Dear Lowfers,

for my experiments I use commercial dummy loads, like my Rohde & Schwarz RD1/60, oil filled, 1 kW /60 Ohm with monitor output attenuation of about 40 dB with Dezifix-connectors (the sexless Bajonnet ones ...). A dry portable 150 W-Version I have too.

I definitely do not recommend homebrew constructions at these high power ratings. The danger of fire is to big, and resistors of adequate power rating are expensive too.  I bought  my collecton of attenuators at Ham Radio fair at modest prizes.  60 Ohm equipment  is not what hams like, but Power error is minimal when the attenuator output is terminated by a 50 Ohm-Power-Meter, or is not terminated at all (after an attenuation of 30ddbB or more ).

An other possible equipment is the noisy test load  KAM, "Kunstantenne mit Meßausgang" from late German Democratic Republic, designed for the transmitter KSG1300.

55, Hans-Albrecht

DK 8 ND

[email protected] schrieb am 08.11.03 18:52:32:
>
>
> With all the comments on Loads,,, put them in a container and add mineral
> oil
> would really boost their rating ,, just allow for some venting
>
> Bob K3DJC
>
> On Sat, 8 Nov 2003 01:23:05 +0100 [email protected] (jannsen)
> writes:
> > James Moritz schrieb:
> >
> > ...............
> >
> > > Several people have resorted to electric heating elements like
> > > toasters and fan heaters to make satisfactory LF dummy loads.
> >
> > Hi Jim es all,
> >
> > here are two dummy loads in use; one is a bulb 110V/DC500W, Z 35 Ohm
> > on 136kHz
> > (bridge measurement) and the other is made of four hollow ceramic
> > resistors
> > 200 Ohm/60W each, makes 200W only. but blowing air through the
> > resistors
> > (see attachment) makes a lukewarm 300W dummy on 136kHz (0,4uH only).
> >
> > I tried 800W. A peace of paper above the dummy caught fire within 10
> > sec.
> >
> > regards
> > Uwe/dj8wx
> >
> >
> >
>