----- Original Message -----
From: "Jim Lux" <jimlux@earthlink.net>
> In the cable TV world, they tend to use dBmV (into 75 ohms, presumably),
> but in any case losses should work the same regardless, a typical path
from
> "mainline cable" appears to be something like 26 dB for the tap, 2dB for
> the drop, 6dB for inhouse cable and splitters, so 34dB from "main wire" to
> the -40 odd at the set.(I seem to recall something like -33 dBm
corresponds
> to +15dBmV, which is a typical level). Figure at least zero, and then
> they'd add some margin, so they're probably running +10 dBm (per carrier)
> or several watts down the wire with all 100+ channels...
> Generally I think the carrier levels on analog coaxial trunks are
set at something like +33dBmV/carrier (~-15dBm).
Holy leaky coax, Batman! What the heck does that have to do with towers and HF
antenna construction projects? Please QSY to the RF engineers reflector and let
us mere mortals get back to antenna and erection topics. Thank you.
Cheers,
Steve K7LXC
TT ADMIN
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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