08-15-2018, 05:21 PM
Found elsewhere on the Internet...I do not vouch for the veracity. 
Mike's (morzh) restoration thread is here:
http://philcoradio.com/phorum/showthread.php?tid=16902

Quote:According to Sams there are only two changes between code 121 and 122. Code 121 uses a 3pF cap between pins 5/6 of 14AF7, and R5 is changed to 470K.
All other components remain the same.
Mike's (morzh) restoration thread is here:
http://philcoradio.com/phorum/showthread.php?tid=16902