[Boatanchors] SX-25 Troubleshooting Help Needed

[Joe Connor]

I picked up a beat-up SX-25 today and need some help.
 
After changing the 'lytics, the broadcast band (Band 1) plays beautifully. The set, however, is completely dead on all other bands. There isn't even static. There is no sound when I disconnect or conntect the antenna. Jiggling the bandswitch does not help. I have plate and screen voltages on both the 1st and 2nd RF tubes (6SK7s). 
 
I did signal injection. On Band 2, I got an RF signal from a signal generator through the 2nd RF with some amplification. (Thanks God for tube extenders!). I got an RF signal through the 1st RF with no amplification. Even the amplification I got on the 2nd RF was far less I got on Band 1 (BCB). On Band 3, I couldn't get any signal through either RF stage. 
 
The set is pretty original. There are signs of a few caps being replaced in the '40s or '50s. The only modern cap is one orange drop used as a bypass cap. I'd like to troubleshooting this systematically, rather than simply blindly replace caps and hope I hit the problem.
 
Any ideas or troubleshooting tips?
 
As always, thank you for your help.
 
 
                           Joe Connor