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Coax Question?

Dave12

Well Known Member
I am wondering if RG58 C/U can be used as a substitute for RG148 B for the connection of a VOR/LOC/GS antenna? The radio is a Garmin SL30. Thanks in advance.
 
Rg 58 has a 50 ohm impedance, while rg 148 has 72 ohm impedance. It may work but it is not an optimal match.
 
I am wondering if RG58 C/U can be used as a substitute for RG148 B for the connection of a VOR/LOC/GS antenna? The radio is a Garmin SL30. Thanks in advance.

Dave I may have some, check the hanger when your @ KPTW this Sat
 
I think you mean RG 142 which is 50 ohm. RG58 is a lower quality coax but at VOR freqs not much difference in loss. However that is not the only consideration. The lower quality means less dense shielding which can result in noise getting into the signal.
There are lots of variations in RG58 quality also.

RG 142 also meets current flammability standards, RG 58 does not.

That said, RG58 has been used for VOR antennas for years.

Dan
 
For what it's worth I used RG58U on the VOR for a home built and it was never an issue. If you're flying VFR I would use the cheaper option. If you are flying IFR don't experiment.
 
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