Jack's Oldest Radio Transmitter Skywriter Defiant 1941?

Today I donated Jack's (John Barnes Leddy) oldest radio transmitter to History San Jose.  This was in accord with his instructions before he died.  Here is a picture of the transmitter.  As you can see in the picture, it was a Skywriter Defiant high frequency communications receiver produced by Hallicrafters, Chicago.  The transmitter is described in this Radio-craft magazine from 1941