Hello,
As I continue working on the Emerson 587 b chassis, this evening using a variac and two meters,
one for the ac the other for dc. All went well. Radio
plays very well. Now for my questions, what happens to the tube filament resistance as the radio plays?

Knowing the filament resistance(cold) and the input AC
voltage. Can Ohm's law be used to calculate the current
the second the is turned on?

:
:Knowing the filament resistance(cold) and the input AC
:voltage. Can Ohm's law be used to calculate the current
:the second the is turned on?
:

Sure, this is called "inrush current" and is a useful calculation when selecting a fuse to protect the set if one wasn't used in the original design.

:
::
::Knowing the filament resistance(cold) and the input AC
::voltage. Can Ohm's law be used to calculate the current
::the second the is turned on?
::
:
:
:Sure, this is called "inrush current" and is a useful calculation when selecting a fuse to protect the set if one wasn't used in the original design.
:
:
Thank you!!

:Hello,
: As I continue working on the Emerson 587 b chassis, this evening using a variac and two meters,
:one for the ac the other for dc. All went well. Radio
:plays very well. Now for my questions, what happens to the tube filament resistance as the radio plays?
:
:Knowing the filament resistance(cold) and the input AC
:voltage. Can Ohm's law be used to calculate the current
:the second the is turned on?
: Check on the other posting about the pilot lamp changing brightness. It's in parellel with the rectifier tap. There is a good explanation on this subject.

:Hello,
: As I continue working on the Emerson 587 b chassis, this evening using a variac and two meters,
:one for the ac the other for dc. All went well. Radio
:plays very well. Now for my questions, what happens to the tube filament resistance as the radio plays?
:
:Knowing the filament resistance(cold) and the input AC
:voltage. Can Ohm's law be used to calculate the current
:the second the is turned on?
: Check on the other posting about the pilot lamp changing brightness. It's in parellel with the rectifier tap. There is a good explanation on this subject.

:Hello,
: As I continue working on the Emerson 587 b chassis, this evening using a variac and two meters,
:one for the ac the other for dc. All went well. Radio
:plays very well. Now for my questions, what happens to the tube filament resistance as the radio plays?
:
:Knowing the filament resistance(cold) and the input AC
:voltage. Can Ohm's law be used to calculate the current
:the second the is turned on?
: Check on the other posting about the pilot lamp changing brightness. It's in parellel with the rectifier tap. There is a good explanation on this subject.