®
®
Some formulae
l
l
Resistance R of a conductor: R = ρ
[Ω]
Where: ρ = conductor resistivity
l = conductor length
A
A = conductor cross-section
138
D
l
Impedance of coaxial line:
Z =
log [Ω]
d
ε = dielectric constant
r
√ε
r
D = dielectric outer diameter
d = center conductor outer diameter
U1
l
Signal attenuation: Attenuation = 20 log
[dB]
U = input signal voltage
U12 = output signal voltage
U2
Conversion of some units:
millimeters into inches:
1 mm = 0.0394 in
inches into millimeters:
1 in = 25.4 mm
1 cm = 0.0328 ft
1 ft = 30.48 cm
centimeters into feet:
feet (12 in) into centimeters:
square centimeters into square inches:
square inches into square centimeters:
bar into pounds per square inch:
bar into Pascal:
2
1 cm = 0.155 sq in
2
1 sq in = 6.4516 cm
1 bar = 14.51 psi
5
1 bar = 10 Pa
l
°C into °F:
°F = °C 1.8 + 32
l
l
newtonmeter (Nm) into inch pound (in lb)
1 Nm = 8.85 in lb
-1
-1
-1
-1
l
l
l
l
l
l
l
l
mbar l s into Torr l s
1 mbar l s = 1.33 Torr l s
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