[Johnson] Invader 200 Finals ??

[Glen Zook]

NEVER mix a 6146 or 6146A/8298 with a 6146B/8298A.  They are completely different tubes and mixing them will almost always cause problems.

The 6146B/8298A can cause problems in many units that were designed for the earlier versions.  I would go with the 6146A/8298 or 6293 in your transmitter.  Remember that the 6146W tubes with a code date of the 2nd half of 1964 and later are going to be 6146B/8298A and not the 6146A/8298 equivalents of the 6146W tubes before that date.

For the article on the 6146 family of tubes that was in Electric Radio a while back, and which has been reprinted in various other publications, go to

http://k9sth.com/uploads/The_6146_Family_of_Tubes_1.pdf

Glen, K9STH

Website:  http://k9sth.com


--- On Tue, 4/14/09, Richard W. Solomon <w1ksz at earthlink.net> wrote:

Is there a version of the 6146 that is better to use in the Invader ? This poor old puppie I picked up on the "Evil Empire" has one 6146B and one 6146A. Only getting about 55 watts out on CW. seems a tad low. And mixing tube types doesn't look good.