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Would a single DALE 100W 6.2 OHM resistor, housed in a case with binding posts, be adequate enough to use as a dummy load for amp repair? Assuming the amp under test was rated for 8 or 4 ohms.
thank you.
thank you.
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If you already have one, I'd say use it.
If it were me, I wouldn't box it up, I'd mount it in free air. I have a couple 250w Dales mounted to a aluminum plate about 15" square. That plate is bolted up under my benchtop. Wires run up to jacks over the bench on my riser. (I have a couple more loose for when I need them)
I have 8 ohm resistors so I can parallel them for 4.Education is what you're left with after you have forgotten what you have learned. -
...mount it to the "inside" (with copious themal 'goop' compound) of large 3-inch diameter can with a 3"-muffin fan connected to one end = air-cooled, circular, heat-sinked, load-resistor....and the Devil said: "...yes, but it's a DRY heat!"Comment
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Maybe if it was an aluminium can, but thin-gauge steel is a pretty lousy heatsink. I've been burned before (literally as well as metaphorically) trying to make heatsinks out of steel.
I use a bunch of power resistors bolted to an aluminium plate, the same as Enzo does.
I also bought a huge 10" long wirewound resistor off Ebay, but it turned out to be made of iron wire that gave it a high inductance, as well as making it sing audibly when used as a power soak. I think the inductance is good for a power soak, because voice coils have inductance too, but it's pretty useless for accurate power measurements."Enzo, I see that you replied parasitic oscillations. Is that a hypothesis? Or is that your amazing metal band I should check out?"Comment
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You COULD mount it in a gallon paint can - no paint of course. and then fill the can with mineral oil. Mount terminal posts on the lid and seal it.
In the old heathkit "Cantenna" RF dummy load, they did that. The oil helped dissipate the heat.
Of course part of the reason they did that was that the can acted as a shield, so your dummy load was not broadcasting RF all over while you tested something.Education is what you're left with after you have forgotten what you have learned.Comment
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Ah yes..... the red, black and white paint can.
Could I use olive oil and use it for deep frying? Wait, there's a restaurant 3 doors down. I'll run some wires underground to their kitchen and tap into their deepfrier.
thanks for the info!!Comment
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