[NewCandle] Ron Stiffler thread

[Keith Nagel]

Hi Ron,

Thanks for the update.  

In the interest of helping you and others with the RF transformer
part of the circuit, do have a look at this paper by the
famous Ben Tongue.

http://www.bentongue.com/xtalset/29MxQFL/29MxQFL.html

This paper describes in great detail how to maximize the
Q and freq. performance of ferrite cores like what you
have been using in your experiments. Probably the best
advice I can give you for an immediate improvement
is to re-anneal the cores. Depending on the core material
you may be able to do this in an ordinary toaster oven.
I have heat treating furnaces that I use for this purpose. 
Even new cores from the manufacturer can really benefit
from this. When you buy a core from places like CWS Bytemark,
they leave that last bit up to you ( or not, most amateur
radio hams just want to build the radio and don't care
about efficiency ). Also, watch out for old cores as
they can be cracked and suffer substantial degradation
in performance. 

I agree with you that based on the observations you report a
heat exchange type calorimeter is called for. Back in the late
80's when I was doing CF type work I started with the type
of calorimeter you describe and had some of the same problems.
It was particularly difficult because the electrolytic/plating
reactions are so temp. sensitive, and allowing the temp to
rise made what was supposed to be a static system a dynamic
one producing overshoot and the like.

Do keep us posted as your work progresses. 

K.