TB8100 Service Manual Reciter Circuit Description 27© Tait Electronics Limited September 20062 Reciter Circuit DescriptionThis chapter describes the circuitry used in VHF and UHF reciters. Muchof this circuitry is common to both frequency bands, and is thereforecovered by a single description in this chapter. Where the circuitry differsbetween VHF and UHF, separate descriptions are provided for eachfrequency band. In some cases the descriptions refer to specific VHF orUHF bands or sub-bands, and these are identified with the letters listed inthe following table (refer to “Identifying the Reciter” on page 70 for moredetails).The reciter comprises three boards: an RF board, a digital board, and anoptional system interface board. These boards are mounted on a centralchassis/heatsink. Figure 2.1 on page 28 shows the configuration of the maincircuit blocks, and the main inputs and outputs for power, RF and controlsignals. The locations of the main circuit blocks on the boards are shown inFigure 2.14 on page 61, Figure 2.15 on page 63, Figure 2.16 on page 65,and Figure 2.17 on page 67.FrequencyIdentification Frequency Band and Sub-bandVHFB band B2 = 136MHz to 156MHzB3 = 148MHz to 174MHzC band C1 = 174MHz to 193MHzC2 = 193MHz to 225MHzUHFH band H1 = 400MHz to 440MHzH2 = 440MHz to 480MHzH3 = 470MHz to 520MHzH4 = 380MHz to 420MHzK band K4 = 762MHz to 870MHzaa. The actual frequency coverage in this band is:Transmit: 762MHz to 776MHz, and 850MHz to 870MHzReceive: 792MHz to 824MHzL Band L1 = 852MHz to 854MHz, and 928MHz to 930MHzL2 = 896MHz to 902MHz (receive only)L2 = 927MHz to 941MHz (transmit only)
