Topband: CAT5 twisted pair

[Charlie Cunningham]

J

 

From: James Rodenkirch [mailto:rodenkirch_llc at msn.com] 
Sent: Monday, August 12, 2013 6:04 PM
To: Charlie Cunningham; jim at audiosystemsgroup.com; topband at contesting.com
Subject: RE: Topband: CAT5 twisted pair

 

OH...okee dokee on not needing the 2:1 xfmr 

 

> From: charlie-cunningham at nc.rr.com
> To: jim at audiosystemsgroup.com; topband at contesting.com
> Date: Mon, 12 Aug 2013 17:12:59 -0400
> Subject: Re: Topband: CAT5 twisted pair
> 
> Jim,
> 
> I completely agree with Jim Brown! I noted those 2:1 transformers the
other
> day and meant to send you a note to say that I wouldn't bother! That
> little bit of mismatch loss won't make any difference!
> 
> 73,
> Charlie, K4OTV
> 
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Jim
Brown
> Sent: Monday, August 12, 2013 5:03 PM
> To: topband at contesting.com
> Subject: Re: Topband: CAT5 twisted pair
> 
> On 8/12/2013 1:50 PM, James Rodenkirch wrote:
> > as well as a 2:1 transformer just prior to the input to the shack.
> 
> While there's nothing wrong with attempting to match the termination Z, 
> don't assume that it will do much. The input Z of the RX may not be 50 
> ohms (although the doc may say it is), a small mismatch won't contribute 
> enough loss to matter, and it does not affect noise rejection. What 
> matters is balance and twisting.
> 
> 73, Jim K9YC
> _________________
> Topband Reflector
> 
> _________________
> Topband Reflector