In article ,
 Martin Gregorie  writes:
> On Wed, 09 Jan 2019 13:07:38 -0500, Dennis Lee Bieber wrote:
>
>> On Wed, 09 Jan 2019 13:05:13 +1300,
>> nospam.Vince.Coen@f1.n250.z2.binkp.net (Vince Coen) declaimed the
>> following:
>>
>>>I have decided touse a laptop ps that gives 19v at 3.43w and hopefully
>>>can even use it to power the Pi as well - have to look when the kit
>>>arrives from Singapore in 10 - 20 days.
>>>
>>  You're going to need some sort of voltage regulation to drop that
> 19V
>> down to a level most equipment wants. The input of the R-Pi is 5V (as
>> are the BeagleBone Black, Arduinos, TIVAs, etc.). Going much above those
>> levels will either damage the board, or cause very hot running if they
>> have on-board regulation.
>>
>>>The drive is one of a few spare 1 Tb among many others so I do wish to
>>>make use of one or more and not use a USB external which I use for back
>>>ups only.
>>
>>  I suspect most "full size" drives are either 12V or 5V (probably
>> depending upon connector). A "Best Buy" drive enclosure I have uses
>> 12V@2A wall wart barrel jack and a USB-3 connector for data (not power).
>> .
>
> Solid state converters are easy to find on eBay.
>
> For years I drove the PNA (Personal Navigational Assistant, or pocket
> satnav) in my glider off the sort you used to find that fit the cigarette
> lighter in a car. When that failed after 10 years or so I picked up a
> much meatier unit off eBay (12-22v in, 5v out at up to 3A) which works
> just fine.
>
> There are lots of these on eBay for under GBP 5, some already fitted with
> a USB 2 socket and some advertising themselves a perfect for driving an
> RPi. The ones without a USB socket all have decent, thick wire on the
> output side.
>
> Apparently they were originally sold to power the LEDs 'da kidz' liked to
> decorate their cars with.

I've used car/truck cigarette lighter adaptors for years.
Usually, I pull out the guts and put it in my case with the Pi.
The truck ones are 12-24V input.

More recently, I tried some cheap DC DC buck converters from Amazon/Ebay.
They work, but they generate so much RF noise the WiFi was unable to
work on the Pi. None had any output filtering other than just the single
electrolytic capacitor. Even with adding some filtering, I couldn't get
WiFi working. Went back to a car cigarette lighter adaptor, which works
fine. (A friend told me some of the car adaptors have bad RF radiation
too - he used them in a glider to power a GPS, and you would get the odd
bad one which killed the GPS signal.)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

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