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3 Down News – New CFL iPhone App Now Available in App Store

July 1st, 2010 Comments off

July 1, 2010
Ottawa, Ontario

New to the App Store, 3 Down News is the only App available that provides CFL fans with tailored, constantly updated news from the top traditional and new media sources from across Canada.

3 Down News provides up to the minute news for each team, with sources including newspapers, blogs, YouTube, Flickr, as well as in-app streaming audio for game day listening.

3 Down News is now available for $0.99 in the App Store.

For more details, screenshots, blog and twitter feeds visit:
http://kje.ca/3downnews

Direct iTunes link:
http://itunes.apple.com/us/app/3-down-news/id378669280

For more information please contact Ken Edwards at ken@kje.ca

Categories: Tech

RCA Over Cat5

November 4th, 2007 No comments

I spend a lot of time in my kitchen, cooking up some hopefully tasty creations. With our recent move, our kitchen was upgraded considerably. In the apartment, I could hear the TV and even watch it, albeit at a viewing angle approaching 180 degrees. In our new place, the TV in the living room isn’t visible from the kitchen, and I was getting lonely and bored cooking while the TV was on in the other room.

Our New KitchenOur recent subscription to Rogers’ Digital VIP pack includes a SD digital box that we weren’t going to use in the living room. So we, and by ‘we’ I mean ‘I’, decided to buy a small TV and mount it on a wall in the kitchen. The only problem is that if you look closely at this picture, there is no cable outlet in the kitchen. There is, however, a Cat5 drop here, running from the ground floor.

WiresMoving down to the ground floor, we find the utility room that houses our washer & dryer, furnace, and hot water tank. This is also the room where the cable and phone lines come in from the outside, so our cable modem and wireless router live here too. It’s a big mess right now, but clean-up is on the low-priority to-do list, and I’m not too keen on spending too much on making this room pretty, especially since we are renting.

After some research, and a failed attempt at just soldering the RCA wires to the Cat5 twisted pairs (Yes, I knew there is an impedance mismatch, I just wanted to see for myself), I went to Home Depot and they had what I was looking for:

What these do is let you use one twisted pair to send one of the three RCA signals, yellow for video, red and white for audio, over one twisted pair of Cat5 cable. There are 4 twisted pairs in one Cat5 cable, so you can use 3 for the RCA signals and have one to spare, which you can run a telephone over if you wish. They were about $5 each, and I needed 6, 3 for each end. Perfect for my situation!

The 40735-R*W units come with everything you need to get them attached to your Cat5, so other than something to strip the twisted pair wires inside the Cat5 cable, you don’t need anything special to get this working.

So in the basement, we have the cable box, RCA wires, and the QuickPort connectors:

There were 3 Cat5 wires there, going to the master bedroom, the guest bedroom, and the kitchen. To figure out which one to use, I guessed. Got it right the first time. =)

So on we move to the kitchen. It’s the same process, plug some Cat5 into the wall socket, slice off one end and put on some more of my favourite new connectors:

I picked up a 19″ LCD TV, a Sharp LC-19SB24U. It has a really thin bezel, which makes it look quite sleek in the kitchen. To mount it to the wall, I picked up a mount (00K79.21) at the Lee Valley showroom / warehouse here in Ottawa. I found out that Lee Valley has some great prices on these from my favourite home-theatre forum: Digital Home Canada.

I decided to put it on the wall where you see it so that I can put it out of the way when I don’t want the LCD close the kitchen work area. Here it is mounted to the wall:

So it all worked out pretty well. Here are some shots with the TV in the cooking position and in the safe at home position:

So at this point in time there are a couple of things left to do here, clean up the wires, and implement some sort of IR transmission system so I don’t have to walk down to the laundry room every time I want to change channels!

The last picture I have is of the wire management package that I picked up at Home Depot. I just need to pick up a white Cat5 cable to run from the wall up to the back of the TV:

So, it’s been a fun project… and now I can watch Sportscentre in the morning making breakfast and the Habs while making dinner =). If you have any comments, let me know at ken@kje.ca.

Categories: Tech

MATLAB Vectorization

March 19th, 2007 No comments

After reading up on MATLAB vectorization last week, I wrote this code to normalize each row of a N by 3 matrix. The speedup is not enourmous, but it is significant. I tried timming things this weekend on my computer at home, but MATLAB on a 1GHz G4 with 512MB of RAM is not what you would call ‘peppy’. I’ll try on a modeling workstation at the office today and see what’s what when we try a big matrix and it can stay all in memory.

function [ ] = unit_vector_rows_for( N )
%UNTITLED1 Summary of this function goes here
% Detailed explanation goes here

%make a 1×3 matrix, we will consider rows as 3-tuples
a = [1:3] ;

%repeat a so that it becomes a N by 3 matrix, so we can have a big one to
%test

a=repmat(a,N,1);

tic
for i=1:size(a,1)
a(i,:) = a(i,:) ./ norm(a(i,:)) ;
end
k=toc;
fprintf(‘For loop time is %f\n’,k);

function [ ] = unit_vector_rows_mat( N )
%UNTITLED1 Summary of this function goes here
% Detailed explanation goes here

a=[];

%make a 1×3 matrix, we will consider rows as 3-tuples
a = [1:3] ;

%repeat a so that it becomes a N by 3 matrix, so we can have a big one to
%test
a=repmat(a,N,1);
tic
a = a./repmat(sqrt(sum((a.^2)’))’,1,3);
k = toc;
fprintf(‘Vectorized time is %f\n’,k);

Categories: Tech