One good point to remember, regardless of what oil you use: Don't get it
too full in the can. I left what I thought was plenty of expansion room in
my Cantenna (about 3/4") and when I was testing an amp into it with a
serious load, ended up with transformer oil (non-PCB type) all over the
place from the relief valve. Finally took the level down to about 1-1/4" and
never had that problem again, although the oil doesn't quite cover the
resistor 100% now. It's amazing how much oil can expand when heated. It's
also amazing how fast 1500W into a 1000W "derated" load can heat the oil.
:-)
73, Jerry W5KP
----- Original Message -----
From: "Jim" <w7ry@earthlink.net>
To: <TOWERTALK@contesting.com>
Sent: Friday, January 25, 2002 12:19 PM
Subject: Re: [TowerTalk] Oil for dummy load
>
> You can buy mineral oil at any good farm supply store or a store that has
> item for treating farm animals.
>
> Mineral oil is used for horses and cattle that are having digestive
> problems. My veterinarian used to pump it into one of my horses on a
regular
> basis....Needless to say....The horse is no longer with us.
>
> Expect to pay 20 or 30 bucks a gallon for it.
>
> 73
> Jim W7RY
>
> ----- Original Message -----
> From: Stu Greene <wa2moe@firstinter.net>
> To: David Clemons <dave@egh.com>; <TOWERTALK@contesting.com>
> Sent: Friday, January 25, 2002 12:02
> Subject: Re: [TowerTalk] Oil for dummy load
>
>
> |
> | At 12:42 PM 1/25/02 -0500, David Clemons wrote:
> |
> |
> | > The older transformer oil contained PCBs. If you use that
type
> | > of oil, you do not want to get it on you when you work with it
> as
> | > exposure to PCBs can possibly lead to cancer. The newer
> transformer
> | > oil might not contain PCBs, but I don't know how to tell the
> | > difference between new and old. Mineral oil, if it will
> dissipate
> | > the heat, definitely sounds better.
> | I agree. I don't know how to tell the difference between transformer
> oils.
> | I was aware of the problem with transformer oil in 1977 (the Hudson
River
> | was being treated for the junk that General Electric dumped into the
> river,
> | and my Heath dummy load was filled with mineral oil in 1977 (lots of
> | bottles) and is still in use. It dissipates heat nicely and obviously
> does
> | not contain anything but mineral oil, a laxative.
> |
> |
> | ________________________________________________________________________
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> | Order online at http://store.eham.net.
> | -----------------------------------------------------------------------
> |
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> |
>
>
>
> ________________________________________________________________________
> Where do you get ICE bandpass filters & beverage matching boxes? The
> same place that pays for the hosting of this list: The eHam Store.
> Order online at http://store.eham.net.
> -----------------------------------------------------------------------
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
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>
>
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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-----
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