At 1/18/2008 09:00, you wrote: >Delrin (polyacetal) is a bad choice for RF applications. Its >dissipation factor is too high. It is a great "engineering plastic" >meaning it is strong physically but it is too lossy. Teflon (tm) is the >best, also rexolite for RF. Also most any ceramics. Corning has a line >of "machinable" ceramic if you can find it that works great for RF.
Not sure how common this stuff is, but TPX (a.k.a. polymethylpentene) has very low dielectric loss at microwave frequencies... and beyond. Bob NO6B
