10
LI0056 – Revision 28 May 2015
Calibration
The 67SB is calibrated in a controlled laboratory environment using traceable calibration
equipment before leaving the factory. We recommend calibration prior to use to ensure
the accuracy of your measurements. You can use any of the G.R.A.S Pistonphones
42AA and 42AP.
In-Situ Calibration
With the GR1462 External Calibration Adapter, you can calibrate the microphone in the
67SB without dismounting it. The adapter is mounted as shown in Fig. 9. An O-ring
inside the adapter ensures a proper fit over the microphone. The correction factor is
0.04 dB.
67SB Blast Probe Microphone
Serial No. XXXXXX
G.R.A.S.
Sound source
For rem
oving
probe top
For rem
oving
sensor
Dot for correct alignment
GR1462 (front view)
Top view of 67SB with GR1462
Side view of 67SB with GR1462
G.R.A.S.
Pistonphone
Type 42AP
Serial No. XXXXX
IEC 60942 (2003) LS
Signature Series
G.R.A.S.
Pistonphone
Type 42AP
Serial No. XXXXX
IEC 60942 (2003) LS
Signature Series
The pistonphone can be placed
directly onto the adapter
Pistonphone, e.g 42AP
Adapter GR1462
67SB
Fig. 9.
The 67SB blast probe with GR1462 adapter for in-situ calibration.
Fig. 10.
Pistonphone calibration of the 67SB using the adapter GR1462.