Specifications, FAA Certification, Mounting, Cable

SPECIFICATIONS

Type

Electret condenser, noise canceling, with transistor pre- amplifier, DTMF signaling circuitry, illuminated keypad

Frequency Response

200 to 4,000 Hz (see Figure 1)

+10

±10

100

200

500

1,000

2,000

5,000

10,000

20,000

TYPICAL FREQUENCY RESPONSE

FIGURE 1

Polar Pattern

Bidirectional, noise canceling

Electrical Characteristics

	Operating Voltage
	8 V	12 V	28 V	Notes

Audio Output Level*				Audio trim-

Dimensions

See Figure 2

1.9 mm

(5/64 IN.)

40.4 mm

(1-19/32 IN.)

44.4 mm

(1-3/4 IN.)

42.6mm

(1±11/16 IN.)

25.4mm

(1 IN.)

64mm

(2-1/2 IN.)

70 mm

(2-3/4 IN.)

36.9mm (15/32 IN.)

101mm

(3-31/32 IN.)

(100 μbar acoustic	±11.5 dBV	±11.0 dBV	±10.0 dBV	pot in factory
test signal at 1	(266 mV)	(281 mV)	(316 mV)	preset	posi-
kHz, 10 mm)				tion

DTMF Output Level	±12.8 dBV	±12.0 dBV	±11.2 dBV	DTMF	trim-
	(230 mV)	(250 mV)	(275 mV)	pot in factory
				preset	posi-
				tion

Dc Supply Current{	6 mA	12 mA	36 mA

*Standard electrical test circuit per RTCA DO-170

{Microphone is powered only while PTT switch is depressed (standby current = 0 if PTT switch is released)

Environmental Conditions

Operating Temperature: ±40 to 60° C (±40 to 140° F)

Storage Temperature: ±54 to 85° C (±65 to 185° F)

Relative Humidity: 0 to 95% (non-condensing)

Microphone Connector

6-conductor modular telephone type

PTT Switch assembly

Mechanical: Double-pole, single-throw, leaf-type, nor- mally open

Cable

ALM-88, detachable MODULINK, 0.65 m (2.1 ft) coiled (1.8 m [6 ft] extended) cord with modular plug on micro- phone end and PJ-068 aircraft connector on equipment end

Construction

Case: Black textured high-impact ARMO-DUR

Switch Button: Black ARMO-DUR

Keypad: Molded silicone rubber

Hangup Loop: Matte finish stainless steel

OVERALL DIMENSIONS

FIGURE 2

Net Weight (including cable and connector) 283 g (10 oz)

Certification

FAA Certified for aircraft under TSO-C58a requirements

FAA CERTIFICATION

The Model 888TT is FAA Certified for aircraft use under FAA TSO-C58a requirements. To maintain this FAA Certifi- cation, any service required for the Model 888TT must be performed by Shure Brothers Incorporated, or by an FAA Approved Service Facility.

MOUNTING

The 888TT is equipped with a rear-case hang-up loop and a hang-up button for use with a mounting bracket on associated equipment.

Heavy-duty chrome-plated mounting brackets are avail- able in quantities of three as Shure Part No. RK6MB.

CABLE

To attach the cable to the 888TT, insert the modular tele- phone-type plug in the microphone jack until it locks. To re- move the cable from the microphone, insert the small screwdriver supplied with the 888TT in case hole ªAº just above the cable jack (see Figure 4) to unlock the plug and withdraw the plug from the jack.