[Hallicrafters] S-40A Sensativity

[James R Carr]

I'll try it.
Jim
N7FCF
Shelton, WA
----- Original Message ----- 
From: "Glen Zook" <gzook at yahoo.com>
To: <hallicrafters at mailman.qth.net>; "James R Carr" <n7fcf at hctc.com>
Sent: Sunday, January 25, 2009 4:33 PM
Subject: Re: [Hallicrafters] S-40A Sensativity


> Try a single wire or else connect the braid to the center conductor of the 
> coaxial cable and then connect to the terminal that is the farthest from 
> the ground.  Connect the 2nd antenna terminal to the ground terminal.  A 
> lost of the receivers from before at least the mid 1950s do not like a low 
> impedance from coaxial cable.  They have considerably better sensitivity 
> with feedline impedance between 300 ohms and 600 ohms or with a single 
> wire.
>
> If that improves the sensitivity then you can use a TV balun connected to 
> the two antenna terminals (with the ground removed) and then use coax. 
> The article that appeared in Electric Radio a while back can be found at
>
> http://k9sth.com/uploads/TV_baluns.pdf
>
> Even if you find other problems connecting the antenna as described above 
> will help considerably.
>
> Glen, K9STH
>
> Website:  http://k9sth.com