Ben Waylin
Banned
The ones between the resistors.Which ones ?
Naw, that's 600V Teflon coated wire.The ones between the resistors.
Cameron made me an attenuator years ago. He used solid wire. I’ll find a pic of it.Naw, that's 600V Teflon coated wire.
Yeah, I buy that from ValveStormCameron made me an attenutor years ago. He used solid wire. I’ll find a pic of it.
Except you forgot to account for thermal degradation. That principal doesn’t work for high power dissipation resistors - you have to have a thermal coupler that acts as a safety off to prevent thermal runaway and risk of fire.Resistors in parallel, resistance halves and power handling doubles.
The previous photos kind of hide it, I know..Except you forgot to account for thermal degradation. That principal doesn’t work for high power dissipation resistors - you have to have a thermal coupler that acts as a safety off to prevent thermal runaway and risk of fire.
That’s good design practice however it doesn’t nullify the need to know the RMS rating after accounting for thermal heat soak even with fans and heat sinks. Make sure you’re not building a benchtop fire starter hoping you have headroom. 250W resistors seem like a lot but they really aren’t after thermal derating. For example when I spec’d my resistor load for measuring maximum power THD of tube amps I was looking at using thousands of watts of high power resistors to get the thermal stability under control.The previous photos kind of hide it, I know..
But there's a large, finned aluminum heat sink under the power resistors, and they are bolted to it with heat sink grease.
I was interested in how this version would handle heat dissipation. Previous purely resistive units I built would get warm to the touch, after running a cranked 100w amp into it for several hours..That’s good design practice however it doesn’t nullify the need to know the RMS rating after accounting for thermal heat soak even with fans and heat sinks. Make sure you’re not building a benchtop fire starter hoping you have headroom. 250W resistors seem like a lot but they really aren’t after thermal derating. For example when I spec’d my resistor load for measuring maximum power THD of tube amps I was looking at using thousands of watts of high power resistors to get the thermal stability under control.
Just be mindful of the circuits limits and design a fail safe if you can.
I was interested in how this version would handle heat dissipation. Previous purely resistive units I built would get warm to the touch, after running a cranked 100w amp into it for several hours..
Amazingly, this unit barely gets above room temperature, due to the thermal mass and wattage rating of the resistors.
heat sink grease.
Here's a really good thread we had going on that very question on TGP a few years ago..That’s fantastic, is it more transparent than my ole Hotplate?
May 08, 2019
A purely resistive load is going to work best for you if you're using it to load down a tube amp and then feed a line-level signal off the resistive load into another amp.
Here's another interesting take on it.. the Weber Mass:
Just voted for you.Yeah, I buy that from ValveStorm
https://www.valvestorm.com/Products/Wire
Don't forget to smash that like button, and vote for me !
Asoonah Numunu !!!The guys you asked us to vote for in this thread .... some have intelligence and some have hope to being rational or sane .
Proof that MAGA is like Kriptonite to some folks .
Picasso is a rotten soul .... kind of like a syphlitic vagina that has been ran over, repeatedly for a week, like road kill on the intellectual Freeway.... Picasso is a lost cause .... I could feel sorry for him .... but I'd rather laugh at him .
*kryptoniteThe guys you asked us to vote for in this thread .... some have intelligence and some have hope to being rational or sane .
Proof that MAGA is like Kriptonite to some folks .
Picasso is a rotten soul .... kind of like a syphlitic vagina that has been ran over, repeatedly for a week, like road kill on the intellectual Freeway.... Picasso is a lost cause .... I could feel sorry for him .... but I'd rather laugh at him .