Archive for the ‘hardware’ Category

Recording and Archiving TV Is Still Not Simple

January 2, 2010

We have Comcast cable TV with a digital tuner box that contains a hard drive to support video recording. When its hard drive filled up with shows we wanted to watch in the future, I had to figure out how to save them somewhere else to free up disk space for new recordings. As I pondered how to do it, I thought back a few decades and wondered why this process can still be cumbersome, given the improvements in technology….

In the 1970s, it became possible to record shows from your TV for viewing later, using a video cassette recorder (VCR). This is called time-shifting, and was ruled to be legal by the U.S. Supreme Court in the infamous 1984 “Betamax case”.

Doing this required learning how to program your VCR using its primitive interface and looking up show times on a printed TV schedule in a newspaper or TV Guide magazine. You could archive the shows you wanted to watch later by storing the video tapes.

In 1999, TiVo introduced a hard disk based digital video recorder (DVR), which downloaded the TV guide over a phone line or (later) the Internet. This let you choose shows to record by name; TiVo even records shows it thought you might like. For archiving, hobbyists figured out ways to get the recorded MPEG2 video files off of the TiVo’s hard drive and onto a home computer’s hard drive, where they could then be stored, viewed on a computer, burned onto DVDs, or converted into other formats such as MPEG4.

That was a great arrangement, but the TiVo boxes cost several hundred dollars plus a recurring subscription fee for the guides, and TiVo gradually made them harder to hack into to get the video files. The cable TV companies (like Comcast) started offering their own, simpler DVR boxes for cheaper (just the monthly fee). Our is made by Motorola. It has some computer connectors on the back, like Firewire, which aren’t enabled by the Comcast software on it.

So, how to copy shows off of the Comcast DVR? It’s ridiculous, but I have to record the shows in real-time into a computer. I got a Canopus ADVC-110 DV capture card that connects by Firewire to a Mac laptop running Final Cut Express, and by S-Video and RCA audio to the Comcast DVR. After I capture each show from the Comcast DVR into FCE, I trim out the commercials (replacing them with chapter markers), black out the in-frame ads for other shows with cropped slugs, de-letterbox by zooming if applicable, and save it as a QuickTime DV file that I can re-encode into MPEG2 for a DVD. There’s no good technical reason for these extra steps, just corporate politics.

I also use the Canopus to capture video from VHS tapes and analog camcorders, so I needed it anyway; I didn’t get it just to save shows from the DVR. Otherwise, I might have considered getting a TiVo and a CableCard. Other possible capture devices include:

  • A standalone DVD recorder to skip the re-encoding step, but that wouldn’t let me cleanly edit out commercials or re-encode for viewing on computers or portable devices.
  • For smaller captured file sizes, a capture device that encodes in MPEG4 instead of DV, such as the Elgato Video Capture. That would mean editing out the commercials using QuickTime Pro 7 or MPEG Streamclip, instead of Final Cut or iMovie. I find the Final Cut interface easiest to use and it gives me the most power in editing.
  • To capture HD, I’d have to use something with component video inputs like the Blackmagic Intensity Pro PCI-e card, but I don’t have a Mac with PCI-e slots near my TV. Or the Hauppauge HD PVR, which encodes in AVCHD format, which I would need to decompress to edit. And HD video uses even more disk space. Someone else has written up a procedure to convert HD video captured by a Hauppauge HD PVR into a standard-def DVD, for those who want to try that.

Putting the Power Back in PowerBook

December 20, 2009

My PowerBook G4 (17″, 1GHz) was having more and more problems charging its battery. More often than not, when I plugged it into AC while turned on, it would flip back and forth every couple of seconds between showing it was plugged in and showing it was running off battery, with the screen brightening and dimming each time, and making a loud whining noise. It got to where I usually had to put it in sleep mode or turned off in order to charge the battery. The battery wasn’t the problem; it was a new replacement battery that worked fine in an identical PowerBook.

Some searching turned up a web page claiming to describe a fix for this problem.

The author of the article describes symptoms like I was seeing and attributes the problem to Apple’s power connector design, which gradually wears out. He describes how to replace the PowerBook’s power jack and the power supply’s plug with generic power connectors from Radio Shack. I decided it was my only option for trying to get my laptop working reliably again, so I tried it.

The article’s author has a 15″ model, which is disassembled differently than my 17″, so I had to adapt the instructions. I used the following guide from iFixit.com: Installing PowerBook G4 Aluminum 17″ 1-1.67 GHz RJ-11 Board. I used a size N DC power plug and jack, Radio Shack part numbers 274-1583 and 274-1573, and they fit well, with no extra washers needed.

It works! My PowerBook now charges while turned on and doesn’t emit a loud whine when plugged in.

I never thought I’d be hacking laptop hardware, but having someone blaze the trail gave me the courage.

PowerBook G4 replacement power jack, inside view

PowerBook G4 with replacement power jack

The Computer Museum Moved and I Didn’t Notice

August 5, 2008

In the early 1990s I was working as a programmer for the Free Software Foundation, mostly remotely from Maryland but I’d go up to Cambridge, MA for a week every so often to work face to face with people. One highlight from those trips was visiting the Computer Museum. Besides the exhibits, one thing I enjoyed was in a side room they had a Sun workstation you could see through a window. I’m not sure what it did, either helped run exhibits or provide networking for the staff. When I was there, the screen was in text mode scrolling, I think, “le0: No carrier”. So I felt right at home; it was just like at the University of Maryland.

Around the middle of the museum was the exhibit on computers of the 1980s, which had an endless loop of part of MC Hammer’s “U Can’t Touch This” playing through a speaker to set the mood. If you started to get disoriented in the exhibits, you could just head toward the rap music to find your bearings.

In October, 2006 I went back to the Boston area for my brother’s wedding, and found that the Computer Museum doesn’t exist any more. Some of its exhibits are in the Boston Museum of Science next to the Hall of Electricity. That includes parts of a huge mock-up PC. My wife took my picture standing in front of a giant Adaptec AHA-2940 SCSI controller card on the wall. I still had a couple of those cards then; one was in a Linux PC driving a Plextor CD-ROM which I used for digital audio extraction until I switched mainly to a Mac in January, 2006.

Then I stumbled on a video of an hour-long talk of recollections by Woz:

It was posted by the Computer History Museum, and the introducer, Len Shustick, says “I’m always surprised at the number of people who knew about the Computer Museum in Boston… and who don’t know that it no longer exists…. We are its reincarnation, and starting in 1996 we filled up tractor trailers and moved them west….” I provide anecdotal support for that comment!

It’s interesting that they reopened in Mountain View, CA, where I worked the next summer in 1993 at Cygnus after my time with the FSF.