Sequential prophet 5 - R304 Wheel-Mod Noise Vca 8 Alance; R305 Wheel-Mod Lfo Vca Balance; R306 Lfo Triangle Symmetry

4-S R304 WHEEL-MOD NOISE VCA BALANCE
R304 (see SD312) is best trimmed by ear.
Start in BASIC TRIM SETUP, TABLE 4-0.
1. Turn R212, W-MOD SRC MIX. to 10<NOISE).
2. Switch on S216. W-MOD FREQ A DESTINATION.
3. Turn R203, OSC A FREQ, to 10.
4. Key CO and advance R702, MOD wheel, with same hand.
5. Trim R304 so OSC A pitch does not change as you advance R702. You can still hear the base pitch
even with the noise modulation.
4-6 R305 WHEEL-MOD LFO VCA BALANCE
R305 (see SD312) is similar to R304 (para. 4-5).
Start in BASIC TRIM SETUP. TABLE 4-0. By ear:
1. Switch on S216, W-MOD FREQ A DESTINATION.
2. Turn R203. OSC A FREQ, to 10.
3. Key CO and advance R702, MOD wheel, with same hand.
4. Trim R305 so OSC A pitch does not change as you advance R702.
With instruments, VCAs are trimmed so that with maximum CV applied there will be no output
(0.000V) when there is no input. Perform steps 1-3, above, then:
4. With DVM. probe U373-15.
5. Trim R305 so U373-15 reads 0.000V.
4-7 R306 LFO TRIANCLE SYMMETRY
R306 (see SD312) may be trimmed by ear, but instruments are preferred.
Start in BASIC TRIM SETUP. TABLE 4-0. By ear:
1. Turn R203, OSC A FREQ, to 10.
2. Switch on S209, LFO triangle.
3. Set R208, LFO FREQ, to about 5.
4. Key CO and advance R702, MOO wheel, with the same hand. Usten for smooth rise and fall of
OSC A pitch (frequency modulation).
5. If required, trim R306 to remove "glitch" in modulation.
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With instruments:
1. Turn R208, LFO FREQ, to 10.
2. With scope, probe U372-14. Note that U372 is mounted upside down.
3. The triangle waveform should look balanced, like Waveform 4-OA. Non-symmetry looks like
Waveform 4-OB. Trim R306 (see PA310U) if required to balance.
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