VT-183 WARNING The following instructions are for use by qualified personnel only. To avoid electric shock, do not perform any servicing other than contained in the operating instructions unless you are qualified to do so. CONTENTS SPECIFICATIONS ......................3 SAFETY ..........................4 CIRCUIT DESCRIPTION ....................5...
VT-183 SPECIFICATIONS Meter Section Measure voltages 1mV to 300mV in 12 ranges : 1, 3, 10, 30, 100, 300mV, 1, 3, 10, 30, 100, 300V full scale –80 to +50dB (0dB=1V) –80 to +52dBm (0dBm=1mW at 600Ω) Error Within ±3% of full scale at 1kHz Frequency response ±10% at 5Hz to 1MHz,...
VT-183 SAFETY SAFETY Line fuse Before connecting the instrument to a power source, care- The fuse holder is located on the rear panel and contains fully read the following information, then verify that the the line fuse. Verify that the proper fuse is installed by proper power cord is used and the proper line fuse is replacing the line fuse.
VT-183 CIRCUIT DESCRIPTION In studying the operation of each circuit in voltmeter please refer to "BLOCK DIAGRAM". General 7) Absolute-Mean Valve Detector This AC voltmeter is combined with Meter unit and Control An absolute-mean value detector comprised of a high unit.
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VT-183 CIRCUIT DESCRIPTION 6) Differentiator The oscillator output will pass through a RC differentiator and then active the discharge circuit. 7) Up Comparator The Up comparator will output a Up pulse when the output of the peak hold regulation circuit is higher than the high ref- erence voltage.
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INPUT OUTPUT-1 IMPEDANCE OUTPUT 1st ATT 2nd ATT 3rd ATT MAIN AMP CONVERTER RELATIVE REF. ABSOLUTE REMATE POWER MEAN INPUT CONTROL SUPPLY VALUE DET METER DC±5V INPUT BD. AC 100V/120V/220V/230V POWER POWER 50/60Hz TRANSFORMER ON/OFF DC±5V PEAK HOLD UP/DOWN PRE AMP DECODER REGULATOR COMPARATOR...
VT-183 ADJUSTMENT To obtain the best performance, periodically calibrate the PREPARATION FOR ADJUSTMENT unit. Sometimes, only one mode need to be calibrated, while Control Settings at other times, all modes should be calibrated. When one The control settings listed below must be used for each mode is calibrated, it must be noted that the other modes adjustment procedure.
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VT-183 ADJUSTMENT ITEM ADJUSTMENT POINT PROCEDURE 1V range VR101 RANGE: 1V 1) Input 1kHz (or 400 Hz), 1 Vrms sine wave, and set the pointer to 10.0 V of the 0- 10 scale. Check that the variable range is less than 98% and more than 102% with respect to 10.0 (full-scale).
Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No. werden nicht geliefert. Add- Parts No. Ref. No Description ress VT-183 A01-4087-08 CASE;TOP A01-4089-08 CASE;BOTTOM A13-2254-08 SIDE FRAME A22-1345-08...
* New Parts * New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
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* New Parts * New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.
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* New Parts * New Parts Parts without Parts No. are not supplied. Parts without Parts No. are not supplied. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Les articles non mentionnes dans le Parts No. ne sont pas fournis. Teile ohne Parts No.