| 摘要 |
PURPOSE:To obtain the converter in which a disturbing signal such as cross modulation and intermodulation product is not produced by throwing a changeover circuit to the position of an HPF circuit when a control voltage is a prescribed voltage or over. CONSTITUTION:When a selected station channel has a low channel selection frequency, since a control voltage Vt is low, a switching voltage being an output of a comparator 9 resulting from the comparison with a prescribed voltage Vref is at a low level, changeover circuits 4, 5 are set to the side of a terminal (a), and a broad band high frequency signal from a center is inputted to a variable LPF 6 directly via a through-path 2. When the channel selection frequency is high, since a control voltage Vt from a control voltage generator 10 commanded by data from a CPU 11 depending on the selected station channel is high, an output of the comparator 9 resulting from the comparison with the prescribed voltage Vref is at a high level, the changeover circuits 4, 5 are thrown to the position of a terminal (b). Then the high frequency signal from the center is inputted to an HPF circuit 3, from which a frequency component whose frequency is 300MHz or 400MHz or over is outputted. |
