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Williams AV FM 557 FM Plus Large-Area Dual Assistive Listening System w/ R37 Receivers

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FM Plus Large-area Dual FM and Wi-Fi assistive listening system with 4 FM R37 receivers.System Includes: (1) FM T55 transmitter (4) PPA R37N receivers (4) EAR 022 surround earphones (2) NKL 001 neckloops (1) IDP 008 ADA wall plaque Read More

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FM Plus Large-area Dual FM and Wi-Fi assistive listening system with 4 FM R37 receivers.

System Includes:

  • (1) FM T55 transmitter
  • (4) PPA R37N receivers
  • (4) EAR 022 surround earphones
  • (2) NKL 001 neckloops
  • (1) IDP 008 ADA wall plaque

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Product Specs

EAR 022
StyleAround-ear speaker
Plug3.5mm mono
Driver Size23 mm
Nominal Impedance32 ?
Freq. Response20 -20kHz
Max Power Input30 mW
Sensitivity118 dB @ 1kHz
FM T55
Dimensions8.45" W x 8.25" D x 1.72"H (21.5 cm x 21 cm x 4.4 cm)
WeightTransmitter: 3.2 lbs (1.45 kg)
ColorBlack/Silver with silver legends on the front, white legends on the back
Rack MountStandard 19" Rack, one EIA rack space high, 1/2 space wide
1 - 2 units can be mounted in a single rack space with optional RPK 005 (single) or RPK 006 (double) Rack Mount Kits
Power SupplyDesktop Style Transformer (TFP 062); Input: 100-240 VAC, 50/60 Hz. IEC Line Cord; Output: 24 VDC, 750 mA, 18W. 2.5mm ID center positive barrel connector
Power ON IndicatorPush On/Push Off latching power button, backlit green indicates power ON, backlight off indicates power OFF, fading from bright to dark indicates Sleep Mode.
Temperature RangeOperating: +32° F to +104° F (0° C to 40° C); Storage: -4° F to +158° F (-20° C to 70° C)
User Interface3.12" High Resolution OLED display with selections via buttons. Hosted Web page. Remote control and monitoring
DanteOnly available on FM T55 D
EthernetRJ-45 on back of unit supports CAT 5e cable lengths up to 328 feet (100 meters); 10/100 Base-T IEEE 802.3 compliant, unique MAC address
RF Section
Operating Frequencies72.1-75.9 MHz , 17 wideband channels (selectable)
Frequency Accuracy± 2 ppm stability, 0-50? C
Deviation± 75 kHz maximum
Pre-Emphasis75 microsec
RF Field StrengthDoes not exceed 80 mV/m at 3 m
Compatible AntennasANT 005, ANT 021, ANT 024, or ANT 025
Transmission RangeUp to 1000 ft (304 m) with ANT 005 coaxial antenna mounted on rear chassis connector
RF Outputs(1x) #10-32 stud connector in center of unit (pcb mounted)
(1x) F-connector on rear chassis
RF Transmit Indicator1 Green LED, indicates RF "On Air"
RF PowerFull, Medium, Low or OFF indiacted by menu icon
RF Time Out (sleep mode)30 min. duration, 4 hr. duration, or Always On selected via menu. Starts when audio is below -18 dB level with no button pressed for selected duration
Audio Section
Audio Processor FunctionsDSP based; Compression: 1:1, 1.5:1 or 2:1; High-pass and Low-pass Filter Frequency control
Frequency Response31 - 16000 Hz, ±3 dB (Music Audio Preset)
Signal-to-Noise RatioGreater than or equal to 74 dB Transmitted RF
Total Harmonic DistortionLess than 0.25% @ 1 kHz (RF output)
Common Mode RejectionGreater than 57 dB @ 1 kHz, Mic or Line
Audio Inputs(1x) Combination 3-pin XLR, 1/4" (TRS) jack for balanced or unbalanced line level, or balanced or unbalanced microphone with selectable phantom power
Audio Input Gain AdjustIn menu, adjustable to 0 to -50 dB, in 1dB steps
Phantom Power14.4 VDC applied through 2.2 kOhms resistors to analog combo jack: Pin 2 and Pin 3 on XLR jack, or tip and ring on 1/4" TRS jack
Audio Level Indicators10-LED?array that reads -18 to +9 dB at 3 dB intervals. 7 Green, 2 Amber, and 1 red LED. Green LEDs indicate normal operating audio level peaks, Amber LEDS indicate close to overload peaks, Red LED indicates overload peaks
Headphone Output1/4" TRS stereo jack, mono signal, 15.7 mW, maximum in 33 ? (level adjustable in menu 0 to -40 dB in 2 dB steps)
Line OutputRCA jack (black), -10 dBV (.32 VRMS); Output impedance 100 ohms at +9dB
Input Levels (Bal or Unbal) (at Audio Input Gain = 0dB)
Nominal (1st Amber LED)Microphone: -55 dBV (1.7 mV RMS); Line: -25 dBV (55 mV RMS)
Overload Warning (Displayed on Screen)Microphone: -15 dBV (180 mV RMS); Line: +16 dBV (6.3 V RMS)
Absolute Max Rating*Microphone: +20 dBV (10.0 V RMS); Line: +20 dBV (10.0 V RMS)
ApprovalsFCC, RoHS3, WEEE, Industry Canada
Warranty2-year parts and labor
IDP 008
10-3/8" (L) x 6- 1/4" (W) x 1/8" (H)
NKL 001
Other ModelsNKL 001 S (3.5 mm stereo plug)
Dimensions4.1" x 2.85" x 1.38" (104 x 72 x 35 mm)
Weight4.6 oz (130 g) with batteries. 2.6 oz (73 g) without batteries
Battery Type(2) AA Alkaline or (2) x AA NiMH
Battery LifeTwo (2) AA non-rechargeable alkaline batteries (BAT 001), approx. 50 hrs
(2) AA rechargeable NiMH batteries (BAT 026), 1500 mAh, approx. 32 hrs
Current Consumption52 mA nominal
Temperature Range - 0 to 50 °C
Channels17, accessed via seek button in battery compartment
Operating Freq72.1, 72.2, 72.3, 72.4, 72.5, 72.6, 72.7, 72.8, 72.9, 74.7, 75.3, 75.4, 75.5, 75.6, 75.7, 75.8, 75.9 MHz
Intermediate Freq75 kHz
FM Deviation75 kHz
De-Emphasis75 µS
LED IndicatorPower: Green; Low Battery: Flashes Green
AFC Range± 120 kHz
Sensitivity2 µV at 12 dB Sinad with squelch defeated
Input Overload100 mV
Frequency Response200 - 15 kHz
ModulationFM, +/- 75 kHz peak deviation
Signal-to-Noise Ratio65 dB min @ 100 uV
Receive AntennaIntegral with earphone/headphone cord
Audio Output35 mW max, peak into 16 ohms
Output Connector3.5 mm stereo/mono phone jack
EarphoneEarbud-type with foam cushion, 3.5 mm plug, 32 ?
Auto Shut-offEnters sleep mode after approximately 6 mins of no RF signal
ApprovalsFCC, Industry Canada, RoHS, WEEE
WarrantyLifetime PLUS Limited Warranty, 90 Days on most accessories

NOTE: Specifications are subject to change without notice.
* Stresses above these ratings may cause permanent damage or degrade reliability.

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