Kenwood TS-590SG Manual

Also see for TS-590SG: Reference guide Setting manual Setting manual Instruction manual Instruction manual

Contents

01 RECEPTION4Figure 1-1 Dual-mode Conversion Frequency ConfigurationFirst, let us begin with explanation about the up-conversion path.In the up-conversion path, double-headed arrows are shown at each stage pointing in both directions. This means a transmitsignal as well as a receive signal is processed in the up-conversion path. The circuit configuration is a triple-conversiondesign featuring an IF DSP, a typical configuration for an HF transceiver. (Replacing the IF DSP with an AF DSP and thethird Mixer with a modulator and demodulator changes it to be the configuration of TS-480HX/SAT.)The pass bandwidth of the filter is about 15 kHz at 73.095 MHz, and at 10.695 MHz, it varies depending on the mode andthe RX bandwidth. In CW, SSB and FSK modes, the bandwidth is 2.7 kHz, in AM mode 6 kHz, and in FM mode 15 kHz.The modulated transmit signal passes through the 6 kHz band pass filter except during FM mode. The final bandwidth isdetermined by the DSP. The local oscillator signal of the last outgoing mixer is FM modulated in the FM mode, and doesnot affect the pass bandwidth of this filter.The up-conversion path is applied only in conditions when no down-conversion path is used.Next is the down-conversion path.In the down-conversion path, only a single-ended arrow is shown at each stage. This means the down-conversion operationis applied only to RX signals.Also, in the figure the conditions in which the down conversion operates are described. These conditions are designed tocover the bands, modes and bandwidths that are commonly used in a contest and on similar occasions.On the surface, the circuit configuration may seem too complex and wasteful. Still, due to the frequency configuration thatfocuses on particular points, the general coverage reception across the continuous frequency range of 30 kHz through 60MHz covered by the VFO is maintained as on previous models. As a result, we have successfully produced a transceiverin a competitive price range that achieves excellent receive performance comparable to the high-end HF transceivers onthe market.As for the up-conversion path, though the same frequency configuration is used as in the previous models, the roofingfilters have been improved to have better characteristics to protect against interference within the pass bandwidth. Fordetails, refer to 1.3 Up-Conversion.