it seems strange that both Osterman and Dachis mention the 42 ?but ?neither ??mentions 42A; are we gathering that the IF tubes listed are for? the A version?? ?
I see the ?BAMA manual for the 42 shows 6SK7??6SG7 ?and? ?antiqueradios says the same
When I search for a 42A ,I get only 42 ,, seems that even BAMA does not have a 42A.? Somebody must have dug out the differences.