k3hvg wrote:
Many, if not most, of the smaller (read: 5Y3, 5U4, 5V4, etc.)SS
replacements do not have a dropping resistor molded inside the unit.
I/we use a series of SS replacements up to and including the 3B28 and
4B32. The latter two SS replacements do have the resistors owing to FAA
purchase specs, however. Just be sure and include resistors in your
replacement design. As far as filament "stripping", as alluded to by
another posting, some say its a big deal. If the unit is not being
turned on and off many times a day, every day, I can't see it being a
problem.

Stripping is a big deal with some big power tubes... I have never seen it
be a problem with small signal tubes and any receiving tubes that are
rated for series-string operation will not have any issue.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."