GENERAL RADIO KNOB AND INDEX

     It showed up ay a popular auction site: a genuine GR calibrated knob:

     In the original box (love those fonts!):

      With an "index:"

     Actually, three of them, and that's the part you never see.  Sure, it's just (just?) a line scribed on a piece of metal, the same nickel-plated brass as the calibrated skirt, but it's mounted on a little leaf spring and shaped to ride right on the edge of the calibrations. It beats the usual crude expedients by a long ways.

     There's one fancier replacement, a vernier scale that allows reading the dial to a tenth of a division.  Either one is a nice thing to have when the urge to build some interesting device happens to strike.

INDIANA STATE FAIR RETROTECH

     The Pioneer Village area of the Indiana State Fair is a hotbed of retrotech and, as it turned out, a few vendors thereof as well.  I passed up a well-worn set of radio headphones, 1920s or '30s vintage, but these small items caught my attention and had to come home:

        The pens, by the Bridgeport Pen Co. of the Connecticut town of the same name, are an unusual design, sized for sign or poster work and intended to be used with India-type drawing ink.  The narrowest one is turned so you can see the corrugated brass ink retainer.  They show up fairly often.

     The pencil saver is a clever gadget dating back to Victorian times, allowing you to use a pencil right down to the stub -- and in the stored position, it keeps the point out of harm's way.  This one is a bit newer, 1930s perhaps, with a well-petrified eraser. There's a little drawing of a cave entrance on the label, with the legend, "Souvenir of Mark Twain Cave, Hannibal, Mo."  The entrance still looked the same in a 1956 photograph and may not be much changed even today.

     The trammel (or "beam compass"), made by Feranco Products (Ferance Construction Co. of Penfield, N.Y.) is a very small example; large trammel points that clamp on a framing square or yardstick are more commonly seen.  Neither ZIP nor Zone code on the address and the points proper look to be zamak -- 1930s though 1950s?  This one easily scribes circles up to 12 inches in diameter.  The previous owner left the lead properly sharpened, too. There's a set of actual scribe points (the other end has a stepped drafting type), extra lead and spare clamp screws along with their G U A R A N T E E.  It may have originally contained more beams, which the clamp screws would have held together for making larger circles.

     Prices?  Including tax, I paid more for lunch (a ribeye sandwich and a glass of pop) than I did for any of it -- $10  total for the three pens, the same for the beam compass, $4 for the pencil saver.  This compares rather favorably with asking prices online and these are useful items.