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Re: big coil history

Original poster: "Mike" <induction@xxxxxxxxxxx>

Interesting. Maybe it came from Phase delay lines such as used in Ham and Broadcast directional systems, or even that for a long time, the Harmonic filters for 6, 2, meters was strip line with a tuning cap and link couples on both sides of the tuned line. Even the amps for these bands, such as 450 MHz used strip line, physically shortened by cap end loading. Kind of makes me want to grab a pair of 4cx250"s and do another one up!
I don't know about the new bunch entering ham radio these days but way back we all knew the velocity factors for the common coax and open wire feed lines.
In the early days, most broadcast or RF engineers were also hams and I would imagine many coilers in the mix.
----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Thursday, March 31, 2005 3:08 PM
Subject: Re: big coil history


Original poster: Ed Phillips <evp@xxxxxxxxxxx>

"Given that folks in the 30s and 40s were using the lumped LC analysis
approach (and it had certainly been around before that), it would be
interesting to see where, when, and why, the 1/4 wavelength of wire idea
started to be used."

Probably through misinterpretation of something Tesla said?

Ed