Amps VS volts... having a stupid moment

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wtp

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?

i still want to know how you phase d.c.
a.c. yes i got that one
only studied 2 years in high school and 1 at college level
playing with radios and electronics since 1970.
 

Toastedwaves

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Here are my thoughts at this point.

Computer chargers are not 'smart' or 'dumb' enough to be connected in parallel. Not 'dumb' enough because they are not simple DC feeders, like a battery, as they do contain electronics that sense current output, making it adjust itself, and when sensing another charger's current it would try to balance both chargers, not making the difference between the two, resulting into a 'fight', with unpredictable results.

Not 'smart' enough because, chargers cannot adapt for applications they were not designed to do, are unadjustable except for volts/amps presets for universal chargers, dictated by the DC output plugs they come with, and they do not have selectable 'modes'.

The makers knew exactly what they were doing... marketing wise. Most laptop charger are not built to last, as I was warned about when I bought the computer by the sells person. The 'parallel' option would have been a good way to counter that planed obsolescence, but most importantly, offer power unit alternatives.

Feel free to express ideas about this. Your inputs is greatly appreciated. The 60w in a dark room. Thank you.
 
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WA0CBW

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discombobulated: "I would think that the power supply with the highest potential would dominate and the other would match it. You could put some diodes in each output for current protection."

You are right in that the one with the higher potential would dominate but the other would not match it because it is a "regulator" and is designed to provide a specific voltage not match another voltage no matter if the load is a light bulb or another power supply. A quick review of Kirchhoff's voltage and current law and voltage regulators will help you to understand what is going on when you parallel two power supplies.
BB
 

poltergeisty

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Toastedwaves

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It was more of a technical discussion about inner working fundamentals of chargers than simply buying more junk. Yes, sometimes these things take a couple of pages.
 

Toastedwaves

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I think that research and development is overall far more interesting, especially when there is a problem with what is available, like it is often the case nowadays. How many times did I buy something and even before using it once I had to modify it, seeing flaws in the design. If I can find/get one that exceeds my needs in amps, I would buy it, as experiments can be also frustrating and expensive.

I think I was clear enough about the buying online thing. It will not be an option for me at the present time. I will have to seek solution to that problem eventually, because that is where it's at.
 

OemUser

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"Beast"?...ok,.... if you say so...

Toshiba Satellite P850, also known as 'the beast'. Gaming laptop. Can eat most desktop for breakfast. Scary part is even the original charger is not quite up to it. :)


Please find attached; a link to a dual 330w PSU mod for a netbook (if the P850 is a beast, then these must be netbooks).

[Tutorial] Dual 330W AC Adapter Mod






submitted on my netbook: AW18, 4930mx overclocked, 32gb ram, GTX 780m sli, PM841 512gb msata ssd boot, 2x Crucial M500 960gb ssd Raid 0 storage, 330W ac adapter
 

Toastedwaves

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1. is the "40A 200V bridge rectifier (Mouser - Part #: 821-GBPC4002)" the "terminal bridge"?

2. Can you explain your choice of the terminal bridge rectifier model? Was your choice based upon the netbook demands in current only, or are there other specifications to consider?

All I want to do is give THE BEAST more amps :) because the chargers available here are too small. Not in V but in A.
 
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OemUser

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I have no knowledge of the rationale for the circuitry, nor did I have anything to do with the design or production of this circuit/mod.

Your questions would be best directed to the denizens of that site.

Be advised that they do not suffer fools graciously.

Leave the facade behind....and they will help you...
 

Toastedwaves

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Since they seem to be intelligent, I would think that being a moron with no sense of humor would be more of a problem for them. Heh, go figure.
 
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Toastedwaves, have you tried talking to someone in the store where you could purchase the inadequate adapter and see if they can order you one that has sufficient output? I mean they have to order them from somewhere and a sale is a sale.

Sent from my SAMSUNG-SGH-I337 using Tapatalk 2
 

Toastedwaves

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Yes good reasoning discombobulated, but it would take months to arrive IF there was not confusion and/or it didn't get stolen. I tried that from day 1, before this 'pursuit of knowledge' began.

These countries are not 3rd world for no reasons. Do not under estimate their stupidity, it is mind boggling at times here. They turn things that are inherently pleasant into something awful. Simple things into nightmares.

You've seen The Planet of the Apes, right? Well that is what's going on here. Now, ask them monkeys for a specific computer charger... They do however have coconuts here.
 

Toastedwaves

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I think that I'm gonna take pics of the hardware stores here, and be completely off topic, just to have a good laugh. That would remove any doubts about ordering the right part and hit page 5 in the process.. thinking thinking..
 

slicerwizard

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You just need two 5 amp low voltage diodes.

Code:
+ ---- --->|--- -----
                     \
                      ---- +
                     /
+ ---- --->|--- -----



- ----
      \
       ------------------- -
      /
- ----
They'll each dissipate less than two watts, so you don't need much, if any, heatsinking.

Next?
 

Toastedwaves

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Isn't those diodes reduce voltage output? I want to keep the current as is. I can reduce the amperage output, as I will have plenty of that with 2 chargers, but the voltage will have to stay 19v.

Thank you slicer!
 

slicerwizard

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The slight voltage drop (about 0.6V) is unlikely to cause any problems. I have some laptops and netbooks here; some use 19V adapters and others use 20V, yet I can mix and match adapters at will - 19V machines don't care if they're fed from a 20V adapter, nor do the 20V ones care if the adapter is only putting out 19V.

In the car, I simultaneously run a laptop and a netbook (one wants 19V, the other 20V) from the same adapter and the devices couldn't care less.

The "330W AC Adapter" mod also uses two diodes to isolate two AC adapters and the author's PC is obviously ok with the voltage drop.

You can use diodes with lower voltage drops (some go down to about 0.3V), but I would just try some common ones first.
 

Toastedwaves

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Gotcha. That's what I'll do!

Any particular "diodes" specifications/model you would go with?

I've used resistors to fabricate computer DEL lights, to reduce the voltage from 5v to 3v. Other than that.. :s
 
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