Hi Rich,
The cable loss of RG-58 type of coax is somewhere between 5 - 6 dB per 100
feet at 150 MHz. It could be higher if the coax is older. This is also
assuming you have an antenna that is well matched and has a low VSWR. So,
lets say for example the coax you're using has a 6 dB per 100 feet loss. if
you were to use a piece 25' long, the loss in the coax would be 1.5 dB. How
this related in real life is if you had a rig that put out 25 watts only 18
watts would actually reach the antenna. It's works the same on receiving.
You will loose 1.5 dB of received signal strength.
It's best to use a high quality coaxial cable with low losses. LMR-400 has a
loss of 1.5 dB per 100 feet at 150 MHz. A 25 foot run of LMR-400 will have a
loss of .4 dB and with 25 watts into it from your rig you will get 23 watts
to the antenna.
Hope this helps,
73,
Dave / W6TE
----- Original Message -----
From: "Rich Long" <kf6bka@yahoo.com>
To: <vhfcontesting@contesting.com>
Sent: Tuesday, August 19, 2008 11:28 AM
Subject: [VHFcontesting] Coax
> What would be the best coax to use for 2m SSB? I have RG-58 but I have
> been
> told that it's lossy on 2M SSB.
>
>
>
> Rich
>
> KF6BKA
>
> _______________________________________________
> VHFcontesting mailing list
> VHFcontesting@contesting.com
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>
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