Analogue Standing Wave Meter Head, SWR Watt 4W/20W Range,Power for Electronic

**Core Structure & Pointer Specs** Adopts magneto electric system core structure. Pointer made of nickel foil copper connected aluminum hollow tube with carbon fiber black finish. Dimension: Length 51.0mm±0.5mm, Width 0.3mm±0.1mm. Pointer rests at zero calibration line on left & right scales under power-off status. **Housing & Accessories Material** Upper cover: ABS+PMMA; Lower cover: HIPS; Nameplate: Aluminum plate. No B board and light bulb equipped. Designed for vertical installation. **Electrical Parameters** Internal DC impedance: 1500Ω±10% Calibration Value Tolerance: ±5% Relative Error: ±5% Insulation Strength: ≥50MΩ (Tested with DC 500V between circuit and meter housing) **Precision & Mechanical Performance** - Mechanical zero position: Pointer aligns with zero scale center, tolerance ±1mm - Friction error: ±1mm - Balance error: ±1.5mm when tilted 45° forward, backward, clockwise & counterclockwise - Damping time: 2 ~ 3 seconds (2/3 full scale input) **Testing Standard & Overcurrent Resistance** Standard test environment: 20℃, 70%RH; testing available at normal room temperature if test result remains consistent. Overcurrent impact test: Apply 2× full-scale current instantaneously, maintain 7s then reduce to 1/2 full scale. Pointer shall recover within 1/2 full scale range after test.