Home  Resources  References  Tubes  Forums  Links  Support 
speaker prob or not ?
1/26/2008 5:46:49 PMBob H
Finally got my 16 tube wards 62-197 working. It
has 4 2a3 tubes feeding two 12 inch electro dynamic
speakers. Ran it on 90 volts for a while and now on
line voltage.Both field coils are warm-not hot but-
one seem quite a bit warmer than the other. Is this
a indication of pending problems? What should I look
for or expect?
Would not have gotten this far with my limited
knowledge except for the help of this site. Many
thanks to those of you who give of your time to help
us out.
Bob
1/26/2008 6:38:38 PMDoug Criner
Bob, that's quite a set! Two pairs of 2A3s in push-pull, one pair for each speaker: http://www.nostalgiaair.org/PagesByModel/339/M0011339.pdf

It looks to me like the two field coils are wired in parallel and have the same resistance (4500 ohms each). So measure the reistance of each coil, by itself (by unplugging the speaker).
Doug

Since the resistance is supposed to be the same for each and the two coils are in parallel, I would expect them to generate the same amount of heat.

: Finally got my 16 tube wards 62-197 working. It
:has 4 2a3 tubes feeding two 12 inch electro dynamic
:speakers. Ran it on 90 volts for a while and now on
:line voltage.Both field coils are warm-not hot but-
:one seem quite a bit warmer than the other. Is this
:a indication of pending problems? What should I look
:for or expect?
: Would not have gotten this far with my limited
:knowledge except for the help of this site. Many
:thanks to those of you who give of your time to help
:us out.
: Bob



© 1989-2025, Nostalgia Air