Filter
Top Products
Introduction and Specifications
1–2
760A / 760D / 760N
The display is set for a “Sound Stage” orientation when the 760A is shipped
from the factory. This provides a display where monaural amplitudes are
oriented on the vertical axis of the CRT.
An alternate XY graticule is shipped as a standard accessory with the 760A.
This graticule can be installed if you are familiar with or desire the display
orientation provided by an XY monitor. Instructions for installing the XY
graticule are found in SECTION 3 INSTALLATION.
Automatic or manual gain control is front panel selectable. This feature allows
flexible control of the pattern size over a wide range of input signal amplitudes.
In the absence of an input signal, Z–Axis dimming prolongs CRT life.
Three 100–segment LED bars indicate the levels of the left stereo channel, right
stereo channel and a selectable third channel. The third bar can be set to display
the levels of (L+R)/2, (LR)/2, or the rear–panel AUXILIARY input. Both
(L+R)/2 and (LR)/2 are internally derived, and represent half the sum or
difference of the input voltages ([VLVR] / 2). In this way when the left and right
channels are balanced the sum will be displayed at that same level, while the
difference will be displayed at “0”.
The EXPAND SCALE control is a momentary contact front–panel push button,
which greatly improves the accuracy of level setups. Pressing this button
switches to the blue expanded scale which allows accurate setting of the signal
level for alignment, as specified by broadcast authorities. For the 760A the
alignment level is 8 dB. This level is labeled “TEST”, and is indicated by the
“arrow head” scale marks.
For the 760D the alignment level is –9 dB, indicated by the “arrow head” scale
marks. The 760N alignment level is marked “TEST”, and is at 0 dB. In all
cases, the normal scale lines up with the expanded scale at the alignment level.
The PEAK HOLD control is a latching front–panel push button. Indicated peaks
are displayed for approximately three seconds when this function is selected.
The 760A, 760D, and 760N conform to the dynamic response characteristics of:
760A: EBU–3205, IEC 268–10, and IEEE Proposed PPM specification.
760D: DIN 45 406
760N: Nordic Technical Recommendation N9.
Table 1–1 shows the peak bar indication when an isolated tone burst of a given
duration is applied. The response shown is relative to the indication for a
continuous tone of the same amplitude. The burst must contain at least 5 cycles,
which requires a frequency of at least 10 kHz for the shortest bursts.
Bar Graph
Dynamic response
characteristics for peak
program meters