[SGVHAK] recommendations for bench power supply

[Matthew Campbell]

My big supplies (lots of volts and lots of amps) were picked up at C&H
before they closed.  Lab grade but old enough they were not worth
certifying again.  Awesome deals at <$50 for >$1000 supplies.

Smaller supplies for desktop embedded work are easy and cheap to make
<$10 and make great learning to solder/perfboard projects.  The
circuit is terribly simple ( a couple of caps and a voltage regulator
able to handle line input or a step-down and smaller regulator.  Don't
forget to heatsink any high wattage components and you're golden.  The
cheap regulators do a fine job and the variable ones can be made into
a simple multi-voltage source using a multi-way switch (3v, 5v, 12v,
variable) and a pot for the variable.  Drop the right resistor off
each leg of the switch and you have simple selection for your
projects.  Hang a cheap ($10-$25) digital meter and you have a fully
functional multi-voltage bench power supply for ~$30.  A good case
will set you back more.

Lan, if you want to do a bench supply workshop I can help lead with
some lead time.  Dave would need to be tapped to keep me honest!

Matt

---------
Matthew Campbell
Storage and Cloud Strategy
Office of the CTO

Kaiser Permanente
99 S. Oakland
Pasadena, CA 91101

626-564-7228 (office)
8-338-7228 (tie-line)
818-314-9897 (mobile phone)
Green Center 3-North, 031W29
---------
kp.org/thrive


On Sat, Mar 12, 2016 at 9:42 AM, Braddock Gaskill <braddock at braddock.com> wrote:
> I bought a ps1503sbu bench supply a few years ago.  Pretty small, cheap
> (~$80) and basic.  Got it at Fry's if I recall.
>
> http://www.amazon.com/Velleman-PS1503SBU-Digital-Display-Backlight/dp/B000I3X7Z4
>
> On Mar 12, 2016 9:32 AM, "Lan Dang via HAK" <hak at sgvhak.net> wrote:
>>
>> Hi all,
>>
>> What would you recommend for an portable bench power supply for a novice
>> mostly playing around with Arduinos?  I was inspired by our recent session
>> at Tux-Lab examining old electronic components, where we were able to hook
>> LEDs directly to the power supply because we could control the current.
>>
>>
>> I thought it would be nice to add this piece of equipment to the stuff I
>> normally carry around to HAK meetings and Repair Cafe--hence needing it to
>> be portable, as well.
>>
>> I'd like to buy one before our next Repair Cafe/Saturday HAK meeting.
>>
>> Recommendations please.
>>
>>
>> Thanks,
>>
>> Lan
>>
>