User Manual

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Squelch Mutin g of audio circuits wh en received sign al levels fall below a pre-
determ in ed value.
SRAM Static-RAM ch ip used for volatile, program /data m em ory.
SSI Syn ch ron ous Serial In terface on th e DSP56001 con sistin g of six sign als an d
used for an RX an d TX m odulated data in terface to th e ADSIC.
St andby M ode An operatin g m ode wh ereby th e radio is m uted but still con tin ues to m on itor
data.
Syst em Cent ral
Cont rollers
Main con trol un it of th e trunked dispatch system ; h an dles ISW an d OSW
m essages to an d from subscriber un its (see ISW an d OSW).
Syst em Select Th e act of selectin g th e desired operatin g system with th e system -select switch
(also, th e n am e given to th is switch ).
TOT Tim e-Out Tim er; a tim er th at lim its th e len gth of a tran sm ission .
TSOP Th in Sm all-Outlin e P ackage
UART Un iversal Asyn ch ron ous Receiver Tran sm itter.
µC Microcon trol un it (see MCU).
VCO Voltage-Con trolled Oscillator; an oscillator wh ereby th e frequen cy of
oscillation can be varied by ch an gin g a con trol voltage.
VCOB IC Voltage-Con trolled Oscillator Buffer IC
Vocoder VOice en COD ER; th e DSP-based system for digitally processin g th e an alog
sign als, in cludes th e capabilities of perform in g voice com pression algorith m s
or voice en codin g.
VOCON VOcoder/CONtroller board
VSELP Vector Sum Excited Lin ear P redictive codin g; a voice en codin g tech n ique
used in ASTRO digital voice.
VSW R Voltage Stan din g Wave Ratio