Table of Contents
Advertisement
Fig.3.6
p-Residual Intens. Idx
screen
6) Select Phase Calib. & Verify to calibrate the phase difference between the channels to a
minimum or select Verify followed by OK.
7) The phase calibration and/or the verification will now be performed. Note that the
, shown in the display, must exceed 30 seconds. (In the first 30 seconds, Type 2260-E
Time
compensates electrically for its own phase mismatch. Thereafter, the phase mismatch of the
whole system, Type 2260 and probe, is measured. When satisfied that a stable situation has
been reached (after about 1 – 2 minutes), press Stop Verify soft key.)
8) Once the Stop Verify soft key is pressed, press Save. If you wish to repeat the verification,
choose Undo to repeat the process.
3.2.2
Verification above 3 kHz
If you wish to perform a pressure-residual intensity index verification using the broadband pink
noise source at frequencies above 3 kHz, then the same procedure as described above is used.
See 3.2.1"Verification up to 3 kHz" on page 18.
✐
The maximum frequency at which verification can be made without the spacer is 6.3 kHz.
Please note:
However, it is necessary to remove the spacer that separates the two microphones of the sound
intensity probe while ensuring that the correct spacing is maintained to enable correct fitting in
the chamber and sealing of the gasket.
1) Loosen the knurled black collar on one side of the microphone/spacer assembly, to allow the
sound intensity probe to slide backwards and forwards.
2) Pull the spacer and one microphone away for the other microphone. While holding the
microphone attached to the spacer with one hand, unscrew the spacer from the microphone.
Be careful that you do not loosen or unscrew the microphone protection grid.
3) Use the spacer (Fig.3.7) to maintain the correct distance between the two microphones and
tighten the knurled black collar to hold the slider in place.
4) Insert the sound intensity probe, without the microphone spacer, into Type 4297 and perform
the verification exactly as described in "Verification up to 3 kHz" on page 18.
5) After the verification, replace the spacer between the two microphones.
Calibration Procedure with Type 2260-E Investigator™
CHAPTER 3
19
Elapsed
Advertisement
Table of Contents
