User manual

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The Stage Announce output is balanced and provides an average signal level of about -5dBu. See Figure 6. The program
inputs accept balanced lines with a signal level of +4 to +8dBu. See Figure 6.
Connection To Existing Microphones, TW Type User Stations and Other Sources
Any series 4000 Control Station can be connected to existing microphones (Figure 7 and Figure 8) and TW type user stations.
A series 4000 Control Station can use the microphone in an existing TW type user station. Connect the Unswitched Mic output
(USM) from the TW user station to the line level input on the Control Station. See Figure 9. For connection to a Model 801
Master Station, see the service manual.
Options Installation
The design of the Series 4000 IFB system permits easy field installation and adjustment of the options and features discussed
below. Options/features include priority control, speaker muting zones or areas, return IFB, expansion of the IFB ALL
function and selection of monaural IFB (same signal the interrupted program in both ears). The return IFB option requires
additional equipment to be supplied by the customer or to be custom-ordered from RTS Systems. The additional equipment
would normally consist of relays to switch line-level microphone signals in a suitable junction box and a power supply for the
relays. The relays are controlled from the Model 4010 Central Electronics unit. In addition, a modification to the Model 4020
for TW system type user station is required.
Setting Up Priority
The Model 4010 IFB Central Electronics, as supplied, has a priority arrangement by which one Control Stations will override
another. The priority of a Control Stations is determined at the Control Station. By changing which plug (Figure 10) goes to
which jack on the Control Station’s switchboard, the priority of that Control Station can be changed. See Figure 11 through
Figure 13. If desired, the priority may be defeated by removing U6 and U16 in the Model 4010 Central Electronics. In this
mode all Control Stations have equal priority. The priority override function works only with the IFB keys. The stage
announce has no priority feature. The signals are merely mixed together should two (2) Control STations be keyed
simultaneously.
Setting Up Speaker Muting Zones
Two (2) sets of relay contacts are provided at the back panel of the 4010 Central Electronics for area control of speaker
muting. These relays work in conjunction with the Stage Announce (SA) buttons on the Control Stations. This permits, for
example, the audio operator to use the SA without interrupting the director’s program monitor speaker and vice versa. By
cutting out the resistors, shown in Figure 14, the relay will be deactivated for that station. The station numbers are determined
by their priority selection priority 1, station 2 has priority 2, etc. Normally, with all resistors intact, both relays work when an
SA button is pressed on any Control Station.
Return IFB Installation
A return-send function may be incorporated with some small modifications (see Figure 15). This feature allows the talent at
the User Station to communicate with the Control Stations via a closed-circuit loop. This is done at the User Station by
switching in an extra load, usually a lamp, across the feed to that station. A sensor circuit in the Central Electronics turns on a
transistor whose collector terminal appears open ended at a 9-pin miniature D connector on the rear panel. This allows a relay
to be used to transfer the announcer’s microphone from the program line to a monitor amplifier in the control room. The
person at the Control Station may now listen to the announcer without the signal going over the air. The output through the
miniature D connector is capable of operating a 12- to 24-volt relay at up to 50 milliAmps. The relay will trigger when 60
milliamps to 200 milliamps is drawn from the line. The exact value is set by R4 for channel 1, R33 for channel 2, R62 for
channel 3, and R91 for channel 4. See Figure 15. To trigger the relay, switch a 12-volt 90 milliAmps lamp across the 12 Volts
in the user station.
NOTE: Only one (1) user station per output may be used when the return option is used.