Search found 38 matches

by solar3000
Wed May 29, 2019 4:56 pm
Forum: General Discussion
Topic: cutoff circuit for battery
Replies: 2
Views: 121

cutoff circuit for battery

What's a simple circuit for low voltage cut-off?
I'm thinking of several circuits. One [li-ion] 3 volt low; 4 volt high. Another with a minimum of 12 volts.
by solar3000
Thu May 16, 2019 5:00 pm
Forum: General Discussion
Topic: Li-Po cell Id.
Replies: 13
Views: 372

Re: Li-Po cell Id.

by solar3000
Fri May 10, 2019 6:47 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 237

Re: [18650] rechargeable battery + super capacitor

what about this guy: a 45F 5.6 volt super duper capacitor. And how is it only $11USD?

https://www.digikey.com/product-detail/ ... ND/7318587
by solar3000
Fri May 10, 2019 4:15 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 237

Re: [18650] rechargeable battery + super capacitor

Well, I'm thinking a super cap in parallel with the li ion battery, before the USB booster. So what's a li ion, 3 volts to 4 volts? And how long does it take to switch a battery? Perhaps 5 to 10 seconds? I'll stick to the high side of the drain, say 160 mA. I saw a super cap rated at 5v at 4F. Some ...
by solar3000
Thu May 09, 2019 9:47 pm
Forum: General Discussion
Topic: CNC Router anyone?
Replies: 5
Views: 258

Re: CNC Router anyone?

....7 days later....
Hi friend. Its very lonely here.
I would love to have a CNC, but I have no space in my tiny apartment.
I need a bigger place to go with that CNC.
I would love to have a pick-and-place circuit board maker thing.
by solar3000
Thu May 09, 2019 9:44 pm
Forum: General Discussion
Topic: Is Nuts and Volts dead ?
Replies: 8
Views: 581

Re: Is Nuts and Volts dead ?

I like my magazines carved on clay tablets.
by solar3000
Thu May 09, 2019 9:41 pm
Forum: General Discussion
Topic: [18650] rechargeable battery + super capacitor
Replies: 7
Views: 237

[18650] rechargeable battery + super capacitor

I'm building a pocket project that I'm going to put in my pocket and walk around with. Inside is a battery and a 3.6v to 5 v boost. Also inside is a raspberry pi zero, but it could be any small electronics as well. When I need to change battery, I would have to shut down the load. I'm wondering if I...
by solar3000
Fri Oct 19, 2018 8:42 am
Forum: General Discussion
Topic: USB-C, 100 watts?
Replies: 2
Views: 467

USB-C, 100 watts?

I've been reading about how USB-C can transfer 100 watts. But no one seems to know how.
Not at five volts or else the copper would have to be an inch thick.
by solar3000
Thu Jan 18, 2018 7:43 pm
Forum: General Discussion
Topic: Hammond die cast al case, heat sink?
Replies: 11
Views: 2926

Re: Hammond die cast al case, heat sink?

thanks. I dremeled it shiny. Definitely not as silvery as Al in heatsinks. But plenty of surface area for a single transistor.

looks like compressed particle aluminum. Like compressed wood.
by solar3000
Sun Jan 14, 2018 4:20 pm
Forum: General Discussion
Topic: Hammond die cast al case, heat sink?
Replies: 11
Views: 2926

Re: Hammond die cast al case, heat sink?

So, it sounds like you're saying the quality of aluminum is ok compared to the type of aluminum in a typical heat sink. I have no way to test the thermal conductivity of the aluminum, so ditto jwax. But I doubt Hammond purposely concocted thermo-insulating aluminum to make their boxes. I do believe...
by solar3000
Sat Jan 13, 2018 8:12 pm
Forum: General Discussion
Topic: Hammond die cast al case, heat sink?
Replies: 11
Views: 2926

Re: Hammond die cast al case, heat sink?

So, it sounds like you're saying the quality of aluminum is ok compared to the type of aluminum in a typical heat sink.
by solar3000
Sat Jan 13, 2018 4:54 pm
Forum: General Discussion
Topic: Hammond die cast al case, heat sink?
Replies: 11
Views: 2926

Hammond die cast al case, heat sink?

I have various Hammond cases.

It says die cast aluminum. But it feels like low grade aluminum. Looks like compressed wood. Well see for yourself and some of you already have ones.

Would it be a good heat sink?

https://www.hammfg.com/electronics/smal ... t/1590.pdf
by solar3000
Fri Jan 05, 2018 5:12 pm
Forum: General Discussion
Topic: LM 1084/338/317/etc... voltage drop at < 1A
Replies: 23
Views: 4566

Re: LM 1084/338/317/etc... voltage drop at < 1A

These just came in a hour ago.

https://www.amazon.com/gp/product/B00K8 ... UTF8&psc=1

Works great. No more hot capacitors.
by solar3000
Fri Jan 05, 2018 6:48 am
Forum: General Discussion
Topic: LM 1084/338/317/etc... voltage drop at < 1A
Replies: 23
Views: 4566

Re: LM 1084/338/317/etc... voltage drop at < 1A

yah. No more heat. The chip is just somewhat warm. So, now it does not drop voltage up to 1.5 amps at a setting of 12 volts. With 2 amps, the voltage drops to 9 volts. So, here I go again. Next step is to make a copper board or at least try a pre-made one like those from the dead Radio Shack. I'm su...
by solar3000
Thu Jan 04, 2018 11:00 pm
Forum: General Discussion
Topic: LM 1084/338/317/etc... voltage drop at < 1A
Replies: 23
Views: 4566

Re: LM 1084/338/317/etc... voltage drop at < 1A

Uhhh..huh-huh...problem solved. same circuit. I connected a 20W halogen bi-pin lamp one end to the ground (anywhere) and then the other pin directly to the output, even at the heat sink tab. The bulb lit up and didn't drop a tenth of a volt. The real problem is that shiitie solderless board that I p...