Troubleshooting - Yamaha VL70-m Owner's Manual

2. Add all the converted numbers.
3. Divide the total by 128 and note the remain-
der.
4. Subtract the remainder from 128. The result
is the checksum.
5. Convert the decimal checksum back to
hexadecimal format using the above chart.
HEX DEC HEX DEC
40 64 50 80
41 65 51 81
42 66 52 82
43 67 53 83
44 68 54 84
45 69 55 85
46 70 56 86
47 71 57 87
48 72 58 88
49 73 59 89
4A 74 5A 90
4B 75 5B 91
4C 76 5C 92
4D 77 5D 93
4E 78 5E 94
4F 79 5F 95
HEX DEC HEX DEC
60 96 70 112
61 97 71 113
62 98 72 114
63 99 73 115
64 100 74 116
65 101 75 117
66 102 76 118
67 103 77 119
68 104 78 120
69 105 79 121
6A 106 7A 122
6B 107 7B 123
6C 108 7C 124
6D 109 7D 125
6E 110 7E 126
6F 111 7F 127

Troubleshooting

The VL70-m is a very versatile tone generator
with many features and functions that affect
operation. In many cases, what appears to be a
fault with the VL70-m can actually be traced to an
improperly set parameter or something as simple as
a bad connection.
Here's how to determine if the problem is internal
(e.g. parameter settings) or external (e.g. connec-
tions, amplifier, etc.):
Listen via headphones. Plug a pair of head-
phones into the VL70-m and play. If the
headphone sound is OK, then the problem is
most likely in the amplifier or mixer you are
using, or the audio connection cables.
Try adjusting all operational controllers —
modulation wheels, foot controllers, etc. In
some cases extreme controller settings can
cause unexpected sound or pitch ... or even no
sound at all.
Try selecting different voices. If the problem
occurs only on one voice then the voice param-
eters are most likely at fault. If the problem
occurs on all voices then a utility parameter
should be suspected.
The following are some common problems and
probable causes:
Symptom
• No power.
Possible Causes
• Is the AC adaptor properly connected to both
the VL70-m and an AC wall outlet (page 15)?
• If the AC apaptor is connected to a switched
AC outlet on another piece of equipment (an
amplifier, for example) is that devide switched
on?
107
Appendix