Chapter 2_______________________________________Zaxcom Digital Wireless System User’s Manual
28
Recording modes:
•
STOP
– Recording is stopped (accompanied by 1 beep).
•
LREC
– Recording is started and Loop Record mode is enabled (accompanied by 2 beeps).
•
REC
– Recording is started and Non-Loop Record mode is enabled (accompanied by 2 beeps).
•
WAIT
– May appear just before going into record, or if the card is ejected while recording.
Audio Gain page
GAIN 20dB
Page purpose:
This page adjusts the mic gain, using the
INC
or
DEC
key.
Parameters:
[value range:
0
to
52
, step:
2
]
When audio is applied to the microphone input, the LCD indicates the signal strength using a bar graph displayed
horizontally from left to right (-40 to 0 dBFS).
The gain should be set so that the meter is peaking between
-
20 and
-
10 dBFS. This is about half way between
-
20 and 0 dBFS on the meter.
If no microphone is connected, the bar
graph remains blank.
The transmitter features a digitally controlled analog limiter that is situated before the A/D converter. This
prevents the A/D convertor from clipping by automatically attenuating the mic gain when excessive audio is
detected.
The limiter engages before the signal exceeds the digital capabilities of the signal path. The limiter activates at -6
dBFS. The gain level should be set low enough to prevent it from engaging, even when talent is screaming.
Audio Transmitter Frequency page
TXFREQ 581.6
Page purpose:
This page sets the audio transmitter’s center frequency.
Parameters:
[value range: (see
Table 1.3
), step: .
1
]
The transmitter can operate on any frequency between 518.0 and 870.0 MHz but your unit can only operate in its
assigned block within this frequency range.
There is a one-second delay while moving to a new frequency. If the frequency is changed quickly, the transmitter
remains quiet until the desired frequency has been selected.
When operating multiple transmitters in the same area, it is recommended that you use at least 1 MHz separation
between radios. If audio frequencies are difficult to obtain, the minimum spacing can be as low as 0.6 MHz while
using US modulation, or 0.5 MHz while using European modulation. Using a large frequency separation between
each transmitter aids in their clear reception. Maintaining a distance of 20 feet or more between transmitter and
receiver also aids in reception when several transmitters are used at the same time. This will prevent any
transmitter from de-sensing any of the receivers.
Frequency planning programs, which are used to prevent intermodulation problems, are not needed when using
the Zaxcom Digital Wireless system. However, if regular FM wireless mics are being used near the Zaxcom
system, you must plan your frequency assignments to prevent intermodulation. When two FM transmitters come
close to each other, they can produce interference on adjacent frequencies. Since this interference is transmitted
over the air, there is no way for a Zaxcom receiver to reject it. However, Zaxcom transmitters do not suffer
from this problem.
Transport Control page
STOP 00:00:00:00
000:
Page purpose:
This page allows the operator to review the recorded audio.
The top line, left-hand side displays the current mode:
REC
,
PLAY
or
STOP
. The right side contains the
timecode based on the current mode. The bottom line contains the count of recording segments on the currently
installed card.
