[TowerTalk] New tool - toroidal ferrite core inductor calculator

[Lux, Jim]

On 6/16/21 11:01 AM, Jim Brown wrote:
>
> All that data went into a spreadsheet, with data points at limits of 
> 160, 80, and 40M bands, centered in 20 and 15, and at around 28.5 MHz, 
> and for each winding (turns, winding material), worst case of Rs 
> (lowest value) was used to develop the Cookbook. The result is that a 
> ham using the Cookbook will have a choke that is equal to or BETTER 
> than those minimum values. 



Out of curiosity, what was the spread in apparent parameters?

good point that other materials will wind up with pickier designs less 
tolerant of parameters.


The whole "sensitivity to variations" is something that I think modern 
tools make easier to analyze - and should get more play in places like 
the ARRL handbook and antenna book.  It's one thing for a dipole, which 
is a "wide tolerance" device, but Yagis or physically small, high Q 
systems some appreciation of sensitivity is important.   A design that 
works great at one frequency, but dies 10 kHz away, or which has 
performance that falls apart if the element is 5 degrees skewed, is 
something you need to know about.