Tuesday, 27 December 2011

Homebrew 7" Touch Screen

(Touch monitor under test using Linux Mint)

I've posted a short set of photos of the LCD monitor conversion so far.


The monitor is one of a pair purchased on eBay for £15 (s0 say £8 per monitor) and the touch panel cost £14 again from an eBay store in the far east. Total cost is under £30 and a lot of fun in the research and modification.

The monitor is not VGA, but the picture is remarkably sharp and with big icons (such as Linpus or Tiny Core at 400 x 300 or something) this would be ideal as an in-vehicle dash control panel.

I've just ordered some panels (just the panels for now) for under £5 a panel. Now the electronics are the more expensive part, but I'm about to start looking at reading these resistive panels directly from a micro controller using A/D conversion.

More on that in the New Year.

Thursday, 15 December 2011


I thought this was pretty clever when I spotted it a while back passing a farm on the coast. They've put a row of solar water panels on an outbuilding roof. Nice south-facing roof too and low enough to make installation and maintenance a breeze. The only wonder is how the water is being piped from the outbuilding to the main house (if it even is). There's a fair loss in heat over even short distances which is why it is always recommended that solar panels are placed as close to the hot water tank as possible.

Still a great installation.

Tuesday, 6 December 2011

Large 4-digit LED display board

These are 1-inch green LED 7-segment displays I picked up on eBay. I got 8 in total for a few dollars. I wanted to use up some off-cuts of stripboard so I ended up sticking 2 pieces together using epoxy glue and a strip of scrap ABS plastic which is on the back. The DIL socket will hold a MAX7219 integrated circuit when the display is finished. The MAX7219 is an intelligent driver which can handle binary-coded decimal as well as bit-addressed data. I'm going to play about with this and add it to the ever-growing box of 'modules' for the car computer project (if ever...) as it would make a great rev counter or speedometer, or both.

LCD Monitors

Internals of the 6.2" LCD monitor. Just 4 connections needed, 2 for power and 2 for the composite video signal. Power connection is marked (strangely) 7v, but the power board supplied 9v and it seems to work on anything between 6 and 12v.

Internals of the 7" LCD monitor. The lower circuit board handles power and has a stereo audio amplifier.