Wheatstone TV-80, Technical Manual

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A P P E N D I C E S
TV80 / Sep 98
For your convenience, here are some commonly encountered level
measurement values:
0 dBm in 600 ohms = .775 V = 0 dBu in any impedance
+4 dBu = 1.23 V
+8 dBu = 1.95 V
-10 dBu = .245 V
-20 dBu = 77.4 mV
-50 dBu = 2.45 mV
When checking out a system, remember to measure the input
voltage at the connector, as variations in input impedance and genera-
tor source impedance can invalidate your results.
Extender Ribbons
TV-80 consoles are shipped with EXTENDER RIBBONS. These
3-foot cables allow individual modules to be removed from the console
mainframe and still remain powered-up and connected to the bus
system, for active troubleshooting. There are three types of extender
ribbons: one for main modules, one for fader panels, and one for
overbridge preselector panels.
Troubleshooting
Basic Procedures
If you have encountered difficulty in testing your installation, check
the items listed below before opening the console. Note that some items
may seem very obvious; it is often the most obvious things that we
overlook.
1) Are the console power supply systems properly installed and
operating correctly?
2) Are the sources you are using to test the console installation
producing normal, line level signals? For example, if a cart machine is
the source, is the cart playing? Is the output of it connected to the
console?
3) When checking for sound from the control room speakers, is the
external monitor amplifier on? Is the amplifier volume turned up to a
normal level? Are the speakers connected to the amplifier outputs? Are
the console’s SOLO and CUE functions deactivated? (Under normal
programming they will interrupt the regular monitor signal.)
4) If you have checked external devices and connections, and feel
that the problem is within the console, double check all wiring before
attempting to troubleshoot the console itself.
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