Instruction Manual

UHF Digital Hybrid Wireless
®
Rio Rancho, NM
5
General Technical Description
SmartDiversity
™
allowseachreceivertorunindepen-
dentlytoprovidetwoseparateaudiochannels.The
algorithm analyzes both the incoming RF level and the
rateofchangeinRFleveltodeterminetheoptimum
timingforphaseswitching,andtheoptimumantenna
phase.Thesystemalsoemploys“opportunisticswitch-
ing”toanalyzeandthenlatchthephaseinthebest
positionduringbriefsquelchactivity.
Ratio Diversityblendstheaudiooutputsofbothreceiv-
ersinaseamlessmannertoproduceasingleaudio
output.Apanningcircuitblendsmoresignalfromthere-
ceiver with the stronger RF signal over a wide RF level
rangetoanticipateandeliminatedropoutslongbefore
theyoccur.WhenagoodRFsignalispresentatboth
receiversandtheaudioisblendedequally,thesignal-
to-noiseratioisincreasedby3dB.
Thedesignconsistsoftwoseparatereceiversbuiltinto
asingle,ultracompacthousingwithinterchangeable
adaptersforvideocamerawirelessreceiverslotsand
stand-aloneuse.DigitalHybridWireless
®
technology
providessuperb,compandor-freeaudioqualityand
compatibilitywithotherwirelesssystems.TheRFper-
formanceisextremelystableoveraverywidetempera-
turerange,makingthereceiverperfectlysuitedtothe
roughenvironmentalconditionsfoundineldproduc-
tion.
Thefrontpanelfeaturesamenu-drivenLCDinterface
and four membrane switches used to view and alter set-
tings.Audiooutputsareprovidedontherearpanelfor
camera slots or other audio devices, and in the case of
theSRb5P,alsoonthefrontpanelthrougha5-pinTA
Series connector.
Abuilt-inspectrumanalyzerscansacrossthetuning
rangeofthereceivertosimplifyndingclearoperating
frequencies.
RF PCB Block Diagram
Audio PCB Block Diagram
Ref. Osc
SAW
filter
RF amp
Splitter
Phase
combiner
Mixer
IF
amp
SAW
filter
SAW
filter
IF
amp
Rx IC
250 kHz
RSSI
Window
detect
Audio 1
Pulse
detector
1st
VCO
2nd
VCO
PLL
µP
SAW
filter
RF amp
Splitter
Mixer
IF
amp
SAW
filter
SAW
filter
IF
amp
Rx IC
350 kHz
RSSI
Window
detect
Audio 2
Pulse
detector
1st
VCO
2nd
VCO
PLL
µP
Receiver 1
Receiver 2
High side
injection
High side
injection
SR Dual Receiver RF Board
Phase
combiner
248.450
MHz
243.950
MHz
µP
DSP
Keypad
LCD
display
DAC
Codec
Memory
Ref xtal
Audio 1
Audio 2
(from RF PCB)
To both PLL
To phase switches
Audio amps
Digital pot
Digital pot
µP
digital
atten
CH 1
audio switch
CH 2
audio switch
Fuse
Camera
power in
Osc
sync
DC-DC
conv
DC-DC
conv
DC-DC
conv
On/O
–5V
+5V
Osc
sync
+1.6V
+3.3
V Reg
+3.3V
5k
5k
50
50
+
–
Com
Hi
Lo
+5V
+5V
5k
5k
50
50
+
–
Com
Hi
Lo
+5V
+5V
Diode
protected
outputs
1
2
3
4
5
µP
polarity