.

The plate current follows a screen-referenced Koren model with an atan-based plate saturation term, accurately capturing the pentode’s nearly flat plate curves in the saturation region.

Pins: .grid (control grid g1), .screen (screen grid g2), .plate, .cathode

Fields

model: PentodeModel

Implementations

impl PentodeRoot

pub fn new(model: PentodeModel) -> PentodeRoot

pub fn new_with_v_max(model: PentodeModel, v_max: f64) -> PentodeRoot

Create a pentode root with a specific supply voltage (B+).

pub fn set_v_max(&mut self, v_max: f64)

Set the maximum plate voltage (B+ supply rail).

For tube circuits, the plate voltage can swing from 0V (tube saturated) to B+ (tube in cutoff). This sets the upper bound for Newton-Raphson.

pub fn v_max(&self) -> f64

Get the current v_max setting.

pub fn set_bias(&mut self, vg1k_bias: f64)

Set the DC bias operating point from circuit analysis.

pub fn vg1k_bias(&self) -> f64

Get the DC bias operating point.

pub fn set_vg1k(&mut self, vg1k: f64)

Set the control grid voltage (g1-cathode). External modulation.

pub fn vg1k(&self) -> f64

Get current control grid voltage.

pub fn set_vg2k(&mut self, vg2k: f64)

Set the screen grid voltage (g2-cathode). Usually fixed at the operating point, but can be modulated for sag effects.

pub fn vg2k(&self) -> f64

Get current screen grid voltage.

pub fn plate_current(&self, vpk: f64) -> f64

Compute plate current for given Vpk at current Vg1k and Vg2k.

Screen-referenced Koren model:

E1 = Kp * (1/mu + Vg1k/Vg2k)
Ip_base = (Vg2k/Kp * ln(1 + exp(E1)))^Ex
Ip = (Ip_base / KG1) * atan(Vpk / KVB)

Trait Implementations

impl Clone for PentodeRoot

fn clone(&self) -> PentodeRoot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for PentodeRoot

impl Debug for PentodeRoot

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl NlDeviceIv for PentodeRoot

fn iv(&self, v: f64) -> (f64, f64)

Return (current, d_current/d_voltage) at the given port voltage.

fn v_clamp(&self) -> (f64, f64)

Return (v_min, v_max) voltage clamping bounds for this device.

impl WdfRoot for PentodeRoot

fn process(&mut self, a: f64, rp: f64) -> f64

Pentode plate-cathode path: i = Ip(Vpk, Vg1k, Vg2k)