User manual TL AUDIO VTC

[. . . ] OPERATION SECTION ­ CONTENTS 1. 1. 1 1. 2 1. 3 1. 4 1. 5 Introduction. Input Channel Overview. Precautions. Page Number 2 3 4 5 5 6 7 7 8 8 9 9 9 ­ 10 10 10 10 11 11 11 11 12 12 12 12 ­ 13 13 13 13 2. 2. 1 2. 2 2. 3 2. 4 2. 5 2. 6 2. 7 2. 8 2. 9 2. 10 2. 11 2. 12 2. 13 2. 14 2. 15 2. 16 2. 17 2. 18 2. 19 2. 20 Installation. AC Mains Supply. Meter Bridge Connection. 3. 3. 1 3. 2 3. 3 3. 4 3. 5 3. 6 3. 7 Channel Module. Input Stage. Main Channel Output Stage. 14 14 ­ 15 15 15 ­ 16 16 ­ 17 18 ­ 19 20 ­ 22 23 ­ 25 26 27 27 ­ 28 28 28 28 ­ 29 29 30 ­ 31 31 ­ 32 32 ­ 33 33 4. 4. 1 4. 2 4. 3 4. 4 4. 5 4. 6 4. 7 4. 8 4. 9 4. 10 Master Section. Auxiliary Master Sends. [. . . ] There are two choices: · ON Post Fade group signal for odd numbered groups (1, 3, 5, 7) is fed to main mix left. Post Fade group signal for even numbered groups (2, 4, 6, 8) is fed to main mix right. · ON + L/R Post Fade group signal to main mix left and right outputs equally. 4. 10 MASTER LEFT + RIGHT OUTPUTS Balanced XLR sockets for the master left and right outputs are found on the rear connector panel at a nominal level of +4dBu, and there are also unbalanced 1/4 inch jack outputs at a nominal level of 10dBu. Insert points are post the valve stage and pre fader, connected via stereo 1/4 inch jacks on the rear connector panel. Output level is shown on the Left and Right VU meters on the meter bridge above the Master Section. VALVE STAGE The L + R mix amplifiers use a combination of low noise balanced IC first stage followed by an ECC83/12AX7A valve stage. FADER The 100mm fader for the Left/Right output controls the main stereo mix level. STATUS Automation is an optional extra and when fitted `Status' acts as a momentary switch intended to identify the presence of a signal path to the automation system computer - in effect, a local status switch. AUTO If automation is fitted, the Auto button allows a channel's automation stage to be bypassed if required, thus removing any unwanted VCA stages from the signal path. Internal links are fitted such that this switch has no effect on a non-automated console. If automation is fitted then the links should be removed (see Technical Section 3. 8) TECHNICAL SECTION Contents. SPECIFICATIONS Input Impedance (electronically balanced) Mic input: All other inputs: Output Impedance All balanced outputs: All unbalanced outputs: Maximum output levels Direct, Group, L/R (balanced): L/R (unbalanced): Insert sends: Maximum Gain Mic input to direct output: Line input to direct output: Frequency Response Mic input @40dB gain to direct output: Mix Noise Main L/R output (reference to +4dBu nominal): Master fader down: Master fader @ 0dB: With 32 channels routed, faders at 0dB, channels open: Group Noise (reference to +4dBu nominal) Fader down: Fader @ 0dB, no channels routed: with 32 channels routed, faders @ 0dB, channels open: Input Noise Mic Input Equivalent (EIN): (22Hz to 22kHz, 150 ohm termination, 60dB gain) THD+Noise (From 10Hz to 40kHz @ 0dBu) Direct output: Groups: L/R: Crosstalk Line input to adjacent channel: 2. 5 kohms 10kohms minimum 100 ohms 47 ohms +26dBu +20dBu +20dBu +70dB +32dB 20Hz to 20kHz +0, -1dB -97dBr -89dBr -75dBr -94dBr -92dBr -75dBr -127dBu 0. 02% 0. 03% 0. 03% -100dB @ 1kHz, -83dB @ 15kHz Due to a policy of continuous development, the above specifications are subject to change without notice. 4. 1 4. 2 4. 3 4. 4 4. 5 4. 6 4. 7 4. 8 4. 9 4. 10 4. 11 4. 12 4. 13 4. 14 4. 15 4. 16 4. 17 5. Signal Flow Diagrams. 39 39 40 40 40 40 ­ 41 41 41 41 ­ 42 42 42 ­ 43 43 43 43 ­ 44 44 44 ­ 45 45 46 46 ­ 47 47 47 47 48 48 ­ 49 49 49 49 ­ 50 50 ­ 51 51 51 52 53 1. The VTC console mechanical construction consists of a number of "bays", each of which houses 8 input channels, plus a further bay for the Master Section. Each bay operates as a sub-system with its own grounding, PSU Regulators, and balanced audio signal connection between bays. The external PSU provides rectified but unregulated DC which is connected via a heavy duty multicore cable to the console. Inside the console frame, the raw DC is bussed to every bay where it is separately fused and regulated. Power Supply Fault Finding. 35 CAUTION: THE POWER SUPPLY AND CONSOLE CONTAIN HIGH VOLTAGES (UP TO 250V DC) AND HIGH POWER CAPACITY, WITH A RISK OF PERSONAL INJURY AND FIRE. SERVICE SHOULD BE PERFORMED BY COMPETENT QUALIFIED PERSONNEL, IN ACCORDANCE WITH CORRECT ENGINEERING PRACTICE. IF IN ANY DOUBT, REFER SERVICE TO THE RETAILER OR DISTRIBUTOR OF THE CONSOLE. The external power supply contains a transformer with a number of secondary windings. The fuse ratings and the power supply rails to which they refer are marked on the chassis adjacent to each fuse. [. . . ] Talkback and Control Room dim are controlled by the signal "T/B ON" at CN18 pin 12. This signal is either momentary if jumper J2 is fitted (the default setting), or latching if J1 is fitted. "T/B ON" is also taken from PC351 on a flying wire loomed with the talkback microphone cable to PC348 on the upper Master Module. If talkback does not appear on the outputs but the switch illuminates, check that the talkback destination is selected on the upper Master Module and the output fader is open, and that the flying cable is connected to PC348. [. . . ]