Wednesday, 11 January 2017

Back to Merry Hill

The weather looked cloudy but dry so we decided to cruise the reasonably short distance to Merry Hill where Jan wanted to visit a number of shops in the large InTu Retail Mall.  Of course it decided to rain quite hard during the cruise leaving me rather drenched by the time we reached Merry Hill.  I did try increasing the speed but the canal is rather shallow in places and I ended up catching urban jellyfish (plastic bags) on the prop.

There were only two moored boats when we arrived, one being NB AreandAre with Barry on board.  After a conversation and hot drink with Barry he headed off towards Bumble Hole retracing our route.  However, unlike our trip it looked like he wouldn’t be caught in the rain.

Jan had a rather fruitless trip to the mall discovering none of the shops had what she wanted. 

Jan here…… There was little chance to look in the shops because I was dragged around as if we were doing the Indi 500

I noticed the laptop wasn’t charging when plugged into the boat 12V system.  I’ve previously assembled a DC to DC step up converter which raises the boat 12V to the laptop 19.2V.  The converter appeared to be working as the small red LED was illuminated and I was getting a 12V reading with the multimeter.  My first assumption was there was a fault with the 12V boat socket.  That proved to be incorrect.  Then I realised the converter output was 12V instead of 19V.  Our cheap ( £2.52) Chinese circuit board had failed.  The laptop has been permanently connected to the boat 12V system for several weeks and I therefore shouldn’t be too surprised that a component on the board has failed.  We’ll need a replacement board.  After examining the board I realised the heat sinks might prove useful.


The heat sinks are the two black painted aluminium plates with fins.  They look about the right size to fit on top of a Raspberry Pi cpu.  The Raspberry Pi does get hot and you can buy an aluminium heat sink for the cpu.  But why buy something when you can salvage one.  I filed the solder joints off the base of the printed circuit board and unscrewed the connection to the board to recover two free heatsinks.

P1030662Finally I must acknowledge some recent blog comments from readers haven’t been published.  For some reason Blogger thought they were spam.  I hadn’t realised this had occurred because I don’t directly use Blogger.  All the blog posts are written using Open Live Writer and we are supposed to be notified by email if a Reader leaves a comment.   I don’t know why Blogger decided some Reader comments were spam and it now appears I’ll have to regularly check Blogger rather than relying on the email advice system.  


Halfie said...

Hi Tom, I have been using the same DC - DC converter for our laptop. This worked fine for a few weeks, despite running quite hot when the laptop's battery was low. Then it failed like yours, so I bought a replacement. Despite setting the output voltage to the required 19V the laptop didn't like it and refused to charge. The converter still puts out the right voltage, so I don't know why it doesn't work. Perhaps I ought to try more smoothing, a job for when we resume cruising in the spring.

Tom and Jan said...

Hi Halfie

The converter for the TV is still working after four years. But there isn't much of an increase in voltage on that power supply. The laptop converter worked well for two years when I was only using it to recharge the battery rather than leaving it permanently connected. Recently I've been doing a large amount of work on the laptop, sometimes leaving it running on the converter for 24 hours and I think this overstressed the converter.