RELM Communications Inc SRU50ABC ユーザーズマニュアル
S Series Repeater USER MANUAL
©RELM Communications Inc. Revision 1.0
7
Introduction
The SR35/50 series of radio systems employ state of the art design and construction methods to deliver a range of
high performance, ultra reliable radio devices. They are ideally suited for use in VHF or UHF two way voice radio
systems, however the SR35/50 can perform any number of applications where the added advantage of linear
frequency and phase response from DC to 5KHz can be utilized. The SR35/50, unlike conventional PLL radio
systems, uses a two point modulation method synthesizer for extended low end VF transmit frequency response.
high performance, ultra reliable radio devices. They are ideally suited for use in VHF or UHF two way voice radio
systems, however the SR35/50 can perform any number of applications where the added advantage of linear
frequency and phase response from DC to 5KHz can be utilized. The SR35/50, unlike conventional PLL radio
systems, uses a two point modulation method synthesizer for extended low end VF transmit frequency response.
The flexibility of the SR35/50 series allows them to be configured for a wide range of applications, including;
•
Standard or wideband voice, full duplex radio.
•
Cellular or Trunking systems.
•
POCSAG paging transmitter.
•
Direct FSK modulation.
•
2 or 4 level FSK transmissions.
•
Other paging formats.
•
Cross band link or repeater.
General Description
The SR35/50 series features a high degree of RFI and EMI screening throughout their design and construction. The
receiver and exciter (low power transmitter) modules are contained in a solid machined aluminum enclosure, and for
additional screening each interface pin is individually filtered. The PA module is contained in a special compact
extrusion for minimum harmonic radiation. In addition to this the RF modules and the micro controller are also
contained in the main screened 2RU case for low conducted and radiated emissions and minimal susceptibility to
RFI and EMI.
The SR35/50 series consists of four main sub assemblies as outlined below: an Exciter Module, a Receiver Module,
a Power Amplifier Module and a Micro Controller board. For further information on these sub assemblies, refer to
the Technical Description section later in this manual.
receiver and exciter (low power transmitter) modules are contained in a solid machined aluminum enclosure, and for
additional screening each interface pin is individually filtered. The PA module is contained in a special compact
extrusion for minimum harmonic radiation. In addition to this the RF modules and the micro controller are also
contained in the main screened 2RU case for low conducted and radiated emissions and minimal susceptibility to
RFI and EMI.
The SR35/50 series consists of four main sub assemblies as outlined below: an Exciter Module, a Receiver Module,
a Power Amplifier Module and a Micro Controller board. For further information on these sub assemblies, refer to
the Technical Description section later in this manual.
Exciter Module Description
The Exciter module features a modulation bandwidth to DC with an ultra wide RF bandwidth 20MHz to 1000MHz
at an output power of 300mW. To change from one band to another, all that is required is to change the plug in VCO
board, no other manual adjustment or change is required. Should a high stability reference be required, the RF
modules can be fitted with connectors for an external reference oscillator input. On board memory stores calibration,
personality information and program data. Alternatively, the exciter module can be set up as a conventional PLL
should simplicity and minimum cost be required. The fractional N synthesizer provides ultra low spurious while still
maintaining fast lock times even at 6.25KHz step size or less. An optional built turn around mixer (TRM) provides
advanced diagnostics such as receiver sensitivity tests.
at an output power of 300mW. To change from one band to another, all that is required is to change the plug in VCO
board, no other manual adjustment or change is required. Should a high stability reference be required, the RF
modules can be fitted with connectors for an external reference oscillator input. On board memory stores calibration,
personality information and program data. Alternatively, the exciter module can be set up as a conventional PLL
should simplicity and minimum cost be required. The fractional N synthesizer provides ultra low spurious while still
maintaining fast lock times even at 6.25KHz step size or less. An optional built turn around mixer (TRM) provides
advanced diagnostics such as receiver sensitivity tests.