Hi Rik is sounds like our toasers and kettles should all be subject to a
"swearing-in" session !! Sorry my company used to sell CB sets at one time.
Alan G3NYK
----- Original Message -----
From: "Rik Strobbe" <[email protected]>
To: <[email protected]>
Sent: 31 January 2005 14:45
Subject: Re: LF: Dummy loads for LF
Hello Bob, Gary, Markus and others,
over the past days a lot of household equipment has been suggested as 136
kHz dummy load.
I wonder what the "cold" resistance of some of these devices are. Most
metals have a positive temperature coefficient of about 0.3 to 0.5 % per
degree centigrade (iron : 0.5%, copper : 0.4%, aluminium : 0.4%).
For oil jacket heaters the temperature at full power may be only 40
degrees
above room temperature (= 20% increased resistance) but for devices like
toasters the change very large.
So a 1000 W toaster (@ 220 V) will be about 50 Ohm when loaded with 1kW
but
probably much less if loaded with only 100 Watt.
73, Rik ON7YD
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