Here's a recap of what the radio and I are doing:
Normal configuration on left. Configuration on right bypasses 1st RF stage.
Normal configuration, lid on, ANT post to
indoor antenna:
No audible signal at max volume.
Normal configuration, lid on, ANT post to
earth ground:
Receive 3 stations, some audio at zero volume, otherwise normal volume control.
Bypass 1st AF stage, lid on, ANT post to
indoor antenna:
No audible signal at max volume.
Bypass configuration, lid on, ANT post to
earth ground:
Receive 7 good stations and 3 weak stations with normal volume control. Only the strongest station gives some audio at zero volume.
(I pulled out the 1st RF transformer and it appears to be OK, with 2.2 to 2.4 ohms through each winding.)