[TowerTalk] Fwd: Oil For Dummy Load

[TexasRF at aol.com]

What is wrong with using distilled water, $1.50 per gallon at Walmart?  
Works just fine for amplifier cooling, no problem at 2000vdc and 1296 MHz.  Not 
flammable either!
 
73,
Gerald K5GW
 
 
 
 
 
 
 
In a message dated 12/4/2015 11:33:46 A.M. Central Standard Time,  
towertalk at contesting.com writes:

I dime  in the discussion, why not use something with the lowest viscosity 
such as  kerosene. That way the heat would be more efficiently removed. 
Kerosene has a  relatively low flam point so, unless you allow the temperature 
to rise too  much.


I, myself use a home made dummy load made from resistors  packed in TO-220 
capsules and mounted on a large, flat heat  sink.


Hans - N2JFS.



-----Original  Message-----
From: Bryan Swadener via TowerTalk  <towertalk at contesting.com>
To: 'TowerTalk'  <TowerTalk at contesting.com>
Sent: Tue, Dec 1, 2015 6:44 pm
Subject:  Re: [TowerTalk] Oil For Dummy Load

Gary K4FMX asked only about the  derating chart.

Fortunately for myself, oil viscosity is immaterial  
since my HN31 won't ever see more than ~ 100W again 
and I'll never  need to change the FREE transformer oil. 

Instead, for high power  stuff, I use my scrap parts 
1500W (100% D/C) DL that uses small  flange-mounted 
RF resistors. It's actually smaller than my HN-31.  

vy 73,
Bryan WA7PRC



----- Original Message  -----
> From: D. Scott MacKenzie
> To: Bryan WA7PRC
> Sent:  Tuesday, December 1, 2015
> Subject: RE: [TowerTalk] Oil For Dummy  Load
> 
> Unfortunately they don't give the viscosity of the  oil.  Most transformer
> oil is mineral at a viscosity of 10-20 cst  @ 40C.  However, mineral oil 
can
> range from 10-1000 cSt.  An  identical viscosity mineral oil would 
perform in
> an identical  fashion.  
> 
> 
> -----Original Message-----
>  From: Bryan WA7PRC
> Sent: Tuesday, December 01, 2015 12:53 AM
>  To: towertalk at contesting.com
> Subject: Re: [TowerTalk] Oil For Dummy  Load
> 
> The chart is here:  http://www.tinyurl.com/wa7prc-cantenna
> 
> My scrap parts 1500W  dummy load is here: 
http://www.tinyurl.com/wa7prc-dummy
> Though all the  parts were free to me, outfits such as Henry Radio
> 
>  (http://stores.ebay.com/Henry-Radio) sell RF power resistors for  
reasonable
> cost on ebay.
> vy 73 es gl,
> Bryan  WA7PRC
> 
>>  Date: Mon, 30 Nov 2015
>> From:  Gary K4FMX
>> Subject: Re: [TowerTalk] Oil For Dummy Load
>>  
>> There used to be a chart on the side of the Heath cantena that  showed 
>> the difference between transformer oil and mineral oil as  far as 
>> power/time. As I remember it was rather a significant  difference.
>> 
>> 73
>> Gary   K4FMX
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