u/SolitaryMassacre

I have been learning about RC delay circuits recently. I understand the math and everything, it makes sense.

The real question I have is why/how.

For example, what about the electric field or potential or whatever term it is that determines the capacitor must charge first before the "rest" of the wire sees the source voltage? Why is the current simply not halved at the junction as it is with basically anything else?

I would like to combine two switches into one.

I have the following config:

Circuit A - B via one switch. Circuit C - D via a second switch.

I would like to combine them into one switch. A - B is a 120V AC connection, C - D is a speaker connection.

A switch with say 3 positions. 0th position, everything off. 1st position, A-B connected, C-D disconnected, second position, C-D connected whilst keeping A-B connected.

Does this even exist? I googled for hours and couldn't find anything. The most I could find were switches that 0th pos, everything off, 1st pos, A-B connected, C-D disconnected, 2nd pos, C-D connected, but A-B disconnected. Not what I want

Thanks all

Looking to get a Prius.

Have been doing a lot of research and basically it comes down to "just expect to do maintenance" which I am not afraid of as my Saab has many gremlins.

I'm unsure of the two I am looking at.

2010 Toyota Prius 150K

Works. Owner says nothing is wrong (granted I do not believe them entirely) but it is drivable. I am assuming the hybrid battery will need replacing soon.

2017 Toyota Prius 2 125K

First con, reconstructed title (I'm not sure why, my guess was in accident. I should probably get the carfax for it).

Has list of issues:

• AC is not working (no idea why, kind of priority for me as I live in FL)
• Check engine light is on, evaporation canister (not a huge priority for me unless it drastically affects performance)
• Stuck open shutter (I read about this, I can fix this).

6500

I'm not worried about physically doing the work to either of them for whatever they may need. I can even reman the battery myself (I do microelectronics repair).

Both asking prices are a bit too high for me, esp the 2010 seeing as it will need a battery very soon if not other things as well.

My unknowns are basically the differences between the years in terms of features. I noticed the 2010 doesn't have an LCD screen (but I could install one very easily for a couple hundred, would be nice for navigation).

Basically, what am I missing out on by buying the older one for cheaper vs the newer one? The newer one does look a lot nicer but thats not a huge deal breaker for me

I have a spot welder for DIY projects.

Thought I would replace my cells in my eBike/eScooter/eSkate myself to save money. But from what I can find online using this link the cost of batteries are incorrect on that direct link. But when I follow the links to buy them, they are like 6 bucks a piece. Which my pack on my ebike is ~104 cells, making that a 600 dollar project. Where a full replacement is the same cost.

Am I missing something here?

Maybe I am replacing them with better quality batteries? I guess I would have to open up the case to see exactly what batteries were used. But I am surprised to see this costing more than a new complete battery

https://preview.redd.it/4z1ii622v43h1.jpg?width=3072&format=pjpg&auto=webp&s=acfdd66bf0fe645eb037ed6817fe2e8f93d2ce31

Laptop battery connector. (Maybe used a bit too much solder but was hard to get the iron under there)

Happy to help u/cave_maiden out with their laptop. A successful repair!

This is a part 2 from my first attempt found here

I think I made some decent strides! I added more heat from the bottom using this homemade setup. It works VERY well I quite love it.

https://preview.redd.it/8p82yezx0tyg1.jpg?width=3072&format=pjpg&auto=webp&s=56b13db7ab55aef71413fae55e057a2e320e2da2

Here are the results:

https://preview.redd.it/yd0euqlz0tyg1.jpg?width=4080&format=pjpg&auto=webp&s=6e17bc2ac583634dcb9ff2688c5cb7eb5863b607

https://preview.redd.it/95couqlz0tyg1.jpg?width=3072&format=pjpg&auto=webp&s=fa6b6bb2fe78cac08161319089763a645202db76

I still had a bit of the PCB come off on near the solder joints. However, it only happened in the lower and left half where I started. I think I was pressing too hard with the desolder wick as it *did not* look like that before using the wick. I then pressed lighter for the top and right sides.

Would love some feedback! Thanks!

EDIT: Removing the PCB from the heatsink is impossible. Else, would have done that

I want to get rid of the noisy old power supply in my guitar amp.

Here is the circuit board that would be accepting the voltages. On the left side, you can see the plug pinouts. -HV(-18V), +HV(+18V), and +8V would be created from the 20V 100W power source (note: this is a PD 100W trigger board). Each input goes to a voltage regulator, for the 8V, I was just going to feed the regulator the +20V as it is still within its max. It is already attached to a heatsink (the entire chassis) so heat shouldn't be a problem.

https://preview.redd.it/ebih1d6q2fyg1.png?width=1456&format=png&auto=webp&s=7f6368821b9d3221fba2b63d58c96e270477c4d8

I found this: Generating Negative Voltages from a Positive Voltage Supply: Market Requirements and Solutions | Analog Devices

And it looks like I want a flyback inverter or power module (however, I think because of the circuitry, it needs to be isolated. So a flyback would be needed). I just am unaware of what flyback I need. A simple plug and play would be amazing. I can build it myself if needed.

The only reason I am wanting to use 1 PD trigger board is so it can function using a battery pack. This isn't a direct requirement and I am seeing what options I have. If this gets too costly/difficult, then I will simply add a second trigger board for the -HV circuit and use 2 battery backs.

The max wattage of the entire guitar amp is 60W with the speaker being 40W (20W overhead is probably the heat and such consumed). So a singular 100W trigger board should be more than enough.

Thanks all for the input!