Heathkit Model ig-1272 Audio Generator
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- Bu səhifədəki naviqasiya:
- * * * * * * * CALIBRATION
- * * * * * * * FUNCTIONAL CHECKS
- Attenuator Switches and External Load Switch Check
| Heathkit Model IG-1272
Audio Generator
Date Calibrated: _____/_____/_____ Calibration Procedure
With the power supply off, the meter pointer should be over the zero reading on the meter face. If it is not, turn the mechanical zero-adjust screw at the bottom of the meter until the pointer is properly aligned. Disconnect all external cables, components, and wires from the output terminals. Ancillary Equipment Needed
AC VTVM (analog) 25 MHz Oscilloscope 50 coax cable (RG-58) Frequency Counter High Impedance VTVM Distortion Analyzer (optional)
Refer to PICTORIAL 4-2 Illustration Booklet, page 7
( ) Adjust the LEVEL control counter-clockwise to the OFF position. ( ) Set the X100 MULTIPLIER pushbutton to the ON (in) position.
( ) Set the 10 pushbutton of the 0–90 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position. ( ) Set the 10 ATTENUATOR pushbutton to the OFF (out) position.
( ) Set the 20 ATTENUATOR pushbutton to the OFF (out) position. ( ) Set the 40 ATTENUATOR pushbutton to the OFF (out) position.
( ) Set the EXT LOAD pushbutton in the OFF (out) position. * * * * * * * CIRCUIT BOARD INITIAL SETUP Refer to PICTORIAL 4-3 Illustration Booklet, page 7
( ) Adjust the METER ADJ control [R132] to the center of rotation. ( ) Adjust the DIST ADJ control [R109] to the center of rotation.
( ) Adjust the X1000 ADJ control [R107] to the center of rotation. ( ) Adjust the BIAS ADJ control [R112] to the 10 o’clock position.
( ) Adjust the FREQ ADJ trimmer [C101] to the center of rotation. (Position the notch as shown in the PICTORIAL.)
CALIBRATION
( ) Connect the line cord to the AC power line. ( ) Adjust the LEVEL control clockwise until the click. (Pilot lamp should light.)
( ) Adjust the LEVEL control to maximum clockwise. ( ) Adjust the METER ADJ control [R132] counter-clockwise until the meter indicates full scale on the 10-volt scale.
Oscilloscope Setup
( ) Set the oscilloscope’s vertical attenuator for a 40-volt input signal. If the oscilloscope will not display a 40-volt signal, use a X10 attenuator probe. DO NOT readjust the Generator’s LEVEL control.
( ) Set the oscilloscope’s horizontal sweep for a 1000 Hz [1 ms] signal. ( ) Connect a coax cable to the oscilloscope’s vertical input.
Generator Setup
( ) Set the X1000 MULTIPLIER pushbutton to the ON (in) position. ( ) Set the 10 pushbutton of the 0–90 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position.
( ) Set the EXT LOAD pushbutton in the OFF (out) position. ( ) Adjust the LEVEL control to maximum clockwise.
( ) Connect the same coax cable to the 10V OUT output jack of the generator. ( ) Adjust the DIST ADJ control [R109] until the oscilloscope’s trace is just clipping on both peaks of the waveform.
( ) Adjust the BIAS ADJ control [R112] for symmetrical clipping of the trace. ( ) Adjust the DIST ADJ control [R109] until the clipping just disappears.
( ) Adjust the LEVEL control to the maximum counter-clockwise OFF position. ( ) Disconnect the oscilloscope from the generator. * * * * * * * AC VTVM setup Refer to PICTORIAL 4-3 & 4-5 Illustration Booklet, pages 7 & 8
( ) Set the AC VTVM on the 10-volt scale. ( ) Connect a coax cable, or a set of test leads, to the AC VTVM’s input jacks.
( ) Connect the same coax cable, or set of test leads, to the 10V OUT output jack of the generator. ( ) Set the X100 MULTIPLIER pushbutton to the ON (in) position.
( ) Set the 10 pushbutton of the 0–90 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position. ( ) Adjust the LEVEL control to maximum clockwise.
( ) Adjust the DIST ADJ control [R109] for a 10-volt AC VTVM reading. ( ) Adjust the METER ADJ control [R132] for a 10-volt front panel indication.
( ) Set the X1000 MULTIPLIER pushbutton to the ON (in) position. ( ) Adjust the X1000 ADJ control [R107] until the front panel meter indicates full scale on the 10-volt scale.
( ) Disconnect the AC VTVM from the generator. * * * * * * * Oscilloscope setup
( ) Connect the oscilloscope the same as above. ( ) Set the 90 pushbutton of the 0–90 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position.
( ) Adjust the LEVEL control to maximum clockwise. ( ) Observe the oscilloscope’s trace for clipping.
( ) Adjust the BIAS control [R112] for either no clipping or symmetrical clipping. ( ) Adjust the LEVEL control to the maximum counter-clockwise OFF position.
( ) Disconnect the oscilloscope from the generator. * * * * * * * HIGH FREQUENCY CALIBRATION Frequency Counter setup
( ) Connect a coax cable to the frequency counter. ( ) Connect the same coax cable to the 10V OUT output jack of the generator.
( ) Set the X1000 MULTIPLIER pushbutton to the ON (in) position. ( ) Set the 0 pushbutton of the 0–90 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position.
( ) Adjust the LEVEL control to maximum clockwise. ( ) Adjust the FREQ ADJ trimmer [C101] for a Frequency Counter reading of 90 kHz +/- 2 kHz. * * * * * * * FUNCTIONAL CHECKS
( ) Set the 0 pushbutton of the 0–90 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position. ( ) Set the X1 MULTIPLIER pushbutton to the ON (in) position.
( ) Perform the three marked steps X1 below. ( ) The readings should be approximately 9 Hz to approximately 110 Hz.
X1 X10 X100 X1000 ( ) ( ) ( ) ( )1 Adjust the VARIABLE FREQUENCY control [R3/R4] to maximum counter-clockwise.
( ) ( ) ( ) ( )2 Adjust the VARIABLE FREQUENCY control slowly to maximum clockwise. ( ) ( ) ( ) ( )3 Adjust the LEVEL control to maximum counter-clockwise OFF position.
( ) Set the X10 MULTIPLIER pushbutton to the ON (in) position. ( ) Repeat the three marked steps X10 above.
( ) The readings should be approximately 90 Hz to approximately 1100 Hz. ( ) Set the X100 MULTIPLIER pushbutton to the ON (in) position.
( ) Repeat the three marked steps X100 above. ( ) The readings should be approximately 900 Hz to approximately 11 kHz.
( ) Set the X1000 MULTIPLIER pushbutton to the ON (in) position. ( ) Repeat the three marked steps X1000 above.
( ) The readings should be approximately 9 kHz to approximately 110 kHz. ( ) Disconnect the frequency counter from the generator.
( ) Set the X1000 MULTIPLIER pushbutton to the ON (in) position. ( ) Repeat the two marked steps 1 below for each pushbutton (0 –> 90) of the 0–90 selector switch bank.
0 10 20 30 40 50 60 70 80 90 Set the X pushbutton of the 0–90 selector switch bank to the ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )1 ON (in) position.
0 10 20 30 40 50 60 70 80 90 Observe the meter reading at each switch position, indication ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )1 should stay the same.
( ) Repeat the two marked steps 2 below for each pushbutton (0 –> 9) of the 0–9 selector switch bank. 0 1 2 3 4 5 6 7 8 9 Set the X pushbutton of the 0–9 selector switch bank to the ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )2 ON (in) position.
0 1 2 3 4 5 6 7 8 9 Observe the meter reading at each switch position, indication ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )2 should stay the same.
( ) Repeat the two marked steps 3 below for each pushbutton (0 –> .9) of the 0–0.9 selector switch bank. 0 .1 .2 .3 .4 .5 .6 .7 .8 .9 Set the X pushbutton of the 0–0.9 selector switch bank to the ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )3 ON (in) position.
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 Observe the meter reading at each switch position, indication ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )3 should stay the same.
( ) Adjust the LEVEL control to the maximum counter-clockwise OFF position. Attenuator Switches and External Load Switch Check
The accuracy of these measurements will be +/- .2 dB +/- the accuracy of the AC VTVM. ( ) Set the AC VTVM to measure from 10 to 70 dB.
( ) Connect the AC VTVM to the 10V OUT output jack of the generator. ( ) Set the X100 MULTIPLIER pushbutton to the ON (in) position.
( ) Set the 0 pushbutton of the 0–90 selector switch bank to the ON (in) position. ( ) Set the 0 pushbutton of the 0–9 selector switch bank to the ON (in) position.
( ) Set the 0 pushbutton of the 0–0.9 selector switch bank to the ON (in) position. ( ) Set all three ATTENUATOR pushbuttons to the OFF (out) position.
( ) Record the AC VTVM reading. __________ ( ) Set the X10 ATTENUATOR pushbutton to the ON (in) position. (The reading should be 10 dB below original meter indication)
( ) Set the X10 ATTENUATOR pushbutton to the OFF (out) position. ( ) Set the X20 ATTENUATOR pushbutton to the ON (in) position. (The reading should be 20 dB below original meter indication)
( ) Set both the X10 and X20 ATTENUATOR pushbuttons to the ON (in) position. (The reading should be 30 dB below original meter indication)
( ) Set both the X10 and X20 ATTENUATOR pushbuttons to the OFF (out) position. ( ) Set the X40 ATTENUATOR pushbutton to the ON (in) position. (The reading should be 40 dB below original meter reading)
( ) Set both the X10 and X40 ATTENUATOR pushbuttons to the ON (in) position. (The reading should be 50 dB below original meter indication)
( ) Set the X10 ATTENUATOR pushbutton to the OFF (out) position. ( ) Set both the X20 and X40 ATTENUATOR pushbuttons to the ON (in) position. (The reading should be 60 dB below original meter indication)
( ) Set all the X10, X20, and X40 ATTENUATOR pushbuttons to the ON (in) position. (The reading should be 70 dB below original meter indication)
( ) Set the AC VTVM on the 10-volt scale. ( ) Set all three ATTENUATOR pushbuttons to the OFF (out) position.
( ) Set the EXT LOAD pushbutton to the ON (in) position. (The AC VTVM reading should increase slightly.)
( ) Set the EXT LOAD pushbutton to the OFF (out) position. (The original AC VTVM indication should return.)
( ) Disconnect the AC VTVM. ( ) Connect a high impedance (12 k or higher) voltmeter [VTVM] to the SYNC output [rear of unit].
( ) The meter reading should be at least 1 volt rms. ♦ After the unit has been operated for at least 48 hours, readjust both the DIST ADJ [R109] and the METER ADJ [R132] controls for a 10-volt output.
( ) Disconnect all test leads and cables from the unit. ( ) Set the POWER switch to the OFF position.
( ) Disconnect the line cord from the AC power lines. ( ) Calibration procedure is complete. Kataloq: Electronics Electronics -> Design Guide Comparison between Electronics -> To the Members of the California State Senate Electronics -> Proof of designation Electronics -> Covered electronic waste recycling payment claim Electronics -> Covered electronic waste transfer receipt Electronics -> Source anonymous covered electronic waste (sa cew) collection log Yüklə 70.12 Kb. Dostları ilə paylaş:
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