[TenTec] [] Running a Century 21 on external 12V power

[Josh Gibbs]

Just when you thought this thread was done... some interesting new
information!

It seems that Ten-Tec started adding in additional shielding for the
transformer at some point. Mine does not have the shield!

For reference here is one with the shield:

https://drive.google.com/open?id=0B_pjAwEfeYcdWTNrUUhPQlk4ZlU

And here is mine:

https://drive.google.com/open?id=0B_pjAwEfeYcdOUdHVW5VUlJmcVk

I'm going to make up a shield like this with some aluminium and see if it
helps with the hum.

-Josh