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Show me your dummy load(s)!

The OP didn't mention what type of dummy load they were talking about in the topic!

Next we need to add power supply/battery pack tester dummy loads too :D (Note: PSU/battery pack dummy loads are electronically complicated (to deal with fixed voltages) versus RF dummy loads are physically complicated (to reduce inductance.))
 
Dummy loads for the giga-hertz crowd ECM radar jamming... Band 2, 2.5 and 3

Waveguide-Loads-and-Terminations.png
 
^^ Exactly the kind of physical dimensions needed to ensure that microwaves get fully trapped and dissipated within the cavity...

And for the power supply...
dummy250.JPG
And this is a homemade (simple... but do realize the complexity of what's inside the IC) ~250mA constant current dummy load - as long as the voltage is within range and the IC can handle it, a constant, approximately 250mA will flow from red to black.

Okay, I lied somewhat.

It was meant to be a constant current limiter for illumination LEDs, though the LED can be omitted and all of the power gets dissipated in the jig...
 
audiodummy said:
^^ Exactly the kind of physical dimensions needed to ensure that microwaves get fully trapped and dissipated within the cavity...

And for the power supply...
View attachment 2537504
And this is a homemade (simple... but do realize the complexity of what's inside the IC) ~250mA constant current dummy load - as long as the voltage is within range and the IC can handle it, a constant, approximately 250mA will flow from red to black.

Okay, I lied somewhat.

It was meant to be a constant current limiter for illumination LEDs, though the LED can be omitted and all of the power gets dissipated in the jig...
Click to expand...


Ahhh, yes. An "Active Load". Built a few of those for a former employer, but they were a bit bigger than yours. They could safely dissipate about 10kW....
 
drjim said:
Ahhh, yes. An "Active Load". Built a few of those for a former employer, but they were a bit bigger than yours. They could safely dissipate about 10kW....
Click to expand...

It was back in '80 I was working with active loads that were plumbed for cooling water. Used to think of them as water heaters... I don't remember the max loads. But they were for electric vehicle battery testing.
 
I have several sets of Dale 8 ohm 250 watt resistors. I intend to mount them on a heat sink.
 

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markthefixer said:
It was back in '80 I was working with active loads that were plumbed for cooling water. Used to think of them as water heaters... I don't remember the max loads. But they were for electric vehicle battery testing.
Click to expand...

We had a water cooled dummy load/calorimeter rated for 100kW continuous at Fermilab that we used for testing the RF power amps in the Booster and Main Accelerators.
 
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