So I went a little over on buying bulk parts

phyrrus9 · 07-24-2018, 06:08 AM

Well, some of you may have read this thread. While ordering parts, I didn't feel like paying the premium for single quantity parts, so I went overkill with bulk options. What circuits do you want me to build with the leftovers?

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mothered · 07-24-2018, 11:46 AM

If I'm not mistaken, all up, that's relatively cheap yes?

skrtja · 07-24-2018, 12:35 PM

Sell them on eBay : Profit.

Vultra · 07-24-2018, 02:29 PM

Dayum, all of that stuff just for the new project with the fan?

phyrrus9 · 07-24-2018, 03:26 PM

(07-24-2018, 11:46 AM)mothered Wrote: If I'm not mistaken, all up, that's relatively cheap yes?

For the part quality (notice those transistors can handle 30A@60V, which is 1,800 watts), yes its all extremely cheap.

(07-24-2018, 02:29 PM)Mimiakira Wrote: Dayum, all of that stuff just for the new project with the fan?

I actually only needed 4 components and a board for this project, but it would have cost me like $18 for those 4 individually, or $90 for a shitload (enough to make 20 and still have spare parts)

mothered · 07-24-2018, 03:38 PM

(07-24-2018, 06:08 AM)phyrrus9 Wrote: What circuits do you want me to build with the leftovers?

Knowing you, you'd probably build a nuclear power plant.

On a serious note, what can they actually be used to build?

phyrrus9 · 07-24-2018, 04:40 PM

(07-24-2018, 03:38 PM)mothered Wrote:
(07-24-2018, 06:08 AM)phyrrus9 Wrote: What circuits do you want me to build with the leftovers?

Knowing you, you'd probably build a nuclear power plant.

On a serious note, what can they actually be used to build?

I actually do want to build a low scale nuclear power plant (like the size of a 5 gallon bucket), but thats gonna take a lot more research and learning before i go anywhere near the materials for that.

As for this, I'm using it to make a hybrid analog-digital circuit to drive a 2-speed fan for my car's radiator. Basically I'm using an NTC thermistor taped to the lower radiator hose. As temperature increases the resistance across it will decrease, allowing more of the current to flow through it. I'm adding resistors before the NTC so that I can tune the level of current flowing there so that the voltage right before the NTC will be exactly 1.5v at the temperature I want. Before the NTC I've got a p-MOSFET (turns on when input is off, aka below 1.5v). So when the thermistor gets hot enough, the p-MOSFET input will be driven low causing the output to be high and supply power to a relay that will switch from low to high speed on the fan. As it cools back down the transistor will turn back off and if everything goes right it will cycle back and forth at 65-70C