About Mike Pfaiffer

Posts by Mike Pfaiffer:

May 14 2012

SATA tip:

Regular readers will know I’m into DIY and fixing things. Lately my Linux PC has been having some hardware problems (which is why people haven’t been seeing a lot of regular posts from me lately). It’s been going on for some time in fact. I’ve checked out a lot of potential hardware issues and ended up replacing most of the computer at one point or another. One thing I haven’t checked out is the SATA cables. Last Friday I borrowed a couple from the place where I volunteer. I removed one cable and replaced it with the one I borrowed. The speed increased as soon as I turned on the machine. However in order to remove the cable from the motherboard I had to remove the other three. Apparently I didn’t put the first two back in the same plugs where they were originally. The computer couldn’t find the boot drive. After a quick switch of the first two cables things worked again.

The lesson here is when replacing SATA cables, make sure they go back into the same place.

By BlankMike • Uncategorized • 0

Mar 5 2012

Booting from IDE drive when there are SATA drives

This is a generic sort of article… I have only tried it on one type of machine but this advice may prove useful in other situations.

As regular readers know, I volunteer at an educational non-profit organisation every Friday as a systems administrator.One of the privileges is I get to borrow a computer every so often for one of my projects. In this case I had a computer I was using as a file server (using FreeNAS v7.x). Since I had it for over three years I figured it was time to get something a little newer. A client returned a Dell GX 270 because he no longer needed it. I asked and was granted permission to replace the older machine with this one.

At first I only had two hard drives to work with. The first was the hard drive from the old computer and the second was the drive from the new one. I was able to boot from the old drive with no problem. Adding in the new drive so it would be accessed over my LAN was also easy. I had a third drive. It was a 500GB SATA drive. I had everything but the power adapter so it took a few days to connect.

The SATA drive was one I had in my Linux box before the motherboard died. It still had all the information as well as the master boot record intact. Once it was added into the 270 it wanted to take over. Like Macs there is an option which allows the user to select which drive to boot from. For a file server that’s not an acceptable solution. In this case it didn’t work very well either. The boot process was hung for 15 minutes…

After a bit of research on the net I found the solution was to boot from a rescue CD/DVD and toggle the bootable flag on the first partition on the hard drive to off. From that point things worked fine. I don’t know if the hard drive works or not since it was only yesterday I added it to the machine. Assuming there are no hardware problems I should be able to do a bunch of neat things like create virtual machines which are stored on  the LAN, set up a private iTunes server, and back up the Mini I am using at the moment…

By BlankMike • Disk Images, Disk Storage, Emulation, File Utilities, Freeware, Hardware, Public Domain, Software, Virtual Servers • 0

Feb 16 2012

TV tuner and a DIY antenna

It’s going to take a while to get to the computer related material in this article. Please be patient.

Ever since I was a little kid I’ve been curious about the world around me. I was the type of kid who wanted to see what was on the next block or figure out how dolls were made (yes I took them apart and put them back together again). The only time I got into trouble for it was when a big kid thought he was doing the neighbourhood parents a favour and told us little kids not to go near the river because there was a big monster there. We wouldn’t have gone there anyhow but we really wanted to see that monster. We were so disappointed we told our parents. I didn’t see why they were so upset. We made sure not to go near the river. We stayed a whole six inches away from the water. ;-)

Later I wanted to figure out as much as I could about radio and TV. I used to lay awake for a couple of hours per night listening to short wave and AM just to see how far away the stations I could pick up were. As I recall, the name of the hobby was called DXing. I was able to get stations from South Africa and Moscow on short wave and as far south as the American gulf coast on AM. Now all I can get on short wave is Radio Cuba and American religious stations. TV was similar. When I wanted to see what was available over the air we only had three Canadian stations and one American station. With the switch to digital (many years later) I found we had six Canadian stations and (depending on location) one American station. Actually we have cable in the house and I am satisfied with it. It’s just that I’m still curious about what I can get locally.

I mentioned this to a friend at a local computer club and he suggested I connect my cheap LCD TV to an external antenna. I had previously connected it to our old VHF antenna and was pulling in five of the six Canadian channels. The American channel was a lost cause. He pointed me to the “coat hanger” antenna plans at Make magazine (it’s a DIY magazine like popular mechanics used to be). After reading the description I found it to be a UHF antenna. This was fine for me since four of the local stations were now on UHF (including the one I couldn’t get earlier). The other two Canadian stations and the American station were on VHF-High. I built the antenna and had some interesting observations. In the basement I was able to get two stations. That makes sense because UHF frequencies are basically line of sight. On the ground floor of a house covered in stucco (which filters out some signals) I was able to get all four UHF stations (including the one I couldn’t get before) and one of the VHF stations. The quality of the signal also improved since there were less “drop outs”. After a bit of research I found line of sight improves as the height of the antenna increases.

Not being satisfied I did a bit more research. First off, TVfool.com (a list of TV signals theoretically available in a given area) showed there were additional stations just beyond the horizon. On a good day before the digital conversion we used to be able to pick up two of them when the signals bounced off the troposphere. Apparently there are another three or four more in the area. Then there was video of one guy who lives slightly North of me being able to pick up Minnesota stations. This was a shock because North Dakota is directly to our South and much closer. It was about that time when I discovered plans for the Grey-Hoverman antenna (released under the GPL3). Apparently this antenna is so sensitive it puts the coat hanger antenna to shame.

While I was out shopping for material to build the new antenna I was talking with a sales person and a TV engineer I met at an auto supply place. They both decided to give it a try themselves earlier than I had. One of them was using a TV tuner card on their PC with the four inch antenna that came included in the box. The other guy had an expensive TV with a cheap commercial antenna (he was opposed to cable and satellite TV on principal). Their experiences were strange. Apparently neither were satisfied with expensive commercial antennas and found the cheap ones were just as good if not better for their needs. Both were able to pick up all the stations in town as well as the American channel. I told them what I was looking to do and I was looking to spend $10.00. They said for that price it was worth giving it a try.

At the moment the build for the Grey-Hoverman antenna is stalled due to a cold.

Here is the computer related part. Another computer club was looking for a presentation last month. I figured since I had the coat hanger antenna we could look at a TV tuner card. A member of the club has a friend who works at a local computer store and he asked me if he could help. I suggested he see if he could borrow a cheap $50.00 digital tuner card. The store loaned us the top of the line $250.00 card for the meeting (Thank you MyMacDealer for the free loan). On the day of the meeting I realised the building was of a cinder block and rebar type construction. It also had lots of steel heating ducts and such. Essentially this meant it was worse than my house for getting signals. Plus we were also meeting in a room smack dab in the center of the basement. The package didn’t come with the four inch antenna I anticipated. It didn’t come with any antenna at all. I had my doubts it would work. Without an antenna there was no signal at all. With the coat hanger antenna it brought in one strong and one weak signal. Much better than expected. I showed the plans for the coat hanger antenna to an engineer as well as a city technologist. They thought the design was very ingenious. A couple twists here and there introduced some noise cancellation features. According to what they said the coat hanger antenna performed much better than expected.

Once I build and test the Grey-Hoverman antenna I’ll approach the other group and see if they want to do a live demonstration of Myth-TV. This way they can test the two antennas side by side. They will be using a different tuner card. The one for the Mac had a single tuner and connected to the USB port. The one these guys use has two tuners and is an internal PC card. The cost of this particular card is about $150.00. Boiled down to the nitty gritty… The TV tuner cards work. If it doesn’t then return it and try a different model.

Some DIY stuff… The construction method I used with the coat hanger antenna was pretty shoddy. Further reading suggests it is really hard to go wrong with this one. Just make sure the wires are not touching when the connecting elements cross (insulated wire is a good choice here). The coat hangers should be scuffed so as to remove any paint and rust so they can come in contact with the connecting elements.

For the Grey-Hovermann antenna it is best to build a jig for bending the wires to the correct angle and cutting them to the correct length.

If anyone is looking for increased sensitivity and distance, connecting two identical antennas together will work. However anything more than a dual bay (two antennas) results in diminishing returns and isn’t worth the effort.

It is possible to angle both antennas in a dual bay differently. However if they are at a 90 degree angle the signals cancel out.

Reflectors can increase the sensitivity up to 30% but turn the antenna into a directional antenna.

Using wood as a mounting material means the antenna is designed for indoor purposes only. Outdoor antennas are typically mounted to PVC or insulated metal.

Outdoor antennas need to be grounded.

For the most part for a basic antenna, scrap material can be used for minimal cost. Using better quality materials and better construction methods will improve the output somewhat.

As a radio tech friend once told me. “All you need to get a signal is a long enough piece of wire. Anything else is just getting fancy.”

By BlankMike • Design, Do it yourself, Documentation, Hardware • 0 • Tags: , ,

Jan 24 2012

E-book reader and translator

I’ve discovered something surprising. There are many E-book readers for the Mac and only one for Linux. This is a shocker. Ideally, with a few changes, those Mac readers should function under Linux. I mention this because I like how some of the ones for the Mac work.

The reader for Linux is so-so. Since there is only one (and I talked about E-book readers at length a few months ago) I’ll just say it is available in the Debian/Ubuntu/Mint repositories and as a separate download. Considering the alternatives are simply PDF readers it is a big improvement. So essentially we in the Linux world are stuck with only a few formats we can access. Wouldn’t cha know it most of the odd-ball ones are not accessible on either the Mac or Linux platforms. This isn’t to mention my MP3 player which will only do .txt format documents.

Given the problems with the various formats I was looking around for a converter. I actually found one which works pretty well. It’s called Calibre. I don’t know if it is available for the Mac, but if someone is running a virtual machine with Linux or is able to install it with a package like MacPorts then that’s a non-issue. This program will convert to and from any of what looks like close to two dozen different formats. This means effectively if someone purchased a physical E-book reader which has it’s proprietary format in the list they now have access to a wider range of content. Naturally most of the content I have seen has been scanned and run through an OCR and not proof-read. This means some of the words are garbled in the original form. Since it’s a case of garbage in and garbage out I don’t expect miracles. None the less it should be interesting to see how some of these E-books look on my MP3 player.

By BlankMike • Uncategorized • 1

Dec 29 2011

FireFox tip

Those of us in Canada are aware how our government keeps “shooting itself in the foot”. Those outside the country may not be aware just how silly and petty our government can get. For example they have this thing about promoting Canadian culture in the media. Not too bad on the surface of things right? Rather than encourage Canadians to produce our own material they de-regulate the media so they can purchase more American programming. Some of the stuff from South of the border is OK so it can rise and fall with the local ratings. However they take it a step further. If a Canadian station schedules a TV show at the same time as it is scheduled on an American station the cable companies are supposed to replace the American station with the Canadian station. This way the Canadian station can count local commercials as “Canadian content”. Of course this adds five minutes to the amount of commercials… The nasty part comes when we get to on-line content.

When viewing on-line content the government censors what we can see. I’m not talking about stuff like kiddie porn. I’m talking about over the air content. If a show is broadcast in Canada on a Canadian station, but is supplied by an American outfit Canadians have to go through the Canadian web site to view it. Part of the problem is some sites view on-line content as a preview rather than an archive or time-shift. So often not all of a show is available. Some times it is even missing. Yet on the American site it is all there. In this situation we have a message stating “This content is not available in your area”. Very frustrating…

There is a plugin for FireFox which seems to work with a few sites. It is called “Modify Headers”. True to the name it changes the header of what is sent out by FireFox to indicate a different geographic area. Essentially it persuades the computer to lie for you. This is different than going through a proxy server. The proxy server may actually be located in the same geographic area so essentially your computer wouldn’t by lying.

The directions for using this plugin are not inherently obvious. After some reading on the net I found out what to do.

  1. Surf to the site which has the blocked video.
  2. Under the tools menu access the Modify Headers plugin.
  3. In the first box enter “X-Forwarded-For” (it should auto-complete).
  4. Enter a numeric IP for the area in question (12.13.14.15 is suggested for the States,  no suggestion for Europe is given).
  5. Refresh the page.

At that point things should run properly. Apparently this doesn’t work on all sites. The reason I waited to post this was to see if I could find a site through every day surfing which wouldn’t work. So far I haven’t found one.

Followup: I tried this on a Mac running Snow Leopard. It didn’t work. Worst case… It should work in an emulator.

By BlankMike • Browsers, Cross Platform, Documentation, Review, Software, web browsers • 0 • Tags:

Dec 6 2011

Linux Mint 12

This article is presented for those with Intel Macs (and PCs) who choose to have an alternative operating system available. It is possible to install it as a Dual-Boot system, Virtual Machine, or just run it from the live DVD.

Late last month (November) Mint 12 was released to the public (free). Mint is a full multi-media distribution of Linux. There has been a lot of extremely positive press about this version. It’s almost as if someone hired the PR departments from both M$ and Apple. ;-) With all due respect, I disagree with their evaluation. I work with older computers and find it is barely usable. Here is why:

  • On a 32bit IBM Netvista running at 2.5GHz with 1GB of RAM it takes multiple attempts to install from the CD.
  • Once installed the default setting is to run Gnome 3.
  • The Gnome 3 desktop is very bare. There is no menu only the icons to access programs directly.
  • In order to access any sort of menu from Gnome 3 the user has to right click on the desktop and open a shell. From there they have to type “gnome-panel” every time they login.
  • The different system settings are spread across three different menu items.
  • In Gnome 3 I have yet to find a way to add items to the panels.
  • Most users have apparently stayed with Gnome 2 because most of the features they want are still there.
  • To change the panels in Gnome 2 the process has been changed from a right click to holding the <Alt> key while right clicking.
  • The whole system is slower than previous releases.
  • This release looks like it is becoming more bloated (still not as bad as as Windows or OS X).
  • The operating system is convinced my desktops are laptops. This means a whole lot of useless software gets installed.

There are a number of good reasons to consider this version:

  • IF it installs correctly, it is stable.
  • The eye-candy is appealing.
  • Under Gnome 2 all the previous software remains available.
  • Although I haven’t tried it, I have been told KDE works really well.
  • It includes newer programs than previous releases.
  • It installs very well in a Virtual Machine.
  • It is still faster than Windows and OS X.
  • The authors have bent over backwards to support laptops and netbooks. This is somewhat useless if it is installed on a desktop though.

My final impressions are the authors are telling the users what they want as opposed to listening to what the users want. Also that the new desktops resemble pre-OS X Macs or Windows 3.1 without the speed.

By BlankMike • Cross Platform, Emulation, Macintosh, Microsoft, OS X, Software, Updates • 0 • Tags: , ,

Nov 29 2011

Ghostery

Ghostery is an add-on to FireFox (and other web browsers) which stop sites from tracking users as they surf the web. Installing it depends on which web browser and which version is being used. A good place to start is either tools, extensions, or add-ons. Once installed and the browser is restarted, Ghostery will go through three or four configuration screens. The last screen lets the user select which tracking cookies/bugs to block.

One of the options is to let the user know which cookies/bugs are being blocked. My record is seven or eight sites. The average is around three. If you are like I am and want to maintain at least a minimum of privacy on the net, this is a good place to start.

By BlankMike • Ads, Cross Platform, Freeware, General, Software, Software Ads, web browsers • 0 • Tags: , , ,

Nov 2 2011

VNC Quick start

Frequent readers of this web page will realise I like to learn how to do things (this is the reason for the long gaps between my posts). I hope readers find this information to be useful… After seeing a member of another club demo it on a smart phone for me, I decided to give it a try myself. Be aware this is only scratching the surface of the topic and it can be a security risk if not implemented safely.

VNC is a way to control one computer with another. It sends screen shots over a network. It also accepts commands sent to it. The end result is a window which duplicates the desktop of the machine being controlled. The only thing is the machine being controlled needs to be on or at least in stand-by mode.

I decided to go with what I could find for free. A big surprise there. ;-) Since Bill insists on a link to the Mac or Apple // world I figured I would start with that. Because of this insistence it turns out I found the simplest way to implement the use of VNC. Thanks Bill. It saved me a lot of headaches.

The first thing to realise is there are two parts to the process. The first is the server side on the host machine and the second is the client on the guest machine. To simplify the mind set, think of the server being placed on the machine to be controlled and the client installed on the controller machine. Only one server is needed but several clients can be run at the same time.

Setting up the server on the Mac is incredibly simple. Incidentally it has been a free part of OS X since 10.4. Since each version of the operating system implements it differently I’ll describe things in general terms. A functional router is needed. The IP addresses can be assigned by DHCP or the machine can have a static IP. This matters more on the server side than it does on the client side. This is because the client needs to know what address it needs to connect with. This can be found by going into the network preference of the server and searching for it.  Once the host address is known, go into the sharing preference on the server and turn on screen sharing. Going into the advanced setting here is a good idea too. In my case I set things up so only administrative users can connect with a password which is different from the login password. This is where it can get dangerous. We all know how fast passwords can be cracked. Leaving a host machine on all day is generally not a good idea.

Clients are a little more complex. In this case I picked a Linux client and gave it a try. It took about five minutes figuring out what to do before it worked. The client generally needs three things… The IP address of the server, the login ID, and the password set up in the sharing preferences. Once I managed to get all that worked out things went fairly well. Of course I was connecting on my own LAN instead of coming in from the outside. But that’s another story.

There are a couple of things to watch out for. Not all clients which call themselves VNC clients will work properly. At last nights meeting a member tried to connect with a Windows box only to find the client expected to find a commercial server written by the same company. A lot of the “free” clients on the Mac or Windows platforms are crippled by time or performance issues. Not all software will run properly over VNC. I’ve had issues with DOSBox. The screen froze. The user interface is also slower. When reading an e-book I found a single mouse click on the client occasionally translates to multiple clicks on the server box. Video over the LAN is also slower. They will be jerky on the client side but play normally on the server side. Any sound generated as a result of VNC will be on the server side not the client side. If there are multiple clients connecting to the same server, should one of them decides to logout of the account then everyone is logged out. This is different from disconnecting from the server. If someone disconnects from the server, they can reconnect at a later time.

If implemented in a safe way I can see a lot of advantages. For example a person sitting at one machine can do multiple things on multiple computers at the same time. A friend says he uses a similar program to manage his bittorrent downloads without having to sit in front of the machine in his basement. If a persons workplace has implemented a ban on certain web pages, they can use VNC to have their home computer access them. If the computer can control some devices in the home the homeowner can give the impression they are at home even though they are in a remote location. The reason Microsoft and presumably Apple installed the software was to allow remote access for their “technicians” to fix problems with minimal customer input. If the user has a webcam installed on the server machine they can run the software from a different location. Since the monitor doesn’t have to be on for this to work, all this can be done secretly. While having a computer (or tablet) searched at the border, the agents will find only the software the user has on the machine they have with them. If the files the agents are looking for are on a different machine (which is not visible) they have no reason to seize the users traveling machine.

My personal opinion is this is cool, but insecure, and is minimally useful.

By BlankMike • Uncategorized • 0

Oct 13 2011

rsync

This is a command coming from the *NIX world I found to be useful for maintaining a backup for important software. It works either on a single computer or with two computers. The details can be found in the man page for the command. I’d like to thank Mike Doob from the MUUG for reminding me about this command.

The simplest way to use the command is “rsync <file list or directory 1> <file list or directory 2>”. All it does is copy files from area 1 to area 2 if they are newer than those in area 2.

To copy files from one computer to another the account name and computer name are needed. An example would be “rsync sbalmer@microsoft.com:/Secret_Meetings_To_Control_The_World.txt timc@apple.com:/Sunday_Coffee_With_Friends.text”. Incidentally, since they are different computers, passwords are needed.

I tried this a number of years ago with 10.2 and FreeNAS (FreeBSD) and apparently that was the only configuration which (according to everything I read on the net) would not work.

By BlankMike • Cross Platform, Macintosh, OS X, OS X Shell • 0 • Tags:

Oct 13 2011

Current updates to 10.6 (32bit)

Last night I noticed there were some updates for Snow Leopard. I decided to install them. When I sat down at the computer an hour ago I saw there were errors and nothing was installed. This seemed oddly familiar when (back in the day) M$ was trying to get its users to leave ME and go with XP. They would push out failed updates and updates which would crash the system unless the user did a clean install…

Assuming this was a failed update I decided to install the updates individually. First was the security update. Next was Safari. Finally was iTunes. Doing it this way, everything installed without complaints.

I can’t be sure of the cause of the failed updates. Since my LAN is working properly I know the problem lies beyond my firewall…

By BlankMike • Uncategorized • 0

1 2 3 4 5