Voice Card Troubleshooting Guide

The MEMORYMOOG has a software routine to isolate defective VOICE CARD OSCILLATORS. Depress the AUTOTUNE button and observe the display. In 5 to 10 seconds, the display will show "X tuned", where X is the number of usable voices. X will equal 6 if all VOICE CARDS are good. If X is less than 6, faulty VOICES can be isolated as follows:

1. Depress "C7" followed by "ENTER" twice.

2. The display will show "VOICE 7".

3. Depress any VOICE number (1 through 6) desired To be tested, where VOICE A » 1, VOICE B ■ 2, etc.

4. After about 1 second the display will show "OSC ?".

5. Depress any oscillator number (1 through 3) desired to be tested.

6. One of the following will be shown on the display in a flashing format:

"DEAD OSC", which is self-explanatory, or the letters "XX", "YY" or "22". "XX", "YY", "ZZ'are 2-digit hexidecimal numbers indicating the AUTOTUNE voltages for the OSCILLATOR. Nominal values of 7F hex would indicate all three oscillators are close in value to each other but a 00 or FF display for one or more of the three numbers indicates the oscillator(s) cannot be AUTOTUNED and must be recalibrated.

7. Depress ENTER twice to continue testing as in Step A2 for other VOICES and/or OSCILLATORS. Entering an invalid number for a VOICE >6 or OSCILLATOR >3 will exit this testing mode.

INDIVIDUAL VOICE CARD TROUBLESHOOTING SYMPTOM CAUSE/REMEDY

1. One of the three Check for 10 volt waveforms

OSCILLATORS is dead, or (PULSE, SAWTOOTH, TRIANGLE) waveforms are missing. at:

Osc. 1 ,U3 (4016) Pins 1,4 & 8 Osc. 2,U7 (4016) Pins 1,4 i 8 Osc. 3,010(4016) Pins 1,4 & 8

Was this article helpful?

0 0

Post a comment