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This page is designed to convert between different 2 port specification and can also do some calculation on a 2 port circuit. It is possible to select between letters and number syntax and select with and without complex values.

Parameters can be specied in any of these formats (with a few exceptions) and express exactly the same behavior.

It is also possible to select a circuit and have it converted to a two port representation and draw a curve of some circuit parameters dependency on frequence.

- Impedance (Z)
- Admittance (Y)
- Hybrid (H) often used for LF transistors
- Inverse hybrid (G) gf for a mos transistor
- Transmission (A) (ABCD) (T)
- Inverse transmission (B) (S)

Model type | Select model displayet and used for output result |

Input model | Model used for input parameters |

Z/Y/H/G/A/B | First used to designate model in parameters |

i or 11 | Input parameter |

r or 12 | Reverse parameter, how signal on output affects input |

f or 21 | Forward parameter, how signal on input affects output (i.e. Hfe is hybrid model, forward(gain) in commen emitter circuit) |

o or 22 | Output parameter |

i or P | imaginary part or Phase angle of value |

Source Z | Impedance of source circuit |

Load Z | Impedance of load circuit |

Input U | Voltage from source circuit |

Curve | Opens the "Curve plotter page" and show the frequence response of the defined circuit. This selection will only be available when a circuit is selected, Source Z and Load Z are real values |

Letters | When checked the i/r/f/o indices are used, else 11/12/21/22 indices are used |

Complex | When checked all input can be complex numbers. Output will display complex values when required. |

Phase input | When checked specify all input values as phase angle |

Phase output | When checked all complex output is shown as phase angle |

Formulas | Formulas are show for both input and output models |

Z/Y/H/G/A/B | The parameters from the input model converted to the output model Source/load values are ignored |

Zin | Input impedance of model when output is unloaded |

Zout | Output impedance of model when input unconnected |

Gain | Voltage/current gain when output unloaded/shorted |

Revers | Voltage/current revers (output to input) gain when input unloaded/shorted) |

Zi | Input impedance of model when using specifed Zout |

Zout | Output impedance of model when using specified Zin |

Av | Voltage gain of model when using specified Zout, based on voltage at input terminals |

Ai | Curret gain of model when using specified Zout, based on current into input terminals |

Vi | Voltage at input terminal when supplying "Input U" from specified "Source Z" and output is loaded with "Load Z" |

Ii | Current into input terminal when supplying "Input U" from specified "Source Z" and output is loaded with "Load Z" |

Vo | Voltage at output terminal when supplying "Input U" from specified "Source Z" and output is loaded with "Load Z" |

Io | Current into output terminal when supplying "Input U" from specified "Source Z" and output is loaded with "Load Z" |

Only used for "Transmission" and "Inverse transmission" model, because parameters are some times called ABCD/EFGH and not the usual names.

- T
- PI

- Parameters with the value 0 can not be converted between all models, i.e. 0 ohm is very difficult to express as conductance
- Some other conditions can also prevent conversion between some models
- Many calculations are done with formulas appropriate to the selected models, this avoids problems with impossible model conversions
- To break a connection in a T or PI circuit, use a very large resistor

- 1 order filter can design filters
- Serial/parallel can be used to make non-standard component values