Front Panel - Readout Section (Left Side); Phones; Bargraphs And Led Indicators, Select Buttons; Fm Modulating Metering - DEVA Broadcast DB4004 Maintenance And Operation Instruction Manual

FRONT PANEL – READOUT SECTION (LEFT SIDE)

Phones

Phones jack to monitor the received signal. Headphones volume can be menu adjusted by going
to Settings > Audio / MPX Outputs > Phones Volume.

Bargraphs and LED Indicators, Select Buttons

FM MODULATING METERING

– 60 segments LED bargraph indicator to visualize the highest Positive or Negative deviation
or both of them (default) as selected by the SELECT button. It is peak-responding, and it updates-
and-holds the highest peak. When both the POS DEV and NEG DEV indicators are lighted, the
highest deviation in either polarity is shown and this is the default display mode. SELECT button
also switches the bargraph to display the injection level of 19 kHz stereo pilot signal, which is
usually set to 7-8 kHz injection. Stereo PILOT signal is read on the lower metering scale. It is
calibrated in appropriately smaller scale then the carrier deviation.

SELECT Button

– used to change mode of the LED bargraph indicators and associated LED indicators. Possible
selections are POS DEV, NEG DEV, POS DEV + NEG DEV, PILOT.

AUDIO DEMOD METERING

– two 60 segments LED bargraphs showing Left and Right or L+R and L-R demodulated audio.
By default the AUDIO DEMOD METERING displays left- and right channels of the stereo pair
with the L / R indicator lighted. It is recommendable leaving this display in the default mode. The
SELECT button can be used to switch the AUDIO DEMOD METERING display between L / R and
L+R / L-R. Upon selecting any of the L / R or L+R / L-R the relevant indicator will light, but the
headphones will continue monitoring the L / R stereo program.
Although there are instances where the L+R and L-R bargraphs may be close in value, as a rule
of thumb, the L-R meter should generally lag the L+R meter by at least a few dB, i.e. the L+R sum
will always have more energy than the L-R difference and this applies to nearly all recorded music.
For signals where voice announcements are predominant, without background music or for other
mono sources the L-R indication may drop almost off-scale.
The SELECT button associated with the above described bargraphs, cycles amongst various
options, each of them identified with an associated LED indicator.
65 Aleksandar Stamboliyski Str., 8000 Bourgas, Bulgaria
Tel: +359 56 820027, Fax: +359 56 836700
E-mail: office@devabroadcast.com ,Web: www.devabroadcast.com
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