[RFI] Choke questions

[Jim Brown]

On 1/21/2020 1:52 PM, David Eckhardt wrote:
> I've found the super-flex insulated 'antenna wire' sold by Davis RF is
> pretty good for winding larger ferrite cores (bifilar, quadfilar, ...).

No advantage to this over THHN, and I suspect THHN is cheaper. Also, I 
find it important to wind 2-wire chokes with two colors to make certain 
that turns don't get twisted (bad).

> Also I've repeatedly used RG-142 Teflon coax for winding chokes.  It's high
> power silver coated 50-ohm coaxial cable about the same outer diameter as
> RG-58.

RG400 goes it one better -- it's like RG142, except that the center is 
stranded silver-coated copper. After discussions with N0AX and others, I 
settled on it for my choke designs on the basis of bend radius when 
winding on 2.4-in o.d. toroids.

Cookbook is here. http://k9yc.com/2018Cookbook.pdf

> No connection to Davis RF other than use their products.

I like Davis a lot.

73, Jim K9YC