| 摘要 |
The transmitter delivers signals with a wide frequency spectrum, the intervals between the frequency channels being rather small. The transmit filter (1) has relatively numerous, exclusively band pass circuits (K1-6) for safeguarding the required steepness of the filter characteristic flanks and a high clearance of all other frequencies. The band pass circuits are mfd. by milling from a material block by an NC machine tool for attaining the mechanical precision, avoiding the need for fine tuning of the transmit filter. Pref. the band pass circuits are milled from a brass block. |
