[Amps] Is This 4CX1600B Still Good?

[k7fm]

"I'm not sure, but 2.3 ohms on a cold filament of a tube that size seems a 
bit high.
I've never measured the cold resistance on a 12 volt filament transmitting 
tube,
(only 5 or 7 volt tubes) but it still seems a little high.  I'd try the 
temperature
test like the previous poster mentioned."


The actual resistance is not material.  Filaments are basically, either open 
or shut.  If you measure resistance, they are not open.  Many of the 
inexpensive meters have at least a few tenths of ohms of resistance in the 
leads and often the connection will add resistance.  So, whether it measures 
1 ohm or 3 ohms, it means the filament is good and you can move on to the 
next step in the investigation.

Happy Thanksgiving,  Colin  K7FM