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This is about the adjustable, constant current load PCBs that Shane
Trent made available starting a year ago in conjunction with <a
href="http://fettricks.blogspot.com/2014_06_01_archive.html">this
blog post</a>.<br>
<br>
I built one of these and tested it to confirm it will provide an
easily adjustable, constant current load from a small fraction of an
amp up to a few amps, depending on the power involved. As near as I
can figure the transistor doing the work in combination with the
heat sink it's bolted to can deal with 18 watts before the
transistor junction temperature limit is exceeded. <br>
<br>
I'm almost done building a second one that could be a "TriEmbed Club
Loaner" for folks that would like to experiment with it. <br>
<br>
Some of these PCBs were claimed at the last meeting but there is at
least one more available for anybody that would like it.<br>
<br>
My builds use a precision five watt resistor in place of the 10
little through hole ones, and I've got proper screw terminal blocks
for the load connection. It would be great to get input on a decent
connector for the current sense. Jamming multimeter probes into
these holes is only interesting for a short time.<br>
<br>
It should be relatively straight forward to make this load
programmable by insinuating a control voltage into the op amp
circuit to functionally replace the adjustment pots. If somebody
would like to pursue this I'm sure we'd be relaxed about nearly any
level of hacking of the loaner in return for design details.<br>
<br>
-Pete<br>
<br>
<br>
<br>
<br>
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