Shure FP42 manual Specifications, Accessories, Telephone interconnection

is recommended for normal use to provide approximately 14 dB of headroom from operating level to clipping level.

The VU meters are illuminated by a single cartridge-type, 6.3V in- candescent lamp, operating well under its normal rating for a life ex- pectancy of greater than 10,000 hours. The lamp is only lit for ac operation. Consequently, the illumination serves as a visual alarm if the ac is interrupted and the unit has switched to battery operation.

The VU meters are connected on the primary side of the output transformer to assure protection from any dc level on a telephone line.

Telephone interconnection

When using the FP42 connected directly to a telephone line, check to see whether the telephone company requires an interface cou- pler between the FP42 and the telephone line. If a coupler is re- quired, make certain the coupler selected and the wiring arrange- ment are in compliance with local telephone company regulations. Connect the telephone line to the left or right Output connector and turn the Pan controls so that the entire output signal is on the tele- phone-connected output, or switch to mono operation.

Telephone Line Surge Protection

When using the FP42 connected directly to a telephone line subject to lightning-induced voltage surges, the following part (commer- cially available) can be installed across the output terminals to pro- vide additional protection for output circuit components: Metal Ox- ide Varistor, General Electric Co., Type No. V22ZA1.

SPECIFICATIONS

Frequency Response (ref 1 kHz) 30 to 20,000 Hz, +1, –3 dB

Voltage Gain (at 1 kHz)

INPUT			OUTPUT
	LINE	MICROPHONE	MIX BUS	PHONES	PHONES (CUE)
Mic	90 dB	40 dB	25 dB	100 dB	85 dB
Line	40 dB	–10 dB	–25 dB	50 dB	35 dB
Mix Bus	55 dB	5 dB	–	62 dB	–

Inputs

INPUT	IMPEDANCE (at 1 kHz)		INPUT CLIPPING LEVEL
	FOR USE WITH	ACTUAL	(at 1 kHz)
Mic	19–600 ohms	1k	–40 to –5 dBV*
Line	Less than 10k	66k	+10 to +45 dBV*
Mix Bus	3.5k	3.5k	0 dBV
*Dependent on input control setting.

Outputs

OUTPUT	IMPEDANCE (at 1 kHz)		OUTPUT CLIPPING LEVEL
	FOR USE WITH	ACTUAL	(at 1 kHz)
Mic	150 ohms	<1 ohm	–33 dBV min. across150
			ohms
Line	600 ohms	185 ohms	+18 dBm min. across 600
			ohms
Mix Bus	3.5k	3.5k	–15 dBV min. across 3.5k
Headphones	8–2000 ohms	100 ohms	+6 dBV min. across 200 ohms

Noise

Equivalent Input Noise: –129 dBV (low-impedance micro- phone, 150 ohms, 300 to 20,000 Hz) into 600-ohm load at full gain

Equivalent Input Hum and Noise: –127 dBV (low-impedance microphone, 150 ohms, 20 to 20,000 Hz) into 600-ohm load at full gain

Output Noise: –70 dBV maximum (output control full counter- clockwise [off]), –55 dBV maximum (output control full clockwise [on]) (input control down, 300 to 20,000 Hz)

Output Hum and Noise: –62 dBV maximum (output control down), – 53 dBV max. (output control up, input control down, 20 to 20,000 Hz)

Distortion

0.4% or less THD, 30 to 20,000 Hz at + 15 dBm output; 0.5% or less IM distortion at +15 dBm output into 600 ohms

Common Mode Rejection

65 dB minimum with input of – 20 dBV at 100 Hz

Control Interaction

Less than 1 dB with any control combination

Overload and Shorting Protection

Shorting outputs, even for prolonged periods, will cause no dam- age; microphone input will not be damaged by signals up to 3V

Separation (left and right outputs)

40 dB minimum at 10 kHz; 50 dB minimum at 1 kHz

Low-Cut Filters

6 dB per octave rolloff at 150 Hz

Limiter

Threshold: Adjustable, +8 to +14 dBm

Attack Time: 3 msec typical

Recovery Time: 500 msec typical

Peak/Limiter Indicators

Limiter out: lights 6 dB below clipping

Limiter in: lights at onset of limiter action

Phase

All outputs in phase with all inputs. Pin 2 is “high” with respect to pin 3; pin 1 is ground. Tip of mix bus jack in phase with pin 3. Tip and ring of headphone jacks in phase with pin 2 of left and right outputs, respectively.

Tone Oscillator

1 kHz; +18 dBm maximum at both outputs with Master level full up

Phantom Power

30 Vdc nominal, 3.3k series resistance, automatically disabled with input switch in Line position

Operating Voltage

Ac Operation: 120 or 240 Vac ±10% (internally selectable), 50/60 Hz, 6W

Dc Operation: 27 Vdc nominal at 30 mA typical no-signal, 32 mA typical at 0 VU (+4 dBm) output; 21.5 Vdc minimum; battery life approximately 10 hours with alkaline batteries at +4 dBm output in continuous use; three 9-volt batteries, type NEDA 1604A

Temperature Range

Operating: –18°to 57° C (0° to 135° F)

Storage: –29°to 71° C (–20°to 160° F)

Dimensions

79.5mm H x 310 mm W x 230 mm D (3–1/8 in. x 12–7/32 in. x 9–1/16 in.)

Weight

Net: 2.95 kg (6 lb 8 oz)

Packaged: 3.45 kg (7 lb 10 oz)

Certifications

Listed by Underwriters Laboratories, Inc.; listed by Canadian Standards Association as Certified

ACCESSORIES

The Model A16R Rack Panel Kit consists of a 19 in. x 3–1/2 in. (483 mm x 89 mm) precut rack panel and necessary hardware for rack-mounting the FP42 with its cover in place and end caps re- moved in a standard 19” (483 mm) rack panel.

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