Re: ribbon vs. tubing

Greg wrote:

> What's the 'proximity effect'?

It's an extension of the skin effect and has to do with current 
bunching caused by the relative proximity of current carrying 
conductors. If you can get hold of it, the Philips Technical 
Publication #207 "High Frequency Transformer Winding Design"
has the best info on it I have yet seen. If you can't, send me your 
snail address and I'll be happy yo send you a copy.