[Boatanchors] antenna question

[J. Forster]

The difference between 50 and 75 Ohms is pretty much irrelevant for
receiving HF unless you are trying to squeeze out the last droplett of
performance.

That said, there are a few things to consider:

If the system has a distribution amp it may not be any good for HF/LF.
If the system uses power splitters, they will likely not be any use.
If the system uses 75 Ohm BMCs, they will need to have the correct mate.

Essentially, the guy will be converting his setup to look like a
multicoupler serving a bunch of receivers.

-John

==========




> An acquaintance who is also a boatanchor collector/SWL/BCB DXer (and
> messes
> with longwave a little bit) asked me the following antenna question.  It
> has
> been a while since I have sharpened up on antennas so I said I would ask
> the
> wizards.
>
> Wizards:
>
> He recently moved from a plain old house to a quite new residence with
> metal
> siding.  He reports that reception has gone in the tank compared to his
> old
> place.  He has various radios scattered throughout the house and had
> previously connected only a chunk of wire to most and received a good
> quantity of signals.  He also uses several McKay/Dymek active loop
> antennas
> (one per radio) on some of the BCB radios.  None of these work well in the
> new place.  He uses a McKay/Dymek (Stoner) outdoor active antenna (DA100D)
> at his bench.  The latter works very well.  The DA100D has an amplifier at
> the outdoor antenna and another inside at the bench.  Output of the base
> unit is RG58 cable to the receiver in use.
>
> The local TV-DSL/internet provider has gone digital and recently came
> through and replaced their old system box with a new one at the entry
> point
> and ran CAT 5 cable from their new box to another "BOX" at each TV set and
> computer, abandoning his 75 ohm analog distribution system which runs all
> over the house.  The question: Is there a good way to connect the active
> antenna output which uses RG58, 50 ohm output  to utilize the 75 ohm
> system
> to get an antenna to his several radios and expect decent receiving
> performance?
>
> He came up with this as he was preparing to remove the old abandoned
> system.
> He has decided that if he can't use the 75 ohm system, "Its gotta go!"
> Frankly, he has more ambition than I as I would just let the old system
> collect spider webs.
>
> Gerry
>
>
>
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