[Heathkit] SB-104 Question

[Donald Spoon]

A couple of weeks ago, I asked a question here regarding some 
differences between my SB-104 and the SB-104A manual that I have re:  
plugging in a new "E" board with a CW filter installed.  Thanks to all 
who replied.  Your comments were quite helpful.

Apparently the switch lettering differences that I noticed was a 
production change, and there was a rather large upgrade kit produced to 
"upgrade" the various models to the SB-104A.  I have discovered the 
manual for this upgrade is freely available in PDF format on the web, 
and shows all the parts and wiring changes!  It is under the name of 
"SBM-104-2".  With the assistance of this manual, you can determine how 
many of the changes have been made to your unit, which was the 
fundamental problem I had.    There is a specific section on wiring 
changes for the "E" board with the CW filter installed, including some 
chassis wiring changes on the switches.  I can now simply compare my 
unit to the modifications and see what I have to change!

I hope this info will be of use to others...

Cheers,
-Don Spoon-
K0APK