[Elecraft] Common mode chokes

[Don Wilhelm]

Bret,

Refer to the K9YC (Jim Brown) paper on RFI, Ferrites, Baluns and Audio 
Interfacing for "good" baluns.
http://www.audiosystemsgroup.com/RFI-Ham.pdf.
For common mode chokes (baluns), look particularly at Chapter 7 of that 
document.

A stack of 5 FT240-31 cores and a length of coax sufficient to wind 5 to 
7 turns through the cores is generally less expensive (and more 
effective) than the cost of commercial baluns or "in-line isolators".

73,
Don W3FPR


On 8/9/2016 5:10 PM, MaverickNH wrote:
> Further (apologies, I should have thunk it through before posting):
>
> Based on http://www.karinya.net/g3txq/chokes/ which may or may not be
> well-accepted, which choke configuration would you choose for "Best"? I'm
> actually fond of two chokes in series to address the 1.8-30MHz range, but am
> still pondering which two? At a hefty pre-made price, one can have 160-40m &
> 40-10m
> http://palomar-engineers.com/antenna-products/1-1-balun-kits/super-choker,
> albeit with no transparency of composition. What cost of of Low SNR?
> Thousands$$$ spent on Transceivers/Antennas and $100s on chokes?
>
>