Bruel & Kjaer 2607 Measuring Amplifier 

Low noise, high gain measuring amplifier with analogue indicator instrument.

Sensitivity from 10/A/ to 3 0 0 V f.s. adjustable in 10dB steps. RMS value indication for crest factors up to 40 with 'Fast' and 'Slow' damping of the indicator instrument and pulse measurements with index lock on the maximum peak value or the maximum RMS value reached. Interchangeable scales for voltage, dB, acceleration, sound level and other measurements. The level of 0 is visible directly on the instrument. The frequency range from 2 Hz to 2 0 0 kHz can be corrected from 22.4 Hz to 22.4 kHz by means of buttons.

Built-in filters A, B, C and D for sound level measurements. Input and output overload indicators Input sockets for standard B & K plugs for 7-pin connector and B & K microphone preamplifiers. AC and DC outputs

In addition to RMS, pulse and index lock measurements, it can measure positive and negative peak values, allowing measurements of very short signal durations; rectifier response time is 20/LIS. The drop time is adjustable from 0, 1 to 300 s, thus allowing narrow-band noise measurements. The rectifier also has slow and fast instrument damping for sound level measurements. The instrument can be switched to linear or logarithmic readout, and allows rms reading of signals with a crest value up to 5. The output has a dynamic of 60dB in RMS position, with crest factor 1.4. Dynamics 50 dB with crest factor 5 in peak position. Bandpass filter1 61 7 is ideal for use with this amplifier. Model A , B or C.

When used with the mod.1617 octave-thirds filter, it allows measurement of chaotic signals with measurement error control. The B T control is kept constant.