Step 1 - LO-End :-
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Set the '5K Lin' pot fully anti-clockwise
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Set [FREQUENCY], [WAVE SHAPE] and [CV A] to their minimum (CCW) position
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Set [CV B] to ‘0’
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Monitor [SAW-DC]
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Adjust P101 for an output of 16Hz
Step 2 - Wave Shaper :-
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Set P201 to its mid-position
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Monitor [SHAPED DC]
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Adjust P201 for best sine shape which should be similar to that in Figure B. Note that the wave shaping circuitry can take a couple of seconds to stabilise so make small adjustments and wait for the waveform to stabilise
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Turn [WAVE SHAPE] to maximum and check that the waveform is similar to that in Figure C
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Repeat steps (3) and (4) until both ends of [WAVE SHAPE] are a best match for those in Figures B & C
![](es20-sine.jpg)
Figure B
![](es20-saw.jpg)
Figure C
Step 3 - HF Trim:-
![](calibration.jpg)
Stage 1:
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Monitor [SAW DC]
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Set [CV-B] pot to '0'
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Set REFERENCE to 0.0V to [CV A]
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Adjust [FREQUENCY] for 300Hz using [CV-B] pot for fine tuning
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Set REFERENCE to 2.0V to [CV A]
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Adjust ‘5K Lin’ pot for 75Hz
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Repeat steps (3) to (5) for best accuracy
Stage 2:
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Set REFERENCE to 2.0V to [CV A]
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Set [CV-B] pot to '0'
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Adjust [FREQUENCY] for 300Hz using [CV-B] pot for fine tuning
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Set REFERENCE to 0.0V to [CV A]
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Adjust P102 for 1200Hz
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Repeat steps (1) to (5) for best accuracy
Calibration of the HF Trim is a series of successive approximations so stages 1 and 2 should be repeated several times for optimum accuracy.