Easy "B" Battery!
Rod's Classic & Antique Radios
http://www.tri.net/radio
First of all, the following project deals with voltages of 90 Volts, as described. If you are unsure of your abilities to handle this kind of project, DO NOT PROCEED! Get help, or refer the project to a qualified person. The author presents this document as an alternative to other, equally dangerous power sources, that are difficult or impossible to obtain. He further accepts no responsibility for the user. In other words, Build this project at your own risk!
Get a "Tribe-Pack" of 9V transistor batteries. (For a 90V set, you will need ten.) Then start snapping them together as in the picture above. Align the two batteries, top to top, and align the positive terminal on one to the negative terminal on the other. At this point the batteries will be offset by 1/2. Push them together, and the snap connectors do the rest! Keep this up, until you have the desired number of batteries snapped together in a series string.
You can then tape them together, as they are quite floppy. Feel free to use "The Handyman's Secret Weapon, Duct Tape", if no one's looking!
You can either capture the wires between the snaps, or "tack solder" them to the outside of the terminals. In the picture, I have tapped at the fifth battery for 45V, a common voltage requirement on TRF's.
Use an appropriate Dry Cell, lantern, motorcycle, or car battery for the "A" source, and you are ready to go! This "B" battery has a very good life, much better than what they used in the good ol' days! I have run a Freshman Masterpiece for three solid days at a show, before noticing any degradation. If you plan on this kind of use, however, use a 6V car battery for the "A", as the other types will not last that long.
Good Luck, & let me know how it works for you!
Rod Rogers
