Technical Manual

Technical Manual
© SPECTRA ENGINEERING 2003 Revision 1.1.4 1
1. General Description
The MX950 series equipment is a cost effective professional solution with full sub
band capability. Packaged in an compact hand portable carry case suitable for instant
deployment. DMR applications use 6.25e kHz TDMA Tier 2, conventional mode
Repeater. Operating modes can be software upgraded to cater for feature and system
release updates.
The MX950 series employs state of the art design and construction methods to deliver
a range of high performance, very reliable radio base stations and repeaters. They are
ideally suited for use in VHF or UHF two-way voice communications radio systems.
Fractional synthesizers and the two-point modulation method give the added
advantage of linear frequency and phase response from DC to 3 kHz for accurate
reproduction of voice and low frequency digital signalling systems. The Receiver and
Exciter circuits are contained in single special aluminium housing together with the
associated audio processing and digital control on a single circuit board. The Power
Amplifier is also contained in its own extruded aluminium housing and can be easily
removed from the main chassis. The MX950 also incorporates ‘Plug and Play’
technology and performs automatic self-calibration. A complete module changeover is
field replaceable in very short time.
The MX950 employs some unique features in its design and much thought and
consultation has been used to provide a product that offers an extreme degree of
flexibility for the installer and service person. For example, all options may be easily
field retrofitted at a later date. In addition, servicing is simplified with PCB's having
all components on one side of the PCB. This permits the Technician to diagnose
problems while either still connected in the chassis or powered simply and
independently on the test bench.
The flexibility of the MX950 series allows it to be configured for a wide range of
applications without removing any covers.
Standard MX950 applications include:
Analog Voice Repeater
DMR Repeater
The MX950 incorporates special technical features, of which the key ones are listed
below:
Extremely low conducted emissions
Extremely low transmitter spurious
Fast transmitter on time
Transmitter frequency response down to DC
Low group delay distortion
Full sub band RF switching bandwidth
No re-tune design for receiver and transmitter
Fully software programmable
Built in diagnostics