Topband: 160 Meters Mobile Antenna

[Hardy Landskov]

At 08:06 PM 5/7/03 -0700, Bill Turner wrote:
>On Wed, 07 May 2003 20:00:52 -0400, you wrote:
>
>>PVC and PBT and other such plumbing pipe plastics are very
>>lossy for RF. 
>
>The traditional test for lossy plastic is to put a section of about
>six inches in the microwave for 20 seconds or so and see if it gets
>hot under full power.  To protect the magnetron, also put a small
>amount of water in there to absorb the microwaves if the plastic
>actually is loss free.
>
>-- 
That is a rule of thumb test. Many materials have a loss tangent that is
very high at 2400 MHz (microwave oven freq) but would be suitable at HF.
N7RT