Zaxcom TRX900 User Manual - Hardware and Accessories
Hardware and Accessories
Antenna
The transmitter uses a gold plated SSMA connector. Included is an antenna cut to the correct
length for your transmitter's specific frequency. The connector is a simple coaxial thread-on. It is
a good idea to periodically check that the connector is securely mounted.
Wire Clip
The TRX900 and TRX900AA transmitters use a wire belt clip. Attach the clip to the transmitter by
inserting the clip into the 2 holes in the sides of the transmitter. Hold the clip carefully in order to
not scratch the side of the transmitter.
MICROPHONES AND OTHER AUDIO INPUT
Sennheiser MKE2 Platinum
(Do not use the Gold model)
Countryman B6
Countryman EMW
DPA 4063
(ask for the Zaxcom 3.3v model)
Shure WL50
Other microphones will be added as soon as verification of 3.3v power performance and RF
interference susceptibility can be checked.
The Zaxcom transmitter has an unbalanced microphone input accessed through a 3 pin Micro-
Lemo connector. You can use an unbalanced dynamic microphone or a powered lavaliere.
Zaxcom recommends 3-wire lavalieres that utilize a separate ground pin, audio pin and power
pin.
If it is necessary to transmit a line level input, an inline pad will be required on the standard
dynamic microphone input cable (3 pin XLR to 3 pin Micro-Lemo).
48 Volt phantom microphone powering will require an external 48 Volt power supply when using
the TRX900 and TRX900AA. The MMT transmitter and TRX990 are the only Zaxcom transmitters
with a built in 48V supply.
Warning
Deneke 48 V power supplies will blow up the mic preamp of the transmitter
if they are connected to the transmitter when their power is switched on. The Deneke puts
a 48V spike into the transmitter when this happens. Please avoid this unit if at all possible.
When wiring a microphone it is necessary to connect the shield of the cable to the shell of the
Lemo connector as well as to the ground of the microphone. Separating some ground strands
and pressing them between the shell of the connector and the internal cable strain relief can
accomplish this. To avoid RF interference from getting into the audio it will also be necessary to
add a 200pF capacitor between Mic+ and Ground pins. A 0402 surface mount capacitor
(supplied with all connectors) should be fitted directly between the pins in the connector. If RF
noise is present in the audio then this connection procedure has not been followed properly or
there is a bad connection inside the mic connector.