Puakma: Under the hood

I'm Brendon Upson, jack-of-all-trades, master of one or two. I'm talking about life running a small ISV tackling business issues and leaping technology hurdles in a single bound.

webWise Network Consultants is based in Sydney, Australia and develops the groundbreaking Tornado Server technology.

Laptop LCD screen repair

Filed under: by Brendon Upson on 2006-02-08

My old Sony Vaio PCG-GRX3P (hell expensive when I bought it) has for the last few months experienced an intermittently faulty LCD backlight. A couple of weeks ago I decided to get it repaired so sent it in to my local Sony repairer. Nearly fell off my chair when I got the quote for 770 dollars (which I had to pay 99 dollars for) for an entire new LCD panel. At that price it is not feasible to repair - the laptop is about 4 years old and other components will be likely going to the big electronic graveyard in the sky soon. For under 1000 dollars you can now get a pretty good brand new laptop.

So. I decided to do some research on possible problems with the screen. I was fairly sure the screen was OK because only the backlight goes on and off. Research indicated it was most likely a) the backlight b) the inverter c) a connection between. Knowing the backlight does work sometimes, I was sure the backlight was OK. The backlight is essentially a tiny fluoro light, so I reckon if it was dead we'd get nothing - no intermittent blink. That narrowed the field to inverter or connection. My money was on the inverter.

At this point I did what all good nerds do and dismantled the screen into pieces so I could see what I was dealing with. To my surprise when I messed about with the inverter and shorted a couple of bits out the screen came to life (BIG WARNING: DO NOT DO THIS UNLESS YOU HAVE A VAGUE CLUE WHAT YOU ARE DOING. YOU WILL DIE. Inverters have an output to the CCFL (backlight) of between 700-1000 volts. This is enough to kill you until you're dead). So I was now 90% sure the inverter was the issue.

Jumped on to ebay and searched for the part number on the inverter. Presto. A company in Chicago USA was selling one for 25 USD. Ordered. Done. Wait about a week for delivery.

It arrived today and I popped it into the LCD panel. Worked perfectly. Total time to install and reassemble, about 10 minutes. Total cost 38USD. Plus of course the 99 dollars it cost to get a quote for the replacement of a part that was not broken. Think I might write them a nasty letter.

The Model View Controller Model (MVC)

Filed under: by Brendon Upson on 2006-02-08

MVC is the architecture espoused by all and sundry as the epitome of "proper" development. Conceptually it makes sense. The reality falls a little short.

We were discussing the relaitve merits of different application servers here at WNC the other day and discovered that although we strive to separate the visual stuff from the business logic, there is always some overlap. J2EE, as an example, has JSPs and servlets as the main two application design components. The servlet is normally used for logic and heavy lifting (let's not talk about EJBs in this context, as few people actually use them) while the JSP provides the visual layout. Problem is you can poke layout into servlets and (more dangerously) you can poke logic into JSPs.

I've never been a fan of JSPs purely because the ugly mix of html markup and Java code all in the same file. For this reason we went with p-tags in pages in Tornado server. The p-tag simply denotes a field you have no ability to put any kind of server-side logic into Pages. Actions are a little less clear and are most like servlets (or web query open agents in Domino). In Actions there is the ability to blur the line between presentation and logic.

It's all about compromise. I think we strive for perfection but always have to compromise at some point between delivering the solution and coming up with the perfect logical design. The difference between a good and bad system is where that compromise point occurs.