I've fallen behind. Just finished this and then that...
I've been trying to figure out the codes on my Amperex Bugle Boy 6DJ8's...so far I know they're Holland made because of the delta sign. I assume they are 50's or early 60's but haven't figured it out yet. With a magnifying glass and flash light just so...I think I'm reading delta, 4, one or I, 2 or Z. Etched on the bottom of both tubes. My eyes aren't too good. Any Help?
PS...OK, I think I have it... delta 4 I 2...which means, Herrlen, Holland made, 1964, September, 2nd week.