Manual

Model 370A User Guide Issue 2, August 2019
Studio Technologies, Inc. Page 15
MODEL 370A
INTERCOM BELTPACK
the talk function. When released the talk
function will turn off. Momentarily pressing
(“tapping”) the button will cause the func-
tion to change states; off-to-on or on-to-off.
Whenever the talk function is active the
green LED will light. The button will not be
lit when the function is not active.
Disabled
A button that is configured to the Disabled
mode will never allow talk audio to be sent
to the associated Dante audio output chan-
nel. But to provide “feedback” that the but-
ton has been pressed the button’s green
LED will flash rapidly three times. This says,
in effect, “Yes, I recognize that you pressed
the button but I’m not going to do anything
in response!”
Sidetone Function
The Model 370A includes a sidetone func-
tion that sends microphone audio to the
headphone output channels whenever
one or both of the talk buttons are active.
The quality of the sidetone audio should
be excellent and will provide Model 370A
users with a confidence signal that they
are actively talking to other intercom us-
ers. Sidetone audio will always be sent to
both the left and right headphone channels
and is not a configurable choice. This is
because the function is trying to simulate
what a user would hear if they didn’t have
a headset covering their ears. It is not in-
tended to indicate to the user which Dante
audio output (transmitter) channel or chan-
nels are actively sending audio.
The exact sidetone level is configured
from among five values within the STcon-
troller application. There is also a selection
choice for turning off sidetone. There is no
means of adjusting the sidetone level using
a physical button or control on the Model
370A unit. Also, the two headphone level
controls on the top panel of the unit do not
impact the sidetone level.
In most cases the exact sidetone level
setting is not critical and typical users will
not be concerned about revising it. But
setting the sidetone level to something
reasonable is important. Setting the level
too low will encourage users to speak too
loudly; setting it too high and users will
be tempted to speak hesitantly. And while
users aren’t provided with a sidetone level
control or other adjustment means, should
the need arise STcontroller allows rapid
adjustment of the sidetone level. In most
cases the default sidetone level, Medium,
should provide an appropriate level.
Call Function
An integrated call function allows Model
370A users, and users of compatible
equipment, to signal to each other visu-
ally. Individual call functions are provided
for each of the two talk channels. Either
or both can have its call function active at
any one time. Technically, call is achieved
by sending a 20 kHz audio tone on the
desired audio output channel. This signal
is summed (mixed) with normal talk audio.
The Model 370A’s two audio input chan-
nels continually monitor for the presence
of 20 kHz. A call signal is recognized when
a continuous 20 kHz tone is detected on
the audio input for that channel.
Normal talk audio signals will not be con-
fused with a call signal. Digital filters within
the Model 370A’s processor integrated
circuit limits the microphone input’s high
frequency response to about 10 kHz. This
helps to ensure that false call detection
won’t take place. Digital filtering is also
performed on the audio input (Dante re-
ceiver) signals before they are sent to the