[EdHolland]

Well, I am still confounded. Band C (5-18 MHz) is still really deaf. Sometimes it seems to crackle in briefly, but fades away again. Here is what I have done:

Band switch cleaned thoroughly, and connections verified for the band positions. Seemingly no problems here.
This band is the only one that does not respond to connection of an antenna wire. Medium wave and SW1 (A and B) both show an increase in signal when a temporary antenna is connected. Band C/SW2 gets a crackle, but no increase in signal. All oscillator sections are working

Here is where it gets confusing. The antenna coil for band C seems to be intact, and the band switch connects it in when the switch is in C position. But adding the temporary antenna to the antenna terminal, or the appropriate lug on the coil does not result in an increase in received signal. However, if I slip a temporary coil over the windings, connect one end to the chassis and the other to an antenna, then the set begins to recieve properly.

The detective work continues...