Transponder Frequency Calculator

Calculate optimal frequencies for 125kHz/433MHz transponder systems

Calculate transponder frequency parameters for motorcycle key systems. Determine effective transmission distance and power requirements based on carrier frequency and modulation depth for optimal performance.

Input Parameters

433MHz is the most common frequency for motorcycle key fobs
Industry standard: 30-80% (50% provides optimal balance)
Typical motorcycle key: 5-15 dBm (10 dBm is standard)
Urban environment is typical for motorcycle usage

Calculation Results (Industry Standard Example)

Maximum Transmission Range
15.2
meters
Power Requirement
5.0
mW
Wavelength
0.692
meters
Transmission Efficiency
30.0
%
These are example results based on industry standard values. Click "Calculate Parameters" to get results for your specific inputs.

Calculation Formulas

Maximum Range Calculation:

Range = √(P_tx × G_tx × G_rx × λ²) / (16π² × P_rx_min) × Environment_Factor

Power Requirement:

P_req = P_tx × (Modulation_Depth / 100) × Efficiency_Factor

Wavelength:

λ = c / f (where c = 3×10⁸ m/s)

Frequently Asked Questions

What frequency should I use for my motorcycle key?

125kHz is commonly used for proximity keys, while 433MHz is used for remote key fobs. The choice depends on your specific application and regulatory requirements.

How does modulation depth affect performance?

Higher modulation depth improves signal clarity but requires more power. Typical values range from 30-80% depending on the application requirements.

What factors affect transmission range?

Transmission range is affected by frequency, power output, antenna design, environmental conditions, and interference from other devices.