[TowerTalk] Grey PVC Loading Coil

[Jim Lux]

At 09:37 PM 12/6/2006, Michael Tope wrote:

>----- Original Message ----- From: "Jim Lux" <jimlux at earthlink.net>
>
>>>
>>>I use black PVC as coil forms at 1200 watts on 160
>>>with no problems.
>>Black PVC, or is it ABS DWV (drain, waste, vent), which is actually 
>>a foam core, and even lower effective dielectric 
>>constant.  Although, being black, and pigmented with carbon, and 
>>foam cored, it makes a terrible insulator for HV use, particularly 
>>in electrostatic machines.  But at the voltages you're likely to 
>>see in an antenna system, it should be fine.  But in something like 
>>a Van deGraaff generator with a few microamps at 500 kV, it is horrible.
>
>Solid Black PVC, not ABS DWV. My scientific material selection
>process - found some laying on a shelf in the garage when I decided 
>to make the coils.

So you use the same technique as I use.. use what's laying around, 
and if it catches fire, see if you can figure out what went 
wrong.   (That's how I found out about the amazingly wide use of 
carbon black as a pigment.. It's something I knew, if someone had 
asked, but I never connected it to the electrical properties of paint 
and plastic pipe until I had some exciting experiences).

Jim