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
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
Thanks Carter. I tried some shielding using some thin steel I had, but I want to replicate the shield that Ten-Tec used. They must have done that for a reason! It turns out that my C21 digital is a v
The effectiveness of magnetic shielding increases dramatically with metal thickness so you are headed in the right direction. Gary _______________________________________________ TenTec mailing list
Thanks, Josh, for bringing up this interesting discussion. After having C21s (still have two) for many years I have never checked into the "how" and "why" some things were done in the production of t
Mu Metal is available as a foil that makes an easy add on for existing steel chassis. Stuart Rohre K5KVH _______________________________________________ TenTec mailing list TenTec@contesting.com http
For magnetic fields like around a power transformer, the most effect of shielding is with steel or Mu Metal. Stuart Rohre K5KVH _______________________________________________ TenTec mailing list Ten
I'm learning a lot about shielding... tons of good resources on the Net. This article was particularly useful: http://www.ets-lindgren.com/pdf/emctd_1293_weibler.pdf The fact that Ten-Tec used alumin
http://www.ets-lindgren.com/pdf/emctd_1293_weibler.pdf The fact that Ten-Tec used aluminum when steel would have been cheaper is interesting, especially since steel is much better at attenuating magn
I agree Carter. Here is another thought... perhaps its a heat-sink, and not a shield? That would explain the use of aluminum. Now that I think of it, when I removed the transformer there was a square
Maybe the reason was structural integrity, not shielding. Gus Hansen KB0YH _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/mailma
OK, the reason TT used aluminum is they had an aluminum box plant, and lots of aluminum. Aluminum is great for shielding electric fields, while steel and mumetal shield better for magnetic fields whi
The extra sheet of metal stiffens the place where the transformer mounts. A common way of building extra strength. Stuart Rohre K5KVH _______________________________________________ TenTec mailing li
Ten Tec once stated directly in their ads that they used Aluminum because it was lighter. I remember this because many hams at the time complained to Ten ten that TenTec radios felt sort of cheap sin
Very good info, thank you! Check out this neat article from 73 Magazine, Dec. 1977: https://archive.org/stream/73-magazine-1977-12/12_December_1977#page/n29/mode/2up There is the man himself, and a p
I believe many Collins radios were also aluminum. At least my 75A4 is. Also the big Hammarlund SP-600 is aluminum. I'm sure it's easier to work with. I've had 3 or 4 Century 21's and never had a hum
Thanks Josh. That was a nice little trip down nostalgia lane! 73, ron w3wn Very good info, thank you! Check out this neat article from 73 Magazine, Dec. 1977: https://archive.org/stream/73-magazine-1
No worry about Mumetal at UHF, as there are no Century 21's tuning UHF! K5KVH _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com/mai
FB. No worry about Mumetal at UHF, as there are no Century 21's tuning UHF! K5KVH _______________________________________________ TenTec mailing list TenTec@contesting.com http://lists.contesting.com