[Elecraft] Compact power supply

[Jim Wiley]

There have  been some inquiries about the small power supply /charger I 
found for the K2. Here is what I know:


The documentation that came with the unit was pretty sparse.  It was 
sold under the Velleman name, and was touted to be a "36 watt, Compact 
Switching Mode Universal DC Power Adapter" for notebooks and personal 
digital electronics. It has 20 selectable outputs, (5 to 24V in 1V 
steps),  with a max output of 4 amps.  The actual output rating depends 
on the output voltage selected, with the amperage decreasing as the 
voltage increases.  At 14 V, where I set my unit, the rated output was 
2.32 Amperes.  My unit will supply approximately 2.4 Amperes, above 
which  the regulator goes into shutdown mode, and the output drops to 
zero. It also runs on 100 to 240 Volts AC, with no input voltage 
preselection required.   There is a Velleman part number of PSSMV7U on 
the card. The UPC Code reads 836479006577.  The physical size (on the 
manufacturers bubble pack) is given as 30 X 45 X 90  millimeters.


I did a Google search and found several references, and one outfit, 
"Micro Center" offering them for about $45.00 plus shipping  ( I 
searched for hits that included the words Velleman and PSSMV7U).  Yeah - 
I paid a bit more ($65), but then again it was in stock at the local 
store, and I didn't have to wait or pay additional for shipping and 
handling.   BTW, a Google search on the UPC code number also produced 
some similar hits.


If you get one, you you will need to make sure that you plug in the cord 
end correctly, and the markings are not all that clear.  On either  side 
of the cord end is a + or - mark, and the tip has an arrow.  When the 
arrow points to the +, then the plug tip (center conductor) is 
positive,  and the shell (outer conductor) is negative.


I use lengths of  large diameter "un-shrunk" shrink tube for stowing the 
various cables while in transit.  This is an old trick, and probably not 
original with me.


The unit should be usable with any number of small portable electronic 
devices, including K1's and other small sets, as long as the power 
required fits within the unit's specifications.


- Jim, KL7CC