The Perceptus Back Story

My Inspiron 1525 has intermittently not been charging while plugged in. It’s gotten worse, as many intermittent problems tend to do. So, it was time for a bit of research.

It’s intermittent, so the charger generally works. I do have some battery life when it’s charged, so the charging circuits and the battery do work, though, this two year old battery doesn’t hold much power anymore.

If you search the web, it turns out to be a relatively common problem – remember, Dell sold millions of these laptops, you would expect a few problems to be reported. This laptop power connector consists of a pin in the centre of a circular connector which itself has two metal contacts, one on the inside and one on the outside of the circular ring. The inside pin is used to identify the A/C adaptor as being an authentic Dell charger. If the centre pin does not make contact with the socket on the laptop, then it will not charge; however, it will still work while plugged in.

A couple references:

- http://www.laptop-junction.com/toast/content/inside-dell-ac-power-adapter-mystery-revealed
– http://www.tomshardware.com/forum/9519-2-dell-laptop-power-jack-pinout

So, I ever so slightly bent the inside pin to the side so that it would make contact again, and it seems to be working. I’ll wonder how long it will last though.

Given how often I move my laptop around, I think it was just general wear and tear rather than a manufacturing problem. Though, I wonder if there was a legitimate purpose to the identification pin. Can an non-authentic Dell power brick really damage the battery charging circuits, while still being OK to power the laptop in “plugged in” mode?

[Edit: Hmm... upon reading some more about this, new laptops might need a way to communicate with the power brick to determine maximum power output.  If the maximum output of the transformer is too low, then the laptop can skip the battery charging to keep total power consumption down.  This also would be useful in "airplane" mode where there is a very limited amount of power from the outlet.]

Anyway, I’ve had a very similar problem happen with a cellphone charger a couple years back, so the fix wasn’t all that unique. Let’s hope that someday we can all have magnetic power connectors like the Apple guys…

I’m about to rant about our local cable internet provider, Shaw’s, mediocre email. Their hit-and-miss SPAM filters decided to block an email newsletter that I manage for a local retailer. I hate it when that happens. Shaw.ca email addresses are about 25% of the list, so when they block a message, I know. And it makes my numbers look bad.

When picking an email address, you have three general options:

What should you use?

I strongly recommend that you use a webmail provider. Especially Google’s Gmail.com. However, Microsoft’s Hotmail.com and Yahoo’s Mail are satisfactory too, certainly better than your ISP.

Why?

The proof is in the pudding. Most people don’t maintain an email address at major email providers for testing purposes. I do. The test shaw.ca email address is full of opt-in email newsletters that have been misfiled as SPAM. Including the occasional one that is managed by me.

There will probably be more posts regarding email newsletters, particularly ones in BC and Alberta. It’s something I deal with a lot, and it’s about time I share some tidbits.

Today we updated print-bingo.com’s programming.

The biggest fix, is that our site now works properly in current versions of Google Chrome. Our web based system for generating highly printable bingo cards is great… but once in a while we run into compatibility issues. For now, it’s fixed. We’ve tested in current Firefox, Internet Explorer, Google Chrome, and Apple Safari web browsers. Ironically, part of the programming fix was related to a compatibility tweak for Mozilla browser from years back. Mozilla users, if you actually still exist, you will need to use a different browser to use print-bingo.com now.

At the same time, we made live a feature that we wrote for a custom bingo job a few months back. All bingo cards within a single run are now guaranteed to be unique. Previously, it was entirely random if a card was duplicated in a run – but it was highly, highly, unlikely. In fact, we programmed an email notification if the dupe-tester actually catches a dupe.

We had to hard-code a duplicate entry to actually make sure the dupe tester and the email notifier worked. The odds of duplicate cards that are randomly generated is extremely low – you can’t generalize exact odds, since every custom bingo card design is different.

The site has probably generated 1,000 card runs since the new code went live… and we haven’t been notified of a duplicate card yet. If we ever catch a dupe, we’ll be sure to post about it.

More code changes are on the way. It’s summer, traffic to print-bingo.com is lower than normal.

First note, for Canadians: Happy Canada Day! Unfortunately, we have forgotten to create a custom word list for our own country’s birthday. It’s a bit too late to do it this year, but our Canadian Provinces and Capitals word list is a reasonable place to start.

For our American friends, the Fourth of July is just around the corner! It’s a great day for family to get together… and maybe play a little 4th of July themed bingo?

As always, basic use of print-bingo.com is free. We have hundreds of people using the site every day that way. But we reserve a few features for people who upgrade for the excellent price of $10.

Happy Birthday!

Today, I learned more about Windows 7 and it’s built in software disk mirroring for hard drives than I ever wanted to know.

It’s virtually impossible to find this listed on an official Microsoft.com page (I can’t find it), but Windows 7 Professional has software disk mirroring enabled. In previous versions of Windows, software disk redundancy was limited to the server class operating systems, e.g. Windows 2000 Server, Windows 2003, and Windows 2008. Although, IIRC, Windows NT4 Workstation had disk mirroring, but I’m too lazy to look that up.

I spent several minutes today trying to find an official page that listed software RAID as a feature… and failed. Then, before starting this post, I tried again, and still failed. There are several 3rd party sites that mention software RAID being enabled in Win7. In the end, I had to set it up myself to be satisfied that it was true.

No, dynamic disk mirrors are not really the same as RAID1, but it’s close enough for me, and better in some ways – it should be possible to move a Windows mirrored drive to a completely different motherboard, for instance.

BTW, be careful with the entry level Dell Vostro 230′s, they don’t include support for Intel Matrix Storage anymore! Yes, that’s how this whole exercise started.

P.S. I just noticed that this is blog post number 101!