Kenwood TH-D72A Service Manual

Also see for TH-D72A: Instruction manual User manual Instruction manual Instruction manual Instruction manual

Contents

TH-D72A/D72E41. OutlineThe TH-D72A/D72E is an FM Dual Band (A: 144/440MHz/E: 144/430MHz) handheld transceiver designed to be usedas an Amateur Radio.2. Frequency ConfigurationThis equipment has an individual VCO/PLL and IF circuitfor both Band A and B. Using these circuits, it can receive2 separate bands and can transmit and receive at the sametime.The VCO of Band A is used for the first-local oscillator forVHF/UHF reception of Band A. The VCO of Band B is usedfor VHF/UHF transmission with modulator by 2-VCOs andfor the first-local oscillator for VHF/UHF reception of Band B.The reference oscillator of 16.8MHz connected witheach PLL IC for Band A and B are used as the comparisonfrequency at each PLL IC. The reference oscillator of BandA is generated three times to 50.400MHz and is used forthe second-local oscillator for the reception of Band A. Thesecond-local oscillator for the reception of Band B uses thecrystal oscillator of 45.505MHz.Figure 1 Frequency configurationTH-D72A (K-type) TH-D72E (E-type)A 144.000 ~ 147.995MHz 144.000 ~ 145.995MHzB 438.000 ~ 449.995MHz 430.000 ~ 439.995MHzC 189.050 ~ 193.045MHz 189.050 ~ 191.045MHzD 392.950 ~ 404.945MHz 384.950 ~ 394.945MHzE 193.950 ~ 197.945MHz 193.950 ~ 195.945MHzF 388.050 ~ 400.045MHz 380.050 ~ 390.045MHzTable 1 Frequency configurationx3x250.400MHz49.950MHz FEABABABBand AUHF RXBand BUHF RXBand AVHF RXBand BVHF RXCDVHF TXUHF TXBand BPLLMICAMPAFAMP16.800MHz16.800MHz45.505MHz45.050MHzBand BDemodulatorBand ADemodulator455kHz450kHzBand APLLCIRCUIT DESCRIPTION