[Ron Ramirez]

The 1940 loop antenna will not work in a 1941 Philco. The design and construction is completely different. If you want your radio to work correctly you have to use the antenna designed for it.

Henry, you have an alternative...you can construct a smaller (narrower) loop, about the same size as the "muffler" you want. Then you can rotate it more. You'll have to readjust the antenna trimmers in the radio once done, but that should be it. Use four turns of heavy gauge wire, tapped at two turns. Keep the turns insulated from each other. Copper wire is much softer than the alloy originally used in these loops, by the way.

You could use insulated, solid wire if you don't care about originality; a narrower loop as I described won't be "original" anyway. Just come up with some sort of frame that will hold the wire in place, and fit into the holes above and below so that you can easily install and rotate your new, narrow loop.

Paul Pinyot's website shows the internal construction of a 40-190 "muffler" antenna. Looking at it, you will see how different it is from the 1941 loop.

http://www.ppinyot.com/zenith/rotating_antenna.htm
Glenn - there are desktop loop antennas, amplified antennas, etc., out there on the market; but I don't believe you can improve upon a good outdoor longwire for best reception.