Summary of Contents for PRESIDENT JOHNNY III ASC 12/24
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JOHNNY III HARRY III ASC 12/24 SERVICE MANUAL...
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-TECNNICAL CHARACTERITICS JOHNNY III ASC 12/24 ( config: EU PL d In ) 1-GENERAL: -Multiconfiguration (EU, PL, d, In) -EU 40 channels AM 4W (from 26,965Mhz to 27,405Mhz) -PL 40 channels AM 4W (from 26,960Mhz to 27,400Mhz) -d 40 channels AM 4W (from 26,965Mhz to 27,405Mhz) -In ...
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3-RECEPTION: -Maximum sensitivity at 20dB sinad -0,5µV(-113dBm) AM -Audio frequency response -From 300Hz to 3kHz in AM -Adjacent channel selectivity -Superior to 60dB -Frequency image rejection -Superior to 60dB -Intermodulation response -Superior to 54dB -Maximum audio power -Squelch sensitivity -Threshold 0,2µV(-120dBm)/Tight 1mV(-47dBm) -Current drain -300mA nominal/600mA maximum...
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-TECNNICAL CHARACTERITICS HARRY III ASC 12/24 ( config: EU PL d EC U In ) 1-GENERAL: -Multiconfiguration (EU, PL, d, EC, U, In) -EU 40 channels AM/FM 4W (from 26,965Mhz to 27,405Mhz) -PL 40 channels AM/FM 4W (from 26,960Mhz to 27,400Mhz) -d ...
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3-RECEPTION: -Maximum sensitivity at 20dB sinad -0,5µV(-113dBm) AM/FM -Audio frequency response -From 300Hz to 3kHz in AM/FM -Adjacent channel selectivity -Superior to 60dB -Frequency image rejection -Superior to 60dB -Intermodulation response -Superior to 54dB -Maximum audio power -Squelch sensitivity -Threshold 0,2µV(-120dBm)/Tight 1mV(-47dBm) -Current drain -300mA nominal/600mA maximum...
ALIGNMENT PROCEDURE (JOHNNY III ASC 12/24) (HARRY III ASC 12/24) * VCO/PLL PORTION - Alignment procedure - Test points - Frequencies chart * TRANSMITTER - Alignment procedure - Test points * RECEIVER - Alignment procedure - Test points Test equipement required...
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ALIGNMENT VCO/PLL 1 - Alignment procedure (13,2V/26,4V;configuration”EU”) STEP CONDITION ADJUSTMENT REMARKS OF ADJUSTMENT FM(UK Eng) RT301 Connect a frequency counter to TP200, RX mode and adjust RT301 to reach Channel 20 38,48625MHz. AM/FM(EU) RT302 Connect a frequency counter to TP200, RX mode and adjust RT302 to reach Channel 20...
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ALIGNMENT TRANSMITTER 1 - Alignment procedure (13,2V/26,4V;configuration”EU”) STEP CONDITION ADJUSTMENT REMARKS OF ADJUSTMENT AM/FM(EU)TX RT402 Connect a wattmeter to jack antenna, Channel 20 adjust RT402 to reach 4W on the wattmeter. Same as 1 Connect a dummy load to jack antenna. Check that the “RF meter”...
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ALIGNMENT RECEIVER 1 - Alignment procedure (13,2V/26,4V;configuration”EU”) STEP CONDITION ADJUSTMENT REMARKS OF ADJUSTMENT AM(EU) Connect HF generator to jack antenna Channel 20 adjusted at ( –107dBm 1KHz 60%), Middle volume connect sinad meter to jack EXT speaker level. and check that the sensitivity ( ...
UNIDEN CORP. CIRCUIT DESCRIPTION Model: JOHNNY III 12/24 V 1. FREQUENCY SYNTHESIZER Both of TX and RX local frequencies are generated by means of a phase locked loop frequency synthesizer. These frequencies are directly obtained from VCO (Voltage Controlled Oscillator). A 10.240MHz Crystal oscillator is provided as a reference frequency that is divided by 2048 in order to produce 5kHz of basic value for the 10kHz channel spacing.
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BLOCK DIAGRAM (Ver.1) JOHNNY III 12/24 V (UT404AV) SQ VOL ASC AGC SQVOL HICUT RF VOL CONT SQ AMP AGC AMP AGC DET HI CUT NOISE AMP NOISE DET GATE 27MHz 10.695MHz 10.695MHz 455kHz VOLUME D1,D2 Q2,Q3 Ceramic IF AMP IF AMP RF ATT RF AMP...
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UNIDEN CORP. CIRCUIT DESCRIPTION Model: HARRY III 12/24 V 1. FREQUENCY SYNTHESIZER Both of TX and RX local frequencies are generated by means of a phase locked loop frequency synthesizer. These frequencies are directly obtained from VCO (Voltage Controlled Oscillator). A 10.240MHz Crystal oscillator is provided as a reference frequency that is divided by 2048 in order to produce 5kHz of basic value for the 10kHz channel spacing.
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BLOCK DIAGRAM (Ver.1) HARRY III 12/24 V (UT404ZV) SQ VOL ASC AGC SQVOL RFgain VOL HICUT CONT SQ AMP AGC AMP AGC DET HI CUT NOISE AMP NOISE DET GATE 27MHz 10.695MHz 10.695MHz 455kHz VOLUME D1,D2 Q2,Q3 Ceramic IF AMP IF AMP RF ATT RF AMP...
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JOHNNY III ASC HARRY III ASC 12/24 SCHEMATIC DIAGRAM...
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JOHNNY III ASC HARRY III ASC 12/24 COMPONENT LAYOUT...
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JOHNNY III ASC HARRY III ASC 12/24 COMPONENTS LIST...
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