[TowerTalk] CMC-230-5K

[Jim Brown]

There's something I don't understand here. In 2007, I published the 
research upon which all of this is built, with measured data for a broad 
range of chokes for the ham bands, and with full instructions for buying 
the cores at very good prices, and a "cookbook" for the various ham 
bands. Why in hell would you want to pay someone 3x the cost of doing it 
yourself, when all you have to do to do it yourself is wind turns of 
coax through ferrite cores?

AND -- l would not trust any published power ratings for ANY chokes 
without understanding the common mode voltage that they will see in any 
given installation. To do that, you've got to put them in an NEC model 
that approximates YOUR installation. Simply putting one of these chokes 
in a sealed enclosure greatly reduces its power handling because it 
greatly reduces air flow around the choke.

73, Jim K9YC

On Tue,4/19/2016 3:30 AM, Jim Thomson wrote:
> I just received a pair of  CMC-230-5K  common mode chokes...from MyAntennas.com to experiment with.
> They are configured as a  line isolator, with  silver-teflon  SO-239s  on each side.  They can also be configured as
> a balun, with a pair of standoffs on the balanced ant side if you like.   Extremely well designed and built, better
> than I expected.