[Boatanchors] 6146 A or B ?

[Mr. and Mrs. Magoo]

It would appear to me that the Hammarlund HX-500 is another transmitter 
which does not like 6146B tubes.  The "A" and the plain-Jane 6146 work fine 
but the rig takes off with the "B" tubes, especially if the bias mod has not 
been done.

Bill, VE3NH