MN-446A Noise Meter

Product Description

MN-446A Noise Meter

The MN-446A is a high sensitivity voltmeter specially adapted for noise and signal level measurements in the audio to supersonic frequency range. A prominent advantage is the ability to be operated by remote control.
Measurements cover the frequency range modes of indication are included, namely, quasi-peak to meet DIN and CCIR standards, and the average and effective values for conventional measurements.
Five weighting filters are provided for measurements of noise and signal-to-noise ratios under conditions for DIN, IEC and CCIR requirements. The 10μV full scale range permits measurements of very low level noise in sound recording/reproducing equipment. Relative measurements of levels are made possible with the adjustable gain function.
Further, a back-up function is provided so that when the power for the production line is switched on, it is not necessary to reset the measuring conditions.

FEATURES

• Five weighting filters included: DIN/AUDIO, DIN/NOISE, IEC, CCIR/ARM
• Indication modes in accordance with – At QUASI-PEAK, AVER, and R.M.S.
• Continuously adjustable gain control provided for 0 to approximately, -10dB range.
• Usable as a wideband high gain amplifier (approx. 100dB at maximum sensitivity) with AC and DC outputs
• Weighting filter at the CCIR/ARM setting enables testing of circuits, which include the Dolby noise reduction system

SPECIFICATIONS

Input Frequency Range

10Hz to 500kHz without weighting filters

 

Voltmeter Range
Voltmeter Range	10µV to 300V, full scale, 16 range in 1, 3, 10 sequence
	-100dB to +50dB, full scale (0dB=1Vrms) and -98 to +52dBm,full scale (0dBm=0.775Vrms)

 

Accuracy
AVER.	±3% of full scale, except 10µV range.
QUASI-PEAK，R.M.S.	±5% of full scale, except 10µV and 30µV ranges. (Note: Not applicable at above 100V or 42dBm, or when using a weighting filter.)

 

Frequency Characteristic
AVER
• 10µV range	±5% : 20Hz to 20kHz ±7% : 10Hz to 30kHz ±15% : 30kHz to 50kHz
• 30µV & 100µV range	±5% : 20Hz to 100kHz ±7% : 10Hz to 200kHz ±15% : 200kHz to 300kHz
• Above 300µV range	±3% : 20Hz to 200kHz ±7% : 10Hz to 500kHz
At QUASI-PEAK and R.M.S.
• 10µV range	±10% : 20Hz to 20kHz ±15% : 10Hz to 30kHz
• Above 30µV range	±10% : 10Hz to 50kHz

 

Indication and Scales
a) QUASI-PEAK	For the quasi-peak value referred to the effective value of a sinusoidal voltage in accordance with DIN 45405 (1967), DIN 45405 (1978), CCIR (468-1) and CCIR (468-2).
b) Average	Average value referred to the effective value of a sinusoidal voltage.
c) R.M.S.	Effective value referred to the effective value of a sinusoidal voltage. (Waveform factor<2).
[Note]	When the CCIR/ARM weighting filter is used, the Average value is indicated regardless of the INDICATION switch setting.

 

Weighing Filters
a) DIN/AUDIO	Conforms to DIN 45405 (1967) for audio, 10Hz to 20kHz, measurements.
b) DIN/NOISE	Conforms to DIN 45405 (1967) for noise voltage measurements.
c ) IEC	For noise voltage measurements in conformance with the following:JIS C1502A, JIS C5551A, IHF-A-202, IEC 179-A and NAB.
d) CCIR	For noise voltage measurements in conformance with the following (ref. 0dB at 1kHz):CCIR (468-1), CCIR (468-2) and DIN 45405 (1978).
e) CCIR/ARM	Conforms to the Dolby System noise voltage measurements (ref. 0dB at 2kHz).
Optional filters	On order, any or all special types given below can be installed in place of the standard types: (1) Band pass: 1kHz, 36dB (2) Band pass: 1kHz, 60dB (3) Band pass: 400Hz, 60dB (4) IHF/T-200

 

Adjustable Sensitivity Range

0 to over -10dB

 

Input Impedance

1MΩ, approx. 30pF in shunt; unbalanced.

 

Maximum Input Voltage
AC	10Vrms, DC: 450V, in 10µV to 30mV/range.
DC	330Vrms, DC+AC peak, above 100mV range.

 

Output Voltage(At meter full scale and at open circuit)
AC	1Vrms ±10%
DC	1V ±10%

 

Output Frequency Response
AC	10Hz to 500kHz ±5% into 600Ω termination.
DC	10Hz to 500kHz ±5%.

 

Output Impedance
AC	Approx. 600Ω, unbalanced.
DC	Approx. 1kΩ, unbalanced.

 

Residual Noise
AVER. & R.M.S.	10µV Range : < 1.5µV 30µV Range : < 3.0µV
QUASI-PEAK	10µV Range : <2.0µV 30µV Range : <4.0µV

 

Remote Control
METHOD	Parallel method, positive logic, C-MOS level; with photo-isolator INDICATION 2-bit (common channel). WEIGHTING 3-bit (common channel). RANGE Switching 4-bit +4-bit (separate channels).

 

General
Power Requirements	AC 100V, 115V, 215V or 230V ±10% (Voltage selector provided), 50/60Hz; approx. 40VA.
Dimensions	Approx. 150 (W)×225 (H)×315 (D) mm
Weight	Approx. 5kg
Accessories	Input cable : 1ea.

 

*	Specifications are subject to change without notice.