Quote:
Originally Posted by Phil Nelson
I cost just under $180 to FedEx the empty box coast-to-coast. It's the size that made it expensive; the shipper told me it could have weighed up to 200 pounds without increasing that charge. (UPS would have cost even more, if you're wondering). My box was about 2-3 inches taller than it really needed to be. I don't know if making it shorter would have gotten it under some size limit.
I couldn't resist setting the new tube into the cabinet and trying on the retainer ring.
That anode connection is awfully close to the ring. Seems like you're asking for trouble (arcing) if you don't cut away some of the ring.
Looking ahead to when I really install it, the tube has an aquadag coating, so I guess that means fashioning a ground connection.
I don't have any use for the old insulating skirt. I wonder if it would be useful to cut away the bottom of the skirt and retain the rest (the waist, if you will) to go between this ring and the tube's neck and bell? I could even pigtail onto the old ultor connection -- which is built into the skirt -- to make the new aquadag connection. (I already cut off most of the old ultor lead to make my new anode lead.) That would mean cutting a hole in the skirt for the anode lead, of course.
On the other hand, if I butcher the skirt, I couldn't reuse it in the remote event that I run across a good 21AXP22 or have mine rebuilt . . . .
Phil Nelson |
Sylvania published a brochure back in the late 60s about installing rare earth tubes in older receivers titled "Color Fidelity for Older Receivers". The part on CTC-4 showed a small portion of the skirt cut away from the anode area of a 21FB to allow for the connection of a compatible lead and boot. I scanned it, and have it somewhere, but not on this machine. I'll look for it tomorrow and if I find it I'll post it here. Should be an easy job to do, and will prevent arcing. I'm considering putting a 21CY in my CTC-4 but haven't yet made up my mind about that.
Good luck Phil!
Kevin