Overview The TS-450S/690S series consists of the following models: • TS-450S with AT (For HF) - TS-450S without AT (For HF) • TS-690S without AT (For HF plus 50-MHz band) (An optional AT can be built in.) The receive frequency range is 100kHz to 40MHz for the TS-450S, and 100kHz to 60MHz for the TS-690S. (For the performance guarantee range, see the ratings.) The local oscillator system uses a DDS (direct digital synthesizer) with a 1 Hz resolution and the stability of single-crystal frequency management. 1) Features • Primary operation mode in which the minimum panel functions necessary for transmission are available ‘ ■ High receive performance by triple conversion • Optional filters (8.83MHz x 2, 455kHz x 1) ■ High receive sensitivity in the 28 and 50MHz bands (AIP off) • High intercept point in the 28MHz and 50MHz bands (AIP on) • Switches, such as AIP and AGC, are controlled by the microcomputer, and can be memorized. • NB2 is built in. • The DSP-100 and AT-300 can be connected.