[Hallicrafters] S-40a dissasembly

[W4AWM at aol.com]

Hi,

I haven't been into my S-40A in some years but it is definately not necessary 
to remove any knobs or the front panel. There are 2 screws on each side of 
the front panel lip and 3 more underneath. Also, there will be some towards the 
rear of the cabinet ans possibly on the back. I forget and really can't get to 
mine to look at it, but it may be possible to remove the bottom cover without 
removing the receiver from the cabinet.  A quick look will confirm this.

Go very carefully cleaning the bandswitch.  Use a Q-tip or better yet a tape 
head cleaner with a small amount of De-Ox-It or other cleaner on it. Work 
slowly and carefully and be careful not to apply too mych pressure or otherwise 
distort the switcj contacts. Never spray cleaner directly on the band switch 
wafers. Some cleaners will cause the wafers to distort and then you are in a real 
mess.

Another trick is to pull the tubes one by one and apply cleaner to the pins. 
You can carefully squirt some cleaner directly into the socket holes but just 
a tiny squirt.

Recapping is not too much trouble but work with one lead at a time and be 
sure you get the polarity correct.  Resistors have been known to change value in 
these old receivers, so if you have any problems, be sure to check them, too. 
There is usually no outward indication that a resistor has changed value 
unless it is burned or discolored. Those should be replaced without question upon 
inspection.

Good luck and welcome to the world of restoration.

John,  W4AWM