During the 1980’s Rockwell was building the B-1 Bomber at it’s facility at Tulsa’s International Airport. I was fortunate to be invited to buy surplus aluminum plate there as only Oklahoma manufacturing companies could participate. And since I was manager of Hormel in Oklahoma I was in. And buy I did! All thicknesses and sizes I could. Most even have “B-1” stensiled on them….very cool indeed and a great piece of history.
The aluminum parts of this radio are from the B-1 production and hence the name. It is an extremely tough material and almost impossible to bend. I had to heat it with an acetylene torch almost to the melting point before it would give at all. The overall shape of the radio is art deco inspired and aluminum really supports the theme. The top and end, the dial pointer, the speaker cover and the skirts on the large knobs are all B-1 Bomber aluminum. The front panel and knobs are tiger maple taken from my guitar building supplies. One of the more difficult aspects of this build was making the maple panel perfectly match the contours of the aluminum plate. Techniques used in guitar making certainly came in handy with this.
The circuit is one of Dave Schmarder’s crystal schematics although this one has the addition of a little amplifier and speaker so listening is as easy as this set is to look at. I forgot all about the coil for the radio until actually wiring the set and had to scramble to come up with one that would fit into the space left over. I wound the Honeycomb coil with one of my new winding guides with stainless steel pins so that I can monitor inductance as I wind. This one was wound thinner than most using 180/44 Litz wire to 241uH and tapped it at 80% for the detecting diode. Dave tells me this is to reduce loading the tank down so much which has many benefits.
It is a double tuned radio with the antenna and main tuning being handled by matching 365pf variable capacitors. Since the main tuning shaft is horizontal and the tuning dial shaft is vertical and off set special bevel gears, pulleys and belts had to be made. Steel drill stock was polished for both of the shafts with the dial shaft being nestled in a brass bearing on the base of the set. The dial itself is a 1938 Faribanks-Morse I found displayed online and printed off. The convex glass crystal used to house it is 2 7/8” diameter and I machined a bezel for it using tiger maple. Tiny 080 brass machine bolts and hex nuts were used to secure the bezel to the top. And as mentioned, the pointer is of bomber aluminum.
The aluminum skirts on the tuning knobs were sanded down to 2,000 grit and then sprayed with cherry red tinted lacquer. The tiger maple parts of the set were also tinted with this same lacquer. Then the entire radio was finished with several coats of clear nitro cellulose lacquer.
Performance is just probably the best of any I’ve built edging out the Green Felt set before this. It is such a joy to be able to listen to these things without headphones and to be able to work as I listen. Hearing baseball broadcasts at night is most enchanting…you can almost see the bugs flying in the floodlights!