Friday, 21 November 2014

eBay comes through

Sorry, this is a nerdy post.

We walked to Rugby this morning to buy a few items from the 99p and Poundland shops.  Whilst in the mall I went into Argos and asked about the eBay collection process.  The manager informed me that when the item is received in the shop eBay automatically sends the recipient an email with a collection reference code.

After making our purchases we wandered back to Brownsover for a slightly late lunch on Waiouru. I’d only just settled down to eat when an email arrived from eBay advising the Dc – Dc converter was available for collection at Argos.  Back into town I went.

This photo provides an indication of the size of the converter compared against my Leatherman

The following is a description of how I assembled the DC to DC step up converter.

I didn’t want the converter to rattle around inside the box.  Better to have it secured.  Rather than attempt to secure it inside the box I decided to mount it on the underside of the lid.

The machine screws and nuts were surplus to another small task completed last year and I don’t like to throw things away in case they are needed at some future date.  Yes… I’m a hoarder!  You might be able to see that each screw has two nuts on the bottom.  The purpose of the second nut is to act as a spacer thus enabling air to circulate under the converter printer circuit board.  You might have also noted that they are closer to one end than the other.  The reason for this will become apparent.

Washers were placed on top of the nuts and the converter fitted.  Another set of washers and nuts were then added to secure the converter to the lid.

The reason for the machine screws being offset is now apparent.  Additional room is required at the right end to allow for the cables being fitted into the terminals.  There is a very small brass screw at the opposite end (left arrow) The output voltage can be adjusted using a small jewellers screwdriver (99p shop).  The converter has two large heat sinks (the black components with fins).  Depending upon the required increase in voltage and the load (amps) the converter may generate significant heat.  This needs to be dissipated.

I marked a matrix on two sides of the box. and then drilled a series of holes to improve air circulation and dissipate any heat.

The input and output cable connections were then made and cable ties tightened on each cable.

The purpose of the cable tie is to reduce the possibility of the cable being ripped out of the terminals.  The last step was to connect the output plug to my multimeter and adjust the output voltage to 19.2V which is the required voltage for the laptop.

The lid was then screwed onto the base to complete the project.


Halfie said...

Very good - and at an amazing price! Have you checked how good the regulation is, i.e. have you checked the output voltage on load?

Tom and Jan said...

Hi Halfie
Of course. I wouldn't want to risk the laptop running on low voltage