TB 9-6695-300-50
(5) Provide the owner/user a test report stating the tuning fork frequency. If the
RADAR frequency is known, calculate tuning fork frequency in MPH and include in test
report.
NOTE
If the RADAR frequency is known, the tuning fork frequency in
MPH can be calculated using the standard Doppler formula:
V = C x fd
2 x ft
Where:
V = Tuning fork frequency in MPH
fd = Tuning fork frequency in (Hz)
C = Speed of light (MPH x 10 +9 )
V =0.6706 x fd
2 x ft
Example 1: For X-band RADARS:
V =0.6706 x 1883
2 x (10.525)
V = 60 MPH
Example 2: For K-band RADARS:
V=0.6706 x 4322
2 x (24.15)
V=60 MPH
Example 3: For Ka-Bands RADARS:
V=0.6706 x 6209
2 x (34.7)
= 60 MPH
NOTE
Simpler formulas for calculating tuning fork frequencies other
than those listed in table 1 can be used as follows:
X-Band
TFHz = V(31.389)
K-Band
TFHz = V(72.023)
Ka-Band
TFHz = V(103.48324)
Where:
TFHz = Tuning Fork Hz
V = MPH
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