Glensound GSOC24, Схема подключения

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G
GLENSOUND ELECTRONICS LTD
Apr 20th 2000
File AP24 - 51
Issue 1
TECHNICAL NOTES
Intelligent Gain Software in GSOC24 Commentators Boxes
GENERAL
The Glensound coaxial commentators equipment has limited dynamic range through the coaxial cable. It is
therefore advantageous to control the GSOC24 commentators box front end gain to optimise the signal to noise
ratio. Each channel input is therefore fitted with microcontroller controlled input amplier along with a limiter
circuit. The microcontroller makes decisions on the correct gain setting by observing how often and how hard
the limiter is asked to work as well as observing the input levels against a number of threshold levels. This
circuit does not respond rapidly but is designed to optimise the gains over a long time period. Operating the
phantom power switch always resets the system and sets the initial gain at a lower level for phantom powered
mics.
SOFTWARE VERSION 1.2
This version of software increases the speed of response and gives the customer options depending on links
available on the PCB.
Normal use is with no links made.
If the Pin 6 link is made then the unit will never increase its gain above the starting point, but will reduce the
gain if the level is perceived to be too high. This setting may be useful for noisy events.
If the Pin 4 link is made then the unit will never decrease its gain from the starting point, but will increase it if
the level is perceived to be too low. This may be useful for quiet events.
If both links are made the gain is fixed.
This fixed gain is nominally 57 dB for normal mics and 44 dB if the phantom power switch is on.
TO CHANGE LINKS
See drawing number A4-13849. This shows the location of each link on the PCB GSN37.
This PCB is located immediately behind the front panel XLRs.
The procedure is as follows:-
Remove front panel ( 4x Screws )
Withdraw the front panel assembly, then the bottom of GSN37 can be clearly accessed.
To make the links it is only necessary to dab them with a little solder and a hot soldering iron.
Replace the front panel.
FACTORY SET UP
Glensound always despatch the commentators boxes in the fully automatic mode. That is with no links made.