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Transmission Line Calc

iPhone App to Analyze RF Transmission Lines

Transmission Line Calc allows you to perform several calculations related to RF transmission Lines.

After selecting from one of 53 different transmission lines, you specify the length and operating frequency. The characteristic impedance and velocity factor of the cable is displayed, and the attenuation (loss) as well as electrical length (in wavelengths and degrees) is displayed.

Next, you can specify the impedance (both resistive and reactive) and whether this is measured at the input to the transmission line or the load. The impedance at the other end of the transmission line is calculated, as well as the SWR (Standing Wave Ratio) for both ends.

The loss due to the SWR is then calculated and displayed, as well as the total loss.
Next, you can enter in the input power, and the loss due to the cable as well as SWR is displayed, as well as the net power out.

53 different commonly used transmission lines are available for selection.

Belden 8215 (RG-6A)
Belden 8237 (RG-8)
Belden 9913 (RG-8)
Belden 9258 (RG-8X)
Belden 8213 (RG-11)
Belden 8261 (RG-11A)
Belden 8240 (RG-58)
Belden 9201 (RG-58)
Belden 8219 (RG-58A)
Belden 8259 (RG-58C)
Belden 8212 (RG-59)
Belden 8263 (RG-59B)
Belden 9269 (RG-62A)
Belden 83241 (RG-141A)
Belden 8216 (RG-174)
Belden 8267 (RG-213)
Davis RF Bury-Flex
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Andrew Heliax LDF5-50A
Andrew Heliax LDF6-50A
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CommScope 6 Series Plenum
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MACX350A 3-1/8" Rigid Line
MACX450A 4-1/16" Rigid Line
MACX650A 6-1/8" Rigid Line
MACX775A 7-3/16" Rigid Line
MACX850A 8-3/16" Rigid Line

Are you looking for a technology or radio related iPhone/iPad app but can't find one that does what you want? Have an idea for an app that you'd like to see? Contact us at!

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Last modified March 28, 2019