10
3
APPENDIX A
OPTIONAL FOOTBALL MODIFICATIONS
GENERAL DESCRIPTION
In Audiocom
®
Intercom Systems, the Mic-Kill feature is used to turn off any activated
microphones on a selected channel. The Mic-Kill feature is activated when the beltpack
receives a 24 kHz signal from the channel. In some applications the Mic-Kill and Call
signal features are not desired and need to be disabled.
ELIMINATING MIC-KILL AND CALL SIGNAL
CAUTION
: TO PREVENT DAMAGE TO THE EQUIPMENT, THESE MODIFICATIONS
SHOULD ONLY BE MADE BY QUALIFIED TECHNICIANS.
If desired, the Mic-Kill and Call signal features can be disabled in the NFL-2002 by
removing a surface-mounted capacitor from the printed circuit board. Perform the
following:
1. Before making changes to the printed circuit board, disconnect all power and line
connections from the beltpack.
2. Refer to Figure 3 and locate C61 on the underside of the printed circuit board.
3. Remove capacitor C61 from the printed circuit board.
RESTORING MIC-KILL AND CALL SIGNAL
To restore the Mic-Kill and Call signal features, replace C61 with Telex
®
part number
102881-140, 1500 pF, 50V capacitor.
Introduction
The Audiocom
®1
NFL-2002 is a microprocessor controlled two-channel
intercom beltpack. An internal switch and jumper setting allows the unit to be
used with Clear-Com
®2
components, if desired. Other internal switch and
jumper settings allow the unit to be uniquely configured to the operator’s
requirements.
OPERATION
SYSTEM POWER
The NFL-2002 beltpack receives power externally in one of two ways:
• The intercom channel
• The local-power (pin 2) of the intercom channel connector
INITIAL NFL-2002 SETUP
The channel termination is initially set for balanced operation, which is
compatible with other Audiocom
®
equipment. If the unit is going to be
connected to Clear-Com equipment, one switch must be changed as
described on page 11.
The headset is auto-sensing which means the unit automatically determines if
an Electret or Dynamic headset is attached to the unit.
1. Audiocom
®
is a registered trademark of Telex Communications, Incl., Burnsvilled, MN 55337
2. Clear-Com
®
is a registered trademark of Clear-Com Intercom Systems.
