Note that the only good ones are the IERC shields made to MIL-S-9372 specs. Of those, only the ones which were made on alternate Tuesdays that coincide with a new moon between the hours of 7:14 AM and 1:23 PM are worth having. The others made to this spec resonate imperceptibly at frequencies between 516 Hz and 2.16 kHz. This resonance is impossible to see on any test equipment. Only a true expert's ear can hear it. Other IERC shields also have resonance issues, mostly at negative frequencies which cancel out the positive counterparts in music thus leaving the music sounding hollow and unfulfilled. Non-IERC shields sound metallic and aren't worth the metal they're made from.
Best Regards, Michael, K3MXO, CBLA #6, BL01hx15np24 ... or there abouts What was the greatest thing before sliced bread? http://www.nationalmssociety.org/chapters/NTH/index.aspx http://wh7hg.blogspot.com/ http://kludges-other-blog.blogspot.com Hiki Nô! -----Original Message----- From: Boatanchors [mailto:[email protected]] On Behalf Of Brian Carling Sent: Sunday, 25 May, 2014 13:44 To: Bob Jackson Cc: porch.boat; puck.boat; qth.boat Subject: Re: [Boatanchors] Tube shields I have a bunch of the black ones if anybody is interested... Best regards - Bry Carling > On May 25, 2014, at 6:48 PM, "Bob Jackson" <[email protected]> wrote: > > I always assumed that tube shields were used to keep stray RF either in or out of the tube or both. Are there other reasons as well like keeping them securely in their sockets via the little springs inside the shield? > > Bob > ______________________________________________________________ > Boatanchors mailing list > Home: http://mailman.qth.net/mailman/listinfo/boatanchors > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > List Administrator: Duane Fischer, W8DBF > ** For Assistance: dfischer at usol.com ** > > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html _______________________________________________ Boatanchors mailing list [email protected] https://puck.nether.net/mailman/listinfo/boatanchors _______________________________________________ Boatanchors mailing list [email protected] https://puck.nether.net/mailman/listinfo/boatanchors
