Towertalk
[Top] [All Lists]

[TowerTalk] Fwd: Fwd: Fwd: RG-149: 50 ohm/70 ohm - does it matter?

To: towertalk@contesting.com
Subject: [TowerTalk] Fwd: Fwd: Fwd: RG-149: 50 ohm/70 ohm - does it matter?
From: Hans Hammarquist <hanslg@aol.com>
Date: Mon, 16 Dec 2013 14:47:30 -0500 (EST)
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Jim,


If I recall my radio teacher, 50 ohms were decided sometimes during WW2 or even 
earlier. There were some switch from (I may be wrong here) from 50 to 52 ohms 
at one point. As a result the "obsolete" cables became available as surplus 
(for us radio hams :).


73 de,


Hans - N2JFS


PS. I hope he grabbed that cable by now.



-----Original Message-----
From: Jim Brown <jim@audiosystemsgroup.com>
To: towertalk <towertalk@contesting.com>
Sent: Mon, Dec 16, 2013 1:45 pm
Subject: Re: [TowerTalk] Fwd: Fwd: RG-149: 50 ohm/70 ohm - does it matter?


On 12/16/2013 10:36 AM, n8de@thepoint.net wrote:
> My comment was intended to indicate that YAGI antennas can easily be 
> modified to 75 ohm feed impedance.

Yep.

IMO, 50 ohms was an arbitrary decision made by the first designers of 
solid state transceivers, whose primary experience was design for 2-way 
radio, where 50 ohm antennas were the standard. I don't see it as a bad 
choice, since the electrically  low dipoles that most hams are able to 
install are closer to 50 ohms than 75 ohms.

> Way ahead of you on wire antennas and verticals

I knew that. :) Comments were for others who are not.

73, Jim
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

 
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>