Recent content by ninefingers

Yeah, you're right...but, test the ferrite at the frequency it will be used at. Efficiency/turns ratio Will vary.

This is True. But, if you deal with surplus/buy at swaps like I do, you probably won't know what core you have. I've always wanted to find a cheap source for Variac cores to wind my own high-efficiency. low-turn, extremely- light line transformers. The turns ratio is about 1.25-to-1.5 turns per...

That's hard to believe--but, then, I sold a lot of innocuous chemicals to Aussies who couldn't get them locally. It's like--are they afraid you're going to off a few 'roos or something? Blind an Emu?:gun: Maybe we should start a petition right here. I'd sign!;) On topic: I've a lot of...

The ARRL Handbook (Big edition) has , under basic electronics and antenna design, Amidon ferrite and its properties. (Look under "traps".) It shows how to wind a certain inductance toroid. Now, note that you have to Know what type of composition the ferrite Is to do this! You can also use a...

I never really "built one" . I don't consider soldering a premade laser diode to a circuit " making one". I had a red ruby rod for years (bought it in the '90's when I was 42), but it didn't have optically-polished ends. Ruby is Hard, so I never figured it out, I simply got an green...