NL-28声级计是日本理音*新推出的声级计，NL-28是替代原来NA-27的新产品!
Sound Level Meter1/3 octave bａnd real-time analyzer NA-28
Real Time Octaves (16 Hz to 16 kHz) or 1/3 octaves (12.5 Hz to 20 kHz)Real Time Simultaneous Octaves (16Hz to 8kHz)1/3 Octaves (12.5Hz to 12.5kHz)Data stored as text files direct to CF cardMeasureslogs eq, max, min5 percentile values (LN) in octaves and/or 1/3 octavesAuto Stores 300 000 data sets or 1 000 hours of 1 second 1/3 octaves onto 1 GB CF cardAuto Stores 1000 data sets or 10 000 of 1 second 1/3 octaves to internal memoryManual Storage for 1 000 data sets internally or 100 000 data sets to 1 GB CF cardLinearity 110 dB in Sound Level Meter Mode95 dB in Analyzer Mode16 hours battery life with 4 Alkaline"C" CellsMainSub-Channel for simultaneous selection of 2 time or frequency weightings F(Fast), S(Slow), 10 ms Time Weightings plus Peak & Impulse on Sub-ChannelData transfer using CF card or USB (meter/CF card appearing as virtual disk)Measurement can be started by internal or external triggerComparator output to trigger external devicesACDC outputs of main and/or sub-channelExpandable functionality using programme cardsIEC 61672-1:2002 Class 1，IEC 61260:1995 Class1，ANSI S1.4-1983 Type 1，ANSI S1.11-2004 Class 1Specification
| Applicable specifications | IEC 61672-1:2002 Class 1, IEC 61260:1995 Class 1, ANSI S1.4-1983 Type 1, ANSI S1.11-2004 Class 1 |
| Measurement functions | With both a sound level meter modeanalyzer mode, it is capable of simultaneous main channelsub-channel measurement in either mode. Timefrequency weighting are set separately for the mainsub-channels. |
| Measurement modes | Sound level meter mode: Measurement of all-pass values indicated in the measurement items below in the main or sub-channel, Measurement of either Lpeak or Ltm5 in the sub-channel Analyzer mode : Real-time octave1/3 octave bａnd analysisall-pass measurement in the main channel, only all-pass measurement in the sub-channel |
| Measurement items | Simultaneous measurement of all items in the selected time weightingfrequency weighting characteristics Instantaneous sound pressure level Lp, Equivalent continuous sound pressure level Leq, Sound exposure level LE, Maximum sound pressure level Lmax, APMaxBandMax can be selected as maximum, Minimum sound pressure level Lmin, Maximum 5 time ratio sound level LN (1 to 99%, 1% Step), Calculation from Lp or Leq 1sec |
| Measurement time | 1 to 59 sec, 1 to 59 min, 1 to 24 hours |
| Microphonepreamplifier | Microphone UC-59, Preamplifier NH-23 |
| Measurement range | A: 25-130dB, C: 33-130dB, Z: 38-130dB |
| Frequency Range | 10 Hz-20 kHz |
| Time weighting | Main:Fast, Slow, 10ms Sub:Fast, Slow, 10ms, Impulse |
| Display | Color semi-transparent TFT-LCD display with backlight (240 X 320 dots) |
| Power requirement | Four IEC R14P (size"C") batteries or external power supply Operating time Manganese batteries: R14PU, 6 hours Alkaline batteries: LR14, 16 hours (10 hours if backlight is continuously activated) |
| Dimensionsweight | 331 (H) X 89 (W) X 51 (D) mm , approx. 730 g (including batteries) |