Letters

“After reading the 1988 newsletters, I'm very much impressed with what I see. I'm only sorry I didn't know about TCBA years ago...Thanks for the speedy service and for accepting me into your fine group.” (L.F. Jerale)

“I have a suggestion for those who are trying to produce ball lightning by suddenly varying the resonant frequency of a coil. First, design a resonant circuit with a small tuning inductor with around 5 turns on a hollow air core (PVC pipe). Second, design a system that will allow you to move an iron core freely wihin the existing hollow core and to allow the possibility of motorizing the iron core. Moving the core within the inductor will vary the inductance, thus changing the total inductance of the circuit. As a result of this change of inductance, the resonant frequency will be altered accordingly. I hope that this idea will be useful.” (Brian Dunn)

“I really enjoy reading my copy of TCBA NEWS. I only wish you had the time and patience to put them out every month.” (Dennis V. O'Day)

“Guess who invented the ignition system used in the present day automobile? N. Tesla would have gained you high marks had you been a contestant on JEOPARDY. Our host gazed furtively into space for a moment and allowed the answer. Are we ready for a Charles Kettering Society news letter?” (R.G. Kent)

“In TCBA Volume 7, #3, mention was made of a plasma globe circuit that appeared in the March issue of Radio Electronics. There exists a serious and potentially lethal design fault. Mr. Iannini directly rectifies the incoming line current. Any component failure will create a ground fault condition leading to possible electrocution! I would advise anyone wishing to build or use this circuit to operate it connected to an approved isolation transformer. The hazards are identical to that of TV sets with hot electrical chassis.

“In Volume 7, #3, there was mentioned an article on a D.C. powered coil by Charles Rakes that appeared in the October issue of HANDS ON ELECTRONICS. Mr. Rakes presents a nicely constructed coil but only can obtain discharges of only 2" or so from the 24" secondary! It is interesting to trace this back to the 1934 Tesla coil plans from POPULAR SCIENCE (can't remember the month) that also used a Ford spark coil. It would be interesting to redesign Mr. Rakes primary/secondary to a smaller size, and add a more effective spark gap. With today's high performance ignition coils, 3-4" of output could be realistically achieved.” (Brent Turner)

“A unique publication.” (William Schultz)

“Please keep up the great work. I enjoy the newsletter very much especially the technical articles and project reports from members.” (Hugh Holley)

New Members*

Corrections/Changes

* As of November 1, 1988