Dukane-1A803-pwr-sch 电路图 维修手册.pdf

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1、EXTERNAL CONNECTIONS DUKANE MODEL 1A803 100-WATT POWER AMPLIFIER FUSE (A N D THERMOSTAT) - One 4-ampere slow-blow fuse protects the primary AC power circuit for this amplifier. I n addition,there is a temperature-controlled (thermostat) switch (S1) ) in the AC power circuit and which is fastened to

2、one of the large transistor heatsinks; any over-heating of the output transistors will open the primary : power circuit, and the power circuit is close d automaticallyy as the thermostat temperature comes INSTALLATION NOTES - The DuKane Model 1A803 100-Watt Power Amplifier provides input, single-end

3、ed. See paragraph titled “INPUT LEVEL” down. full-rated output with 0.4 volt on next page. Amplifier Ground - I t t is good practice to ground the amplifier chassis to the rack or console metalware which is, in turn, connected to conduit and electrical system ground (or coldwater pipe). To be sure g

4、rounding exists between the amplifier and the metal- ware, place an outside-toothed lockwasher under the head of one of the mounting screws. Clas s I I I wiring is permissible for 25-volt or 70-voltt level output (speaker line). A C power wiring must be Class I w i r i n g o n l y . EXTERNAL CONNECT

5、IONS - Make ALL external connections to screw terminals on rear of amplifier.Connect AC power to this amplifier AFTER external connections have been made and are checked to be free of any short circuits. A conventional speaker system of up to 100 watts,including appropriate speaker-to-line matching

6、transformers can be connected to this amplifier.See chart at top of next page. OUTPUT CONNECTIONS - I35 Connect jumper wires between screw terminals 25-VOLT OUTPUT and connect speaker line as shown at right 246 246 n 402-ig2A RadioFans.CN 收音机爱 好者资料库 - 70-VOLT SPEAKER LINE25-VOLT SPEAKER LINE SPEAKER

7、 POWER DUKANE TRANSFORMER SPEAKER POWERDUKANE TRANSFORMER LEVEL PART NO. LEVEL PART NO. 15 to 50 watts 710-3070 5 to 20 watts710-3077 5 to 30 watts 710-30711 / 2 2 to 2 watts710-3075 1 / 2 2 to 4 watts l/1 6 to l/2 watt INPUT LEVEL - Not more than 0.4 volt rms (sine wave) input is required to obtain

8、 full 100 watts of output power with this amplifier. , However,it is recommended that, in order to accommodate the complex wave form of program material,th e input should be lowered 8 dB (to 0 VU) for actual amplifier installation and operation.Set INPUT LEVEL potentiometer for 0 level indicated on

9、VU meter (on 25-volt line. IO volts rms sine wave - on 70-volt I ine, 28 volts rms). hput connections are made at screw terminals labeled “IN and “COM”, shield to “COM”. COM to GND -In some instances,it will be found desirable to disconnect the jumper be- tween “COM” and “GND” on the input terminal

10、strip - amplifier common connected through shield to preamplifier ground instead - to reduce any hum pick-up.ALSO see paragraph on the front of this sheet titled “Amplifier Ground”. BRIDGE IN COM GNO DC II OUTPUT HIGH-IM PEDANCE INPUT C ONNE CTIONS. BRIDGING -An appropriate resistor may be connected

11、 between the screw terminals labeled “BRIDGE” and “IN ” in instances where input level is too high to be easily reduced by INPUT LEVEL potnitometer.A lOO,OOO-ohm, l/2-watt resistor will reduce input level by 6 dB; a I-megohm resistor would be inserted where input might exceed 10 volts. AC POWER CONN

12、ECTIONS - IMPORTANT -Before connecting AC power to this amplifier, BE SURE that correct output load (speakers correctly matched to speaker line) and input connections are properly made to terminals on this amplifier. AC power wiring must be Class I wiring ONLY. primary taps for IlO-volt line, Power

13、transformer in this amplifier has 117-“online and 125-volt line. As supplied. the 117- volt tap is connected.However,if line voltage is more than 120 volts, disconnect the circuit breaker white wire connected at terminal lug for yellow-black transformer tap, and connect circuit breaker wire to lug for red-black transformer tap.If line voltage is less than Ii 5 volts,connect circuit breaker wire to white-black transformer tap. DC TERMINAL -Auxiliary power is available for external preamplifie,r, of 28 volts DC at 50 milliamperes. a RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库