[Lowfer] Need dummy load resistors

[C. Turner]

For projects, one fairly cheap source of power resistors that are usable 
at RF are the thick-film devices available in various packages - such as 
TO-220.

One of several types is this one:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=TR35T251J-ND

In testing various devices from different manufacturers, they are pretty 
good through HF and still usable at 2 meters, with a VSWR of <1.3:1.  
I've also seen these devices used in microwave transverters as the main 
terminating load for the 2 meter IF.  Other places (Mouser, etc.) also 
sell these things and they are available in a variety of resistance 
values, tolerances, power levels and packages.

In free-air, they are capable of only handling 3-5 watts max, but their 
full ratings can be utilized by heat-sinking them.

Clint
KA7OEI/CT
> Hi all:
>
> I'm wanting to eliminate the coax jumper, " T " connector, clip lead
> setup I'm using now on my Hf to LF transverter. I want to add an 
> input " dummy load " on the board to tap power from. So, I need to
> know the proper type of resistor to use. I tried what looked to be
> power resistors from an old monitor, at 53.4 ohms with 1 watt out,
> the SWR to the 10 meter rig was 3:1 ... I tried a combination that 
> read 49.4 ohms, and still the same SWR. I can put the RS 25 watt
> dummy load back in line, and the SWR is flat. What type of resistor
> should I use.  Thanks for any info.
>
> 73 to all :::  
>
>
> Andy - KU4XR - EM75xr - Friendsville, TN. USA
> LOWfer Beacon " XR " @ 185.29875 KHz ( QRSS-60 )
> Coordinates:  N:  35º 43' 54" - W:  84º 3' 16"
> http://www.myspace.com/beaconxr
> http://webpages.charter.net/ku4xr/
>
>