[TowerTalk] Heath Cantenna

[Michael Tope]

----- Original Message -----
From: "Jim Lux" <jimlux at earthlink.net>

>
>
> Thermal properties are basically the same as USP mineral oil (drugstore
> oil).  The big differences:
>

Jim are you sure about that? The reason I ask is that both
the Heath and the MFJ Cantenna style dummy loads specify
duty cycle curves for mineral oil and "transformer oil". For
1KW, the duty cycle for mineral oil goes to zero, whereas they
specify 10 minutes (I assume this is from a room temperature
oil baseline) for transformer oil. Either Heath and MFJ cooked
the numbers to sell more transformer oil (MFJ sells it for
$25/gallon), or "transformer oil" is actually better at pulling heat
away from the Carborundum resistor.

In any case, if this is wrong, I would like to know. Getting
mineral oil in small quantities is a lot easier and cheaper than
trying to find real transformer oil.

73 de Mike, W4EF...............................................