Receiver Antenna Matching (was: Re: [Milsurplus] R-388)

[mstangelo at comcast.net]

Television "binocular" type (with two holes) balun cores are optimized for the VHF range. You can get better operation in the low HF range by using more turns through the core or winding a 4:1 balun on a "binocular' type core with a higher permability such as a type 43.

Mike N2MS

-------------- Original message -------------- 

> You need to check each transformer as i have found a couple that have 
> increased loss below 10 mhz. Otherwise i have used them for several receiver 
> inputs. 
> 
> Healthfully yours, 
> DON 
> ----- Original Message ----- 
> From: "D C *Mac* Macdonald" 
> To: 
> Sent: Tuesday, August 09, 2005 10:22 AM 
> Subject: Receiver Antenna Matching (was: Re: [Milsurplus] R-388) 
> 
> 
> > The 4:1 ratio between 200 and 50 Ohms 
> > would be the same as that of the 300 to 
> > 75 Ohm TV baluns. I would imagine that 
> > loss (if any) due to impedance mismatch