Zaxcom TRX900AA User manual

1
Table of Contents
KNOWING YOUR TRX-900AA .............................................................................................................................3
MAIN MENU............................................................................................................................................................. 6
Navigating the Main Menu ..................................................................................................................................................................................................6
Exiting the Main Menu ..........................................................................................................................................................................................................6
Audio Gain..................................................................................................................................................................................................................................6
UHF Transmit Frequency ......................................................................................................................................................................................................6
Transport Control.....................................................................................................................................................................................................................6
Timecode Frame Rate ............................................................................................................................................................................................................7
IFB Earpiece Select..................................................................................................................................................................................................................7
Time Left.....................................................................................................................................................................................................................................7
Lock Page....................................................................................................................................................................................................................................7
EXTENDED MENU.................................................................................................................................................. 8
Navigating the Extended Menu ..........................................................................................................................................................................................8
Exiting the Extended Menu ..................................................................................................................................................................................................8
High Pass Filter Adjust............................................................................................................................................................................................................8
Limiter..........................................................................................................................................................................................................................................8
1K Notch Filter .........................................................................................................................................................................................................................8
2K Notch Filter .........................................................................................................................................................................................................................9
UHF Signal Format..................................................................................................................................................................................................................9
UHF Transmitter Power Level..............................................................................................................................................................................................9
IFB Receive Mode .................................................................................................................................................................................................................10
IFB Voting Enable..................................................................................................................................................................................................................10
IFB Receive to Transmit time............................................................................................................................................................................................11
ZaxNet IFB Receive Frequency.........................................................................................................................................................................................11
ZaxNet IFB Transmit Frequency......................................................................................................................................................................................12
IFB Dropout Compensator.................................................................................................................................................................................................12
IFB Receive Pulse...................................................................................................................................................................................................................12
Power-Up Mode ....................................................................................................................................................................................................................13
Format Recording Card.......................................................................................................................................................................................................13
Time Code Jam Mode .........................................................................................................................................................................................................14
Time Code Source ................................................................................................................................................................................................................14
Time Code Output................................................................................................................................................................................................................14
Group ID..................................................................................................................................................................................................................................15
Unit ID......................................................................................................................................................................................................................................15
Dynamics .................................................................................................................................................................................................................................16
Analog to Digital Converter................................................................................................................................................................................................17
Battery Type ...........................................................................................................................................................................................................................17
Recording Mode ....................................................................................................................................................................................................................17
Boot Up Mode .......................................................................................................................................................................................................................18
Mute Switch............................................................................................................................................................................................................................18
Left Right Switch....................................................................................................................................................................................................................18
Side Tone Gain ......................................................................................................................................................................................................................18
IFB Remote Control ..............................................................................................................................................................................................................19
IFB Jam Threshold.................................................................................................................................................................................................................19
QRX Program.........................................................................................................................................................................................................................19
Home Screen Record / Stop..............................................................................................................................................................................................19
Phase Invert Channel...........................................................................................................................................................................................................20
TX Disable ..............................................................................................................................................................................................................................20
Low Battery Stop...................................................................................................................................................................................................................20
Record On Bootup ................................................................................................................................................................................................................21
Name........................................................................................................................................................................................................................................21
Encryption Menu...................................................................................................................................................................................................................21
Encryption Code page .........................................................................................................................................................................................................22

2
ACCESSORIES ....................................................................................................................................................... 23
STA ADAPTER .....................................................................................................................................................................................................23
STA OPERATIONS...............................................................................................................................................................................................24
Attaching the STA to the TRX-900AA...........................................................................................................................................................................24
Adjusting the Input Level ....................................................................................................................................................................................................24
Powering the TRX-900AA via the STA ..........................................................................................................................................................................24
Audio/Timecode Output Connection...............................................................................................................................................................................24
Timecode Input......................................................................................................................................................................................................................24
Operation of the STA...........................................................................................................................................................................................................24
MSA-100 MUTE SWITCH...................................................................................................................................................................................26
EA-100 EARPIECE ADAPTER ..............................................................................................................................................................................27
MEDIA ..................................................................................................................................................................... 28
Media Capacity......................................................................................................................................................................................................................28
Recording Format..................................................................................................................................................................................................................28
FIRMWARE............................................................................................................................................................. 29
UPDATING TRX FIRMWARE ..............................................................................................................................................................................29
UPDATING AN ERX WITH YOUR TRX-900....................................................................................................................................................30
INPUTTING AUDIO ............................................................................................................................................. 31
WIRING DIAGRAMS............................................................................................................................................. 31
Two Wire Microphone Configuration.............................................................................................................................................................................31
Three Wire Microphone Configuration..........................................................................................................................................................................31
Balanced Line Level and Timecode Input .....................................................................................................................................................................31
Line Level into STA Adaptor ..............................................................................................................................................................................................32
Audio / Timecode out of STA Adaptor...........................................................................................................................................................................32
Timecode Into STA / TCA-100 .........................................................................................................................................................................................32
ANTENNA CUTTING CHART............................................................................................................................33
OPERATING FREQUENCIES............................................................................................................................... 34
ZAXNET REMOTE CONTROL AND TIMECODE...............................................................................................................................................34
UHF AUDIO.........................................................................................................................................................................................................34
SPECIFICATIONS ................................................................................................................................................. 35
PRODUCT SUPPORT ........................................................................................................................................... 37
CONSUMER ALERT ..............................................................................................................................................................................................37
ZAXCOM WARRANTY POLICY AND LIMITATIONS ....................................................................................38

3
Knowing your TRX-900AA
1. SSMA Antenna Connector
2. Media Slot Media Slot
To insert a micro SD card, with the screen facing you, turn the card so the finger contacts are facing
to you and down toward the slot. Insert it into the slot and press it down until you here a slight click.
To remove it, press the card in until you hear the same click again.
3. Power Switch
The switch position to the left is OFF and to the right is ON. But if using external power via an STA
adaptor the left position “EXT” is ON.
4. Microphone / Input connector.
5. Dual color Status LED
•Green - Unit is on.
•Red - Unit inexpediently stopped recording.
•Green / Red flickering - Unit is recording.
1 23 4
5
6
7
8
9

4
6. INC / Record Key
•Increases the parameters of a menu item.
•When in the Home Screen pressing and holding it with the Home Screen Record enabled will put
the TRX into record.
•When in the Transport Control Screen while not recording will cause the TRX to play back.
•Press it while playing back to fast forward.
•Press and hold while in the Transport Control Screen to advance to the next segment.
•Press it in the Home Screen to display the current segment number.
7. DEC / Stop Key
•Decreases the parameters of the menu items.
•When in the Home Screen pressing and holding it with the Home Screen Record enabled will stop
the recording.
•When playing back from the Transport Control Screen will cause the TRX to stop.
•Press and hold while in the Transport Control Screen will jump back to the previous segment.
•Holding it while playing back will take you to the start of that segment.
8. Menu Key
•Press it will access the Menu
•Press it again will take you to additional Menu items
•Pressing it while powering up will take you into the Extended Menu
9. Battery Compartment
The TRX-900AA will use 2 AA batteries. You can use alkaline, Lithium or NiMH batteries

Zaxcom TRX-900AA Manual Home Screen
5
Home Screen
Frequency – This is theUHF transmit frequency of the TRX-900AA.
If the transmitter is being used in RECORD ONLY mode “NOTX”will be displayed.
ZaxNet Status
•RX – The transmitter is set to receive ZaxNet timecode and commands.
•TX – The transmitter is sending ZaxNet timecode and audio.
•JAM - The transmitter has jammed timecode.
Transport Status - Displays the current mode of the recording feature.
•STOP – Recording / Playback is stopped
•LREC – TRX is recording and LOOP RECORD mode is enabled
•REC – TRX is recording and NON-LOOP RECORD mode is enabled
•WAIT – May appear just before going into record, or if the card is ejected while recording.
Input Audio Meter- Displays the modulation of the inputted audio signal.
In the case of a TRX-900AA with an STA adaptor if the transmitter is set to STEREO mode you would
see both the left and right audio levels.
Gain - “G” Appears when the transmitter is receiving change of gain commands via ZaxNet.
When in the home screen:
•Press and hold the INC key to display the number of record segments are on the card.
Note that regardless of the size of the card it is limited to 256 segments.
•Press and hold the DEC key to display the current battery voltage
•If Home Screen Record is enabled the INC and DEC keys can be used to start the internal recorder.
567.4 RX STOP
ZaxNet Transport
Frequency Status Status
Battery Input Audio Meter Gain
Level Meter Indications
-20, -10, 0 dBFS
G

Zaxcom TRX-900AA Manual Main Menu
6
Main Menu
Navigating the Main Menu
•Press the MENU Button to enter the menu.
•To advance to the next menu press the MENU Button again.
Exiting the Main Menu
•To exit the menu at any time press and hold the MENU button for 1.5 seconds
Audio Gain
Analog Gain Digital Gain
This menu sets the gain of the incoming audio. The meter indicates the audio signal it is displayed
horizontally from left to right. If the TRX-900AA has an STA-100 / 150 (analog) attached this menu will not
be functional. In that case the gain is adjusted on the trim pots on the STA. In the case of a STA-042
(digital) the gain would be adjusted with the digital gain menu. The digital gain menu will replace the
analog menu.
UHF Transmit Frequency
This menu sets the UHF transmit frequency of the transmitter.
•Short presses of the INC or DEC key causes the value to change by 0.1 MHz.
•Holding the INC or DEC key causes the value to change by 0.5 MHz.
Transport Control
This page displays the transport status of the transmitter.
The top line displays the current mode: REC, PLAY or STOP followed by the timecode.
The bottom line contains the segment number and the audio level.
Playing back from the transport screen
•Pressing the INC key while stopped will play the segment that is displayed.
•Pressing the INC key while in play mode will fast forward.
•Pressing the DEC key while playing back will stop the playback.
•Holding the DEC key while playing back will take you to the start of that segment.
•Pressing the DEC key while stopped will rewind.
GAIN 20dB
TXFREQ 567.4
STOP 01:02:34:01
001
DGAIN 20dB

Zaxcom TRX-900AA Manual Main Menu
7
Timecode Frame Rate
This menu sets the timecode frame-rate that will be recorded.
The TRX-900AA will lock to and record all standard timecode frame rates.
•23.98, 24, 25, 29.97DF, 29.97DF, 30 DF, 30 NDF
IFB Earpiece Select
This menu sets what audio will be outputted from an STA audio out connector or EA-100 adaptor.
•REC/PLAY - Outputs the audio from the SD card - this is the audio that is either currently being
recorded or playing back.
•IFB RX AUDIO - Outputs the audio that is being received from ZaxNet IFB.
•IFB MIX ALL - Outputs a mix of the recording / playback audio and the IFB audio.
•IFB MIX REMOTE - This setting is not functional in the TRX-900AA.
Time Left
This page displays the remaining time left on the card and the time already recorded on the card.
This page will not be displayed if no card is present.
Lock Page
This page enables a lock function to prevent any accidental changes.
When you land on this page the countdown clock will begin. After 5 seconds the
transmitter will lock and the display will indicated LOCKED.
If you exit this screen before the 5 seconds is up the transmitter will not lock.
Even though the key’s will be locked you can press the INC or DEC key to temporarily display the
current battery voltage in place of the battery icon.
To Unlock
•Simultaneously press the MENU and INC keys.
Or
•Powering down the unit will clear the lock.
TIMECODE 23.98
GEN 01:02:34:01
Countdown clock starting at 5 seconds
After the transmitter locks
LOCK 5
LOCKED
01:02:34:01
IFB EARPIECE
REC/PLAY
TIME LEFT 20H
TIME USED 4H

Zaxcom TRX-900AA Manual Extended Menu
8
Extended Menu
Navigating the Extended Menu
•Press and hold the MENU key while powering up the unit.
•Pressing the MENU key will advance you to the next menu item.
Exiting the Extended Menu
•Cycle the power
Or
•Hold down the MENU key to get back to the EXTENDED MENU home page then press the INC key.
High Pass Filter Adjust
This menu turns on and adjusts the frequency of the high pass filter.
•The high pass filter range is 30Hz to 220Hz in 10Hz increments.
Limiter
This menu enables/disables and adjusts the limiter. The limiter is pre analog to digital converter.
•Range: -2dB to -30dB in 1dB increments.
When the input signal is too high the audio can clip and results in distortion and popping. The limiter
can be used to prevent clipping.
N
1K Notch Filter
This menu enables/disables the 1K notch filter.
The 1K notch filter is used to eliminate a 1K the test tone being outputted to the STA adaptor or EA-100.
HIGH PASS: OFF
Level when the limiter will act.
LIMITER: OFF
LIMITER: -10dB
FROM FULL SCALE
NOTE:
If you have a STA adaptor attached and you are transmitting in stereo mode - the limiter will be
disabled.
1K NOTCH FILTER
OFF

Zaxcom TRX-900AA Manual Extended Menu
9
2K Notch Filter
This menu enables/disables the 2K notch filter.
The 2K notch filter is useful in removing digital RF interference that can be introduced into the
microphone.
UHF Signal Format
This menu adjusts the transmission format
•US MONO - This format is used for mono transmission. It is used by customers in the US and other
countries where a 200 kHz channel is legal.
This setting will be used with 0=US on the Zaxcom ENG receiver or NORMAL on the QRX
•STEREO -This format is used for stereo transmission of a TRX-900AA. It is used by customers in the
US and other countries where a 200kHz channel is legal
This setting will be used with 2=ST on the Zaxcom ENG receiver or NORMAL on the QRX
•EUROPEAN -This format is used for European customers and other countries where a normal width
channel is NOT legal.
This setting will be used with 1=EU on the ENG Zaxcom receiver or NARROW on the QRX
•US MONO-R -Similar to US MONO. This can be used to force mono audio to the right channel.
This setting will be used with 0=USon the Zaxcom receiver
UHF Transmitter Power Level
Available on a TRX-900AA running software version 8.10 or higher
This menu adjusts the UHF transmit power of the transmitter.
•The TRX-900AA can be set at 10, 25, 50mW
TX FORMAT:
US MONO
TX POWER: 50 MW
IMPORTANT: If the Transmission Format set here and the Reception Format on the associated receiver
do not match, the receiver will be unable to correctly decode the audio from this transmitter.
IMPORTANT: Any change to this page REQUIRES a reboot before the new setting takes effect.
2K NOTCH FILTER
OFF

Zaxcom TRX-900AA Manual Extended Menu
10
.
IFB Receive Mode
Available on a TRX-900AA running software version 8.10 or higher
This menu will allow the TRX to receive ZaxNet commands.
•OFF – The transmitter will not receive any ZaxNet commands
•RX- The transmitter will receive ZaxNet commands
IFB Voting Enable
Available on a TRX-900AA running software version 8.10 or higher
This menu allows you to enable / disable the IFB Voting function.
The purpose of voting is to allow transmitter to choose and switch to the stronger signal from two
different ZaxNet transmitters. One purpose of this is if you are on a large set you can place a second IFB
transmitter at a different location and the TRX will choose the stronger signal. Just set the second IFB
transmitting frequency to exactly 2MHz higher than the first unit.
RXMODE=RX
NOTE: If the IFB RX to TX setting is set anything other than Normal you will not be allowed to set
this setting to OFF.
NOTE: This Page only will appear if you have the IFB RX TO TX mode set to NORMAL RX and RX MODE
is not set to OFF. Meaning that if the TRX-900AA will ever be in a transmit mode IFB voting no longer
applies and will not be available.
IFB VOTING
NORMAL (OFF)
NOTE: If this is set to OFF the next 6
ZaxNet menu items will not appear.

Zaxcom TRX-900AA Manual Extended Menu
11
IFB Receive to Transmit time
Available on a TRX-900AA running software version 8.10 or higher
This menu sets how long after power up that the transmitter will search for ZaxNet timecode before it
begins transmitting IFB audio for monitoring purposes.
ZaxNet IFB Receive Frequency
Available on a TRX-900AA running software version 8.10 or higher
This is where you set the ZaxNet receive frequency.
•This frequency is the frequency that the transmitter will receive wireless ZaxNet TC and commands as
long as this frequency matches the frequency of the corresponding ZaxNet transmitter - which can be a
Nomad or IFB100/200.
•This frequency is the frequency that the transmitter will receive TC from another TRX transmitter or a
ZFR recorder as long as this frequency matches the frequency of the corresponding transmitter.
The TRX will receive ZaxNet only
and NOT transmit ZaxNet TC and audio.
Adjustable from 1 up to 20 Seconds.
After boot up the TRX will search for a
ZaxNet signal for XX seconds before it
begins to transmit ZaxNet TC and Audio
IMPORTANT:After changing this setting a re-boot is required
IFB RX TO TX:
NORMAL RX
IFB RX TO TX:
20 SECS
IFB RX TO TX:
0 SECS: TX ONLY
The TRX will transmit ZaxNet TC and
audio only and will NOT receive
wireless TC.
When the TRX is receiving a ZaxNet signal you will also see:
ZaxNet signal frequency and RX shows that it is being
received
Signal strength meter
l h
RXFREQ: 2.403
RX
SIGNAL: 28
RXFREQ: 2.403

Zaxcom TRX-900AA Manual Extended Menu
12
ZaxNet IFB Transmit Frequency
Available on a TRX-900AA running software version 8.10 or higher
This is where you set the ZaxNet transmit frequency. This is the frequency that the transmitter will
broadcast timecode and ZaxNet audio on for the purpose of confidence audio monitoring via an ERX
receiver or Nomad. Note - the expected range will be less than 30 feet.
IFB Dropout Compensator
This menu will only appear if the TRX-900AA IFB is set to receive ZaxNet.
This is where you enable /disable the IFB drop out compensator.
The drop out compensator looks at the received audio surrounding a short duration drop out and replaces
the lost audio with audio that will match together the audio surrounding the drop out.
IFB Receive Pulse
Available on a TRX-900AA running software version 8.10 or higher
This menu will only appear if the TRX-900AA IFB is set to go into transmit mode.
This is where you set how often the transmitter will search for Timecode while operating.
When enabled this tells the transmitter to leave ZaxNet transmit mode once every XX seconds to go into
receive mode so it can re-jam its timecode wirelessly via ZaxNet. This has no affect on the UHF audio
transmission.
•The settings are NEVER or any interval between 10 and 999 seconds.
NOTE: When the TRX-900AA searches for TC it will temporally go out of transmit mode for
approximately 1 second as it receives a TC signal.
Note: You would need to use this setting if you
are monitoring audio via an ERX receiver and
you still want the transmitter to update TC
IFB RX PULSE:
NEVER
IFB RX PULSE:
600 SECS
IFB TX FREQ:
2.420
IFB DROPOUT
COMPENSATOR ON

Zaxcom TRX-900AA Manual Extended Menu
13
Power-Up Mode
This menu determines if the keys will lock after power-up.
•LOCKED – After power-up has completed, the transmitter will automatically go into Lock Mode to
prevent accidental changes to the settings.
•UNLOCKED – The keys are unlocked upon power-up. You can always lock the keys by going in to the
Lock Screen in the Main Menu.
Unlocking the Transmitter
Simultaneously press the MENU and INC keys.
Format Recording Card
This menu will allow you to erase and format the micro SD card.
NOTE: This menu will only appear if a card was inserted prior to booting up. Also if the micro SD card
is removed this page will not appear.
To Format a Card:
1. Before formatting the card, you may want to name the transmitter. Naming the card makes it easier
to differentiate files from different recorders - for example you can name the card with the talents
name. The NAME menu is located at the end of the Extended Menu (page 19 of this manual).
2. With the power ‘OFF’, insert the memory card into the media slot with the label to the back of the
unit. Press it all the way in till it “clicks”.
3. Power up the transmitter while holding the Menu key to enter the Extended Menu.
4. Advance to this menu.
5. Press the INC key 5 times.
6. You will see “FORMATTING FAT 32”
7. The TRX will displays “SUCCESS” or “FORMAT FAILED ERROR”
8. If “SUCCESS” appears power cycle the TRX and make sure the unit will record.
NOTE: If you see a “FORMAT FAILED ERROR” try to re-format the card and if it fails again DO NOT
use that card in the transmitter.
IMPORTANT: Even though many cards are sold preformatted, you must format the card in the
transmitter prior to recording. Only cards formatted in the unit will work properly.
POWER UP MODE:
LOCKED
PRESS UP KEY 5X
TO ERASE CARD

Zaxcom TRX-900AA Manual Extended Menu
14
Time Code Jam Mode
If you are using record run timecode this menu controls weather the TRX-900AA will go into record when it
receives running timecode.
•AUTO-JAM NORMAL– The TRX will continuously jam timecode via ZaxNet.
•AUTO-LOAD REC RUN – The TRX will continuously jam timecode via ZaxNet and will start and stop the
recording if the unit is receiving record run timecode.
In this mode the transmitter will go into record mode when it detects rolling timecode. And the will stop
when the timecode stops. If timecode is lost because the IFB signal is too weak the unit will not stop but
will continue in whatever state it was in until the timecode signal is restored.
Time Code Source
This menu selects how the TRX-900AA will receive its timecode.
•IFB (RF)– The transmitter will receive timecode via ZaxNet being broadcast from Nomad, an
IFB100/200, another TRX transmitter or a ZFR recorder.
•AUDIO INPUT– The transmitter, with a proper cable, will receive timecode via the microphone input.
•SIDE CONNECTOR - The transmitter will receive its timecode from the timecode in connector from the
STA adaptor or TCA-100.
When timecode is connected, it takes the transmitter approximately three seconds to recognize the TC.
The screen displays TIME CODE followed by JAM when it is recognized. When the word JAM disappears,
the timecode input source can be disconnected and normal operation can be resumed.
Time Code Output
This menu selects how the TRX-900AA will output timecode on the 3.5mm connector on a STA adaptor.
•OFF- No timecode will be outputted on the STA and audio will be sent on the connector.
•ON: OUT LEFT- Time code signal will be on the tip of the 3.5mm connector (Left) and will replace the
audio out.
•ON: OUT RIGHT -This setting is not applicable to the TRX-900AA.
•ON: OUT BOTH -This setting is not applicable to the TRX-900AA.
TC JAM MODE:
AUTO-JAM NORMAL
TC SOURCE:
IFB (RF)
NOTE: When using the mic input connector, the audio level of the timecode signal needs to be
between -30 and -10 dBFS on the unit’s meter. Any level above -10 may cause clipping, which will
prevent proper reading of timecode.
TIMECODE OUTPUT:
OFF

Zaxcom TRX-900AA Manual Extended Menu
15
Group ID
This allows you to set your TRX-900 to a “GROUP” to be controlled via ZaxNet.
So for example a transmitter set to Group 1 will control all Group 1 receivers and a Group 2 transmitter
will control all Group 2 receivers. This allows you to control a group of receivers without affecting others.
This will also help if two or more people on set are sending ZaxNet commands each person will be
independent and won’t interfere with each other. Most users leave this set to 1 on all their Zaxcom
products.
Group codes can be set from 1 to 99
Unit ID
This assigns a unique number identify the TRX-900 within a particular group. This allows individual devices
in one group to be independently controlled.
You can assign a number from 1to 200
REMOTE CONTROL
GROUP ID = 1
REMOTE CONTROL
UNIT CODE=ALL

Zaxcom TRX-900AA Manual Extended Menu
16
Dynamics
The Dynamics is a soft knee compressor that is located after the analog to digital converter. The Dynamics
will limit the dynamic range to prevent clipping during occurrences of loud audio.Dynamics is comprised
of both a compressor and an expander, which operate jointly. The Compressor in Dynamics can set to
mild or extreme compression and features a soft knee for more transparent operation.
To enter the Dynamics Menu
Press the INC or DEC key - “PARMS” will be displayed on the right.
To move to the next parameter, press the MENU key.
To exit this page, hold the MENU key for 1 second.
Dynamics Parameters
•PARMS(Parameters): OFF / ON: This turns the entire compressor/expander on or off.
•Link L-R: OFF / ON: This links the left and right of a stereo unit. So if one side of the signal needs
compressing / expansion the other side will kick in to match.
•SPEED (Decay Speed) : SLOWEST / SLOW / NORMAL / FAST / FASTEST
Sets the speed in how gradual the decrease of signal level happens immediately after a signal reaches its
peak. This is typically set to FAST.
•ATTACK (Attack Speed) :SLOWEST / SLOW / NORMAL / FAST / FASTEST
Sets the speed in how fast the gain is turned down once the signal exceeds the threshold setting. This is
typically set to FAST.
•CMP RATIO (Compressor Ratio):Valid range: 1.0: to 5.0:1, In 0.1 steps.
The amount of gain reduction is determined by the ratio setting.
A compressor ratio for example of 2.0:1 means for every 1 dB above the compressor threshold the gain
will be reduced 2 dB. A higher ratio setting makes the compressor more aggressive.
•CMP THRESH (Compressor Threshold): Valid range: 0to –96dB, in 1dB steps.
Sets the level which gain reduction occurs. This is typically set to -12dB from full scale.
•CMP KNEE:(Compressor Soft Knee): Valid range: 0to 20dB, In 1dB steps.
Sets the compressor's soft knee. A soft knee reduces “softens” the audible change from uncompressed
to compressed, especially for higher ratios where the changeover is more noticeable
•EXP RATIO (Expansion Ratio):Valid range: 1:1.00 to 1:4.00, In 0.01 steps
Sets the expansion ratio. For example a1:2.0 expansion ratio means for every 1 dB below the expansion
threshold the gain will be reduced 2 dB.
•EXP THRESH (Expansion Threshold):Valid range: 0to –96dB, in 1dB steps.
Sets the threshold above which gain reduction occurs. This is typically set to -80dB.
•REDUCE (Expander Gain Reduction):Valid range: 0to –36dB, in 1dB steps.
Sets the limit on the amount of gain reduction caused by the expander. This is typically set to -6dB.
•GAIN (Make-up Gain):Valid range: 0to 30dB, In 1dB steps.
Used to compensate for the gain reduction caused by the action of the compressor. Because the
compressor is reducing the gain (or level) of the signal, the ability to add a fixed amount of make-up gain
at the output is provided so that an optimum level can be used.
Dynamics OFF
When the Parameters are ON you can adjust the
Dynamic Menu
DYNAMICS
DYNAMICS PARMS
ON

Zaxcom TRX-900AA Manual Extended Menu
17
Analog to Digital Converter
This menu sets where the analog audio signal is converted to a digital signal.
•STA-100 - This setting is used when feeding audio into a STA-100
•STA-150 - This setting is used when feeding audio into a STA-150
•STA-042 - This setting is used when feeding digital audio into a STA-042
•INTERNAL - This setting is used when analog microphone attached to the microphone connector.
Battery Type
This menu adjusts the battery type you are using so the receiver can properly display the remaining
battery capacity.
•The settings are NIMH, Lithium and Alkaline (Displayed as “ - - - -“)
Recording Mode
This adjusts what the transmitter will do after you reach the record capacity of the card.
•NON-LOOP RECORD (recommended setting) - Once the card has filled up, recording will stop and FULL
will be displayed. This prevents over-writing any portion of the audio.
•LOOP RECORD - Once the media has filled up, the new audio will begin over-writing the oldest audio on
the card.
BATTERY TYPE:
NIMH QRX
RECORD MODE:
LOOP RECORD
NOTE: In the menu you will see “ENG” and “QRX” options for these battery types as well. This is so
each type Zaxcom receiver model“ENG” RX-900 or “QRX” QRX-100 can correctly display the
transmitter’s battery level.
ADC: STA-100
IMPORTANT: Any change to this page REQUIRES a reboot before the new setting takes effect.

Zaxcom TRX-900AA Manual Extended Menu
18
Boot Up Mode
•REMOTE STANDBY – The transmitter boots up in Low Power Standby mode. The TRX-900AA will be
waiting for a ZaxNet “WAKE” command to come up to full power.
•STANDBY MODE – The transmitter boots up in Low Power Standby mode. The TRX-900AA will be
waiting for you to Press Menu to come up to full power.
•NORMAL MODE – The transmitter will boot up in Normal mode.
Mute Switch
This enables /disables the MSA-100 Mute Switch. The mute switch cuts out the UHF transmitted audio
while maintaining the UHF signal.
•OFF- Mute switch is disabled.
•ENABLE POSITIVE -Mute switch is enables and functions in its normal position.
•ENABLE NEGATIVE - Mute switch is enabled and the switch function is reversed.
Left Right Switch
This menu turns on the left / right switch mode.
This function allows the wireless user to cause the audio to switch from the left output to the right output
of a stereo RX900 receiver when the key is pressed.
You can select the UP, DOWN, or MENU key to act as the trigger.
Side Tone Gain
This boosts what audio level is being fed to the EA-100 or the audio output of an STA adaptor.
•This is user selectable to 0db, +6dB, +9dB, +12dB.
BOOT UP IN
NORMAL MODE
LR SWITCH MODE
OFF
NOTE: This is only compatible with the RX900S Receiver
MUTE SWITCH:
DISABLED
SIDE TONE GAIN
OdB

Zaxcom TRX-900AA Manual Extended Menu
19
IFB Remote Control
This menu will not appear if the IFB settings allow the TRX to go into transmit mode.
This menu turns ON / OFF if the TRX-900AA will accept remote control commands via ZaxNet.
IFB Jam Threshold
This menu sets how much the timecode has to jump before a new record file is forcibly created.
IMPORTANT: When a new file is created, while a take is in progress, about a half of second of the
audio will be lost.
QRX Program
This is used to update the software on a QRX-100.
To Update the QRX Software:
1. With a computer copy the QRX software onto a formatted micro SD card.
2. Place the card in the transmitter
3. Power up the transmitter.
4. Advance to this menu.
5. Press the INC key.
6. The transmitter will begin to transmit the software to a QRX-100 that is set to receive the software.
The transmitter will continually resend the program until you manually stop it.
Home Screen Record / Stop
This allows the TRX-900AA to use the INC and DEC keys to start the internal recorder from the HOME
SCREEN.
If this is turned ON when in the Home Screen:
•Press and hold the INC key for 1.5 seconds the TRX-900AA will start recording.
•Press and hold the DEC key for 1.5 seconds the TRX-900AA will stop recording.
PRESS TO SEND
QRX PROG FILE
IFB JAM THRESH
1000 MS (DEFAULT)
ALLOW IFB REMOTE
CONTROL: ON
ALLOW HOME SCRN
REC-STOP: ON