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AdrianH · 21st Jan 2021, 9:09 pm

This is something I will admit is a week subject for me Coils/inductances and induced emf with changing magnetic fields.

I am trying to read a series of articles from Practical Television circa 1957 and here is a partial copy of the text.: -

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Now I must be missing a point as I can not understand where the formula comes from and how they achieve the figure of 1.5KV they get.
If reading it correctly they say L = 10mH inductance, I = 1 Amp and tr = 7 uS or 0.000007 secs so I actually get 2K8 Volts.

So please where am I going wrong.

Adrian

21st Jan 2021, 9:09 pm	#1
AdrianH Octode Join Date: Mar 2020 Location: Blackburn with Darwen, Lancashire, UK. Posts: 1,573	Question on a bit of theory This is something I will admit is a week subject for me Coils/inductances and induced emf with changing magnetic fields. I am trying to read a series of articles from Practical Television circa 1957 and here is a partial copy of the text.: - Now I must be missing a point as I can not understand where the formula comes from and how they achieve the figure of 1.5KV they get. If reading it correctly they say L = 10mH inductance, I = 1 Amp and tr = 7 uS or 0.000007 secs so I actually get 2K8 Volts. So please where am I going wrong. Adrian __________________ Asking questions and learning, or trying to! Youtube EF91Valve