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Williams Sound FM 558-12 PRO FM Plus Large-Area Dual Assistive Listening System w/ R38 Receivers

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FM Plus Large-area Dual FM and Wi-Fi assistive listening system with 12 FM R38 receivers. Features coaxial cable and rack panel kit for professional installation.System Includes: (1) FM T55 transmitter (12) PPA R38N receivers (12) EAR 022 surround earphones (3) NKL 001 neckloops (1) CHG 3512 12-b... Read More

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FM Plus Large-area Dual FM and Wi-Fi assistive listening system with 12 FM R38 receivers. Features coaxial cable and rack panel kit for professional installation.

System Includes:

  • (1) FM T55 transmitter
  • (12) PPA R38N receivers
  • (12) EAR 022 surround earphones
  • (3) NKL 001 neckloops
  • (1) CHG 3512 12-bay charger
  • (12) BAT 026-2 AA NiMH rechargeable batteries
  • (1) ANT 005 remote coaxial antenna
  • (1) IDP 008 ADA wall plaque
  • (1) RPK 005 rack panel kit

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Product Specs

ANT 005
Use withPPA T45, PPA T45NET, PPA T27 Transmitters
Connector typeF-connector
Cable typeRG 59 coax
Nominal Impedance75 Ohm
Total Cable Length22 ft
Active Antenna Length80in
BAT 026-2
NiMH, 1.2 Volt, 1500 mAh
CHG 3512
Size9.5"L x 7.4"W x 1.7"H (24.1 cm L x 18.8 cm W x 4.3 cm H)
Weight1.2 lbs (.54 kg), excluding power supply
ColorBlack ABS
Power Supply Input90 - 240 VAC input
Power SupplyTFP 037 Switching AC adapter, 5 VDC - 4A output
Charging Rate16 Hour Charge: 140 mA
Pulse/Maintain: 140 mA
Charging Time16 hours nominal
Unit Capacity12 Units
IndicatorsIndividual Charging Indicators: Red LEDs. LEDs blink when batteries are charged
Warranty1 year (cables and power supply warrantied for 90 days)
ApprovalsCE, WEEE, RoHS
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 (3.5mm stereo plug)
Dimensions4.1" x 2.85" x 1.38" (104 x 72 x 35mm)
Weight4.6oz (130g) with batteries. 2.6oz (73g) without batteries
ColorBlack/Silver. Black ABS Plastic case with Aluminum faceplate
Battery Type(2) AA Alkaline or (2) AA NiMH Rechargeable
Battery Life(2) AA non-rechargeable alkaline batteries (BAT 001-2), approx. 50 hrs.
(2) AA rechargeable NiMH batteries (BAT 026-2), 1500mAh, approx. 32 hrs.
Current Consumption52mA normal
Operating Temp. Range32° - 122°F (0° to 50°C)
Channels17 Wideband, accessed via menu
Operating Frequencies72.1, 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
FM Deviation75 kHz
De-Emphasis75 µS
Display Screen1" OLED
Power IndicationPower button, backlit green. Good battery strength - glows solid. Low battery - flashes
Sensitivity2 µV at 12 dB Sinad with squelch defeated
Input Overload100 mV
Frequency Response200 Hz - 15 kHz, ±3dB
ModulationFM, +/- 75 kHz peak deviation
Signal-to-Noise RatioMinimum 65 dB @ 1.0V
Receive Antennantegral with earphone/headphone cord
Audio Output5 mW max at 16 ?
Headphone Connector3.5 mm stereo jack, mono output for stereo or mono earphones/headphones
Supplied EarphoneStereo,earbud-type with foam cushion, 3.5 mm plug, 32 ?
Power Save ModeEnters sleep mode after approximately 3 minutes of no RF signal
ApprovalsFCC, Industry Canada, RoHS, WEEE
WarrantyLifetime PLUS Limited Warranty, 90 Days on most accessories
RPK 005
Other ModelsRPK 006 For mounting two 1/2-space products side-by-side in a single rack space

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

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