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Data Sheet, Inatallation Instructions and Schematic - PDF Pages
The RSA-U5 is used to connect voice logging recorders to two-way
radios that do not have an output for recorders, such as a mobile
radio that is used as a base station. Radios with wired connections
for remote control (tone, DC, or local) can usually be directly
connected to most recorders and do not require the RSA-U5.
Since connections must
be made inside of the radio, it should only be installed by a radio
service technician that is qualified to service the radio.
► Adjustable gain amplifiers allow you to independently match
transmit and receive audio levels for optimum recordings.
► Switch selectable mixing of receive and transmit audio at all
times or transmit audio that is only present with active PTT.
► Optically isolated DC sensing mutes the transmitter microphone
audio when the radio is not transmitting (push-to-talk is not
► Includes 110vAC power supply, eighteen inch input cables for radio
connections and an RJ-11 modular audio output jack.
► Red LED to indicate PTT (Push To Talk) activity.
Green Power LED.
► If the receive audio source is the radio speaker, the recorded
audio will increase and decrease with the volume control on the
radio. To prevent this, it is recommended that the receive audio be
sourced from the radios squelched discriminator audio so that the
position of the volume control on the radio will not have any
control over the recorded audio.
► If your connection to the radioís transmit audio is at a point
where microphone audio is only present when transmitting, you can
place the Transmit Audio Switch in the RX+TX position and leave the
two wire TX-SENSING cable disconnected. In this mode, the RSA-U5
will mix transmit audio with receive audio at all times.
► If your connection to transmit audio is at a point where
microphone audio is present when the radio is not transmitting and
the Transmit Audio Switch is in the RX+TX position, you will record
room audio when not transmitting. In this case, the mute control
cable should be connected to a place in the radio that provides
between 5vDC and 16vDC when transmitting and the switch placed in
the TX-PTT position. This connection powers an optically isolated
sensing circuit so that the output will only have microphone audio
when the radio is transmitting (PTT is active).
► The RSA-U5 has two screwdriver adjustable audio output
adjustments. One adjusts the volume of the receive audio that is fed
to its output jack, the other adjusts the volume of transmit audio
fed to the output. Adjust these controls as needed to match levels
and for the best recorded audio. Adjust clockwise to decrease,
counter-clockwise to increase. Do not force these controls.
► The modular phone jack (RJ-11) on the RSA-U5 provides line level
RX+TX audio for your recorder (suitable cables are supplied with
Omnicron recorders). Only the center two wires in this jack are
used. WARNING: Connecting this jack to an active phone line could
damage the adapter and will void its warranty.
The RSA-U5 is
supplied with cables and connectors wired to meet most standard
applications. It can also be customized to meet unusual
requirements. Since connections to most radios must be made inside
of the radio, only a radio technician familiar with the radio should
perform the installation.
1. The short 3 wire gray cable connects to the
2-way radio audio.
Connect the BLACK lead to radio common (chassis ground).
Connect the GREEN lead to receive audio (0.1 to 1.5 vAC).
Connect the RED lead to transmit audio (0.05 to 1vAC).
2. The short two wire gray cable connects to
two-way radio transmitter power (DC). If microphone audio is only
active when transmitting, this cable does not need to be connected.
Place the Transmit Audio Switch in the RX+TX position.
With the Transmit
Audio Switch in the TX-PTT position, these wires feed an optically
isolated sensing circuit that will mute the transmit audio whenever
they do not have between 5vDC (1 ma) and 16vDC (4 ma) present across
them. Connect the BLACK lead to negative (-) side and the RED lead
to positive (+) side of switched transmitter power. This voltage
also powers a green LED.
3. The RJ-11 telephone style jack on the
RSA-U5 is used to connect the audio output from the RSA-U5 to your
recorderís audio input. Receive and transmit audio are mixed on the
center two pins of this RJ-11 jack. Use the cable supplied with your
recorder or other suitable wiring to connect from this jack to your
4. Plug the supplied AC adapter into the Power
(5 to12vDC) jack and AC power. A red LED on the RSA-U5 lights when
power is ON.
5. Check that the recorder is recording both
transmit and receive audio properly. If needed, increase or decrease
audio levels using the small screwdriver adjustable controls on the
RSA-U5. One adjusts the level of receive audio, the other adjusts
transmit audio level (turn clockwise to decrease, counterclockwise
The RSA-M4 is supplied with cables and connectors wired to meet most standard applications. It can also be
customized to meet unusual
IN CASE OF DIFFICULTY
If the unit fails to work properly, check all connections, audio,
and DC voltage levels. Test your recorder to see that it is
operating properly. Assistance is available from your place of
purchase, or directly from Omnicron Electronics.
Receive Audio: >1M ohm DC,
>10K ohm AC, 0.1 to 1.5 vAC
Transmit Audio: >1M ohm DC,
>10K ohm AC, 0.02 to 1 vAC
Audio Output: RX >10db gain,
TX >30db Gain, 600 ohm, RJ-11
Transmitter activity sensing:
Between 5 and 16vDC, 1 to 4 ma
Power: 5 to 12vDc, 10 ma,
2.1mm x 5.5mm, AC power adapter
Size & Weight: 3" x 2" x 1"
(without cables), 3oz (without PSU)
Warranty: Limited, twelve
law 90-351 title 18, section 2511, sub section 2D,
requires that at
least one participant in a recorded
conversation be informed of the
recording. Check your
state and local regulations for further
assistance in he selection of the products
that are best suited to your application.