[Amps] Wire

[Jim Brown]

On Mon, 28 Jul 2008 13:37:27 -0400, Harold Mandel wrote:

>Then why do chokes burn up?

Because they are badly designed, and thus don't sufficiently limit 
the common mode current!  

>For instance, the RF Store has a pretty comprehensive
>selection of current baluns 

Do any of them specify their common mode impedance vs. frequency?

>and voltage baluns. 

Voltage baluns are TRANSFORMERS, not chokes. Transformers cause 
the core to carry the entire transmitter power. Any loss in the 
core burns transmitter power.  

>They make pretty sure that each and every advertising
>page and individual model ads say something about the 
>SSB - vs - RTTY ratings, and explain further that the
>chokes heat up.

See the tutorial discussion, choke designs, and measured impedance 
data for those chokes in 

http://audiosystemsgroup.com/RFI-Ham.pdf

You can build a FAR better common mode choke than you can buy. 

73,

Jim K9YC