Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!ptsfa!dmt From: dmt@ptsfa.UUCP Newsgroups: sci.electronics Subject: vari-loopstick Message-ID: <3220@ptsfa.UUCP> Date: Thu, 9-Jul-87 18:56:39 EDT Article-I.D.: ptsfa.3220 Posted: Thu Jul 9 18:56:39 1987 Date-Received: Sun, 12-Jul-87 02:36:26 EDT Organization: Pacific * Bell, San Ramon, CA Lines: 43 A few weeks ago someone requested information about a vari-loopstick needed for a home-built transmitter. The schematic specified a Lafayette Radio part number. I let the article expire and don't know the name of the person who asked for the information so I must ask the indulgence of the rest of you. Sorry. Vari-loopstick antennas were popular in the 1950's for small "pocket-sized" radios. I built my first one in a plastic pie container using a Popular Electronics article from late 1954. As the name implies, a vari-loopstick is a variable inductance loopstick antenna. They usually have fairly high inductance and most were tapped at the 600 ohm point. Lafayette Radio stopped advertising in Radio Electronics in Sept 1976 and in Popular Electronics in Nov 1976 so I assume that they have gone out of business. They closed their store in downtown San Francisco about the same time. The last address I have for them is: Lafayette Radio Electronics 111 Jericho Turnpike Syosset, L. I. NY 11791 J. W. Miller still sells Sub Miniature Antenna Loops in two inductance ranges: Part No. Inductance 2002 40 - 300 uH 2007 150 - 1000 uH They cost about $13.00 each. Both are tapped but the catalog doesn't say what the tap impedance is. These things are hard to find but any good electronics parts store that carries Miller coils should be able to order them. Oh, the size is about 1/2 inch diameter by 2 1/5 inches long. They are slug tuned using a brass screw and mount in a 1/4 inch hole. I hope this helps. -- Dave Turner 415/542-1299 {ihnp4,lll-crg,qantel,pyramid}!ptsfa!dmt