Sunday 19 June 2011

A very handy tool

Today I tested a tool I bought recently on the recommendation of a friend. Do you know these ratchet lashings used for securing cargo on a lorry or trailer? They are flat sturdy belts with a hook on one side, and then a separate ratchet mechnism with a hook. Have you ever thought you could use that to pull or lift some heavy stuff just a little bit?

Well, it does not work, because the belt is wound up on a small roller, and since this is only meant to tighten just that last bit to secure a load, the roller can only hold very few turns of belt.

Now, here comes the Swedes, who invented just the tool that can do both:
It comes with a 10-m long belt, and then a ratchet mechanism that's slightly more complicated than the usual setup. It has two alternative ways of feeding the belt through it, thus turning it into a cargo lashing system, or a small hand winch. The best part: it packs into a very small space due to soft belt instead of stiff steel wire, and it is very lightweight. In fact a lot of people here carry it under the seats of the snow mobiles as recovery equipment.

Today I had to pull a euro palette loaded with over 200 kg of stuff about a metre on the wet flat bed of a trailer into a better position. Easy as pie with this thing.

Here are the instructions, which are in Swedish, but the pictures basically tell everything that's important.
Another very nice feature of this winch is that the loose end can just be pulled straight through the mechanism. The locking system auto-releases and thus makes it possible to pretighten very quickly before using the handle for doing the tough stuff.
Is there any minus to it? — For heavier loads (I don't know yet how heavy, this is rated up to 400 kg), the lever of the handle is a bit short and it might get too hard to operate. But that just serves as an over-load protection.

Click on the images for larger version.

You want this? — You can get it in well-stocked tool shops across Finland and Sweden, and I guess elsewhere in the Nordic Countries, too.

Sunday 1 May 2011

Building a silent computer

This is a tricky one. There are so many zillions of PC-type computers out there, and so many components to build a computer for a purpose, that it is very hard to find an ideal combination of parts. This is not exactly becoming easier, if you live in a location far from any big city. Thus after a lot of searching around in the internet, I simply went to a large computer shop to ask the staff some question. In my case I was lucky and immediately found a very knowledgable sales person, who understood exactly what I wanted, and came up with a custom selection of parts to build a computer, which is quiet enough to sit in the living room near the TV, and which is powerful enough to run three DVB receivers.

In my case one of the requirements was that the mainboard and the case can accommodate three PCI cards. Nowadays, lots of boards do not anymore have that many PCI slots. I have earlier had very bad experience with so-called "riser cards." Riser cards plug into one PCI slot and allow to connect two or three PCI cards to the same port, often at a 90° angle. However, many of these cards are faulty, and if you have very demanding PCI cards, there won't be enough power to both cards through the riser card. Therefore stay away from those. Besides finding the right mainboard, this also meant to find a suitable ATX case, which has enough space to accommodate three cards standing upright straight on the mainboard. The choice of keyboard and mouse was determined by my wanting something that looks nice on the coffee table and that it had to be wireless of course.

Here's the parts list of my solution, but your solution might look very different, since there are so many choices available.

  • CPU: AMD Athlon II X4 640, 3 GHz
  • Mainboard: Asus M4A88TD-V EVO/U w/ on-board graphics with HDMI output
  • Power supply: Corsair TX750W
  • CPU cooler: Scythe Ninja 3
  • RAM: Kingston Valueram 4GB
  • Case: Antec 300 ATX case
  • Harddisk: 2 x Samsung Spinpoint F3, 1 TB
  • DVD/BluRay/CD: Lite-On IHES208-31 DVD+/-RW and Blu-Ray player
  • Mouse: Apple Magic Mouse
  • Keyboard: Apple Wireless Keyboard
  • Bluetooth: cellular line BT Micro Adapter (USB dongle)

In my case, I am using the following two receiver cards, which are widely reported to work well together:

  • Hauppauge WinTV NOVA HD S2 PCI, single DVB-S/S2 tuner for HDTV
  • Hauppauge WinTV NOVA T-500 PCI, dual DVB-T tuner


This hardware turned out to be noisier than I hoped for. On closer inspection it turned out that the Antec 300 case came with two fans, which are not controllable by the mainboard. Instead, they simply have switches dangling about on cables, which allow three fixed settings: low, medium, high. Thus these two will be replaced as soon as possible for temperature controlled fans.

Secondly, I found that the large doors of the case (both panels can be easily opened without tools to give full access to the internals), are resonating and thus making the noise worse. Thus I went to the local car part shop and bought 10mm think adhesive soundproofing for cars, cut it to shape, and stuck it into the box. The result is a much quieter computer, high frequencies and hollow metallic noise are practically gone, and only less disturbant low frequencies are audible. Together with the change of fans, this will be a very quiet machine in the end.

Power supply: the 750W power supply seems a bit over-the-top for a machine like this. The argument here was twofold. A big power supply will not become hot when only small power is drawn, thus its fan won't spin up very high except in rare occasions, which will make for a quieter computer. Secondly, too many computers suffer from too small, i.e. cheap, power supplies, which aren't really up to the job of keeping all the internal components happy. This is expressed, e.g., in memory failures. With this big power supply, I hope I won't encounter any of that.

Saturday 30 April 2011

A computer to watch TV?

We have an unusual TV setup, we want to receive free-to-air satellite programmes from back home, but we also want to watch the local free-to-air terrestrial TV programmes. Thus we need a combined DVB-T and DVB-S/S2 receiver, that of course should be able to record on harddisk. Such a device is hard to come by in form of a set-top box. In fact thus far I have come across only one, which seems to be based on some Linux derivative and which is modular in that allows for plugging in receiver modules of any kind. However, the price was very high.

The next-best solution is to build a "set-top box" yourself using Linux and a software package called MythTV, which is a free package to watch TV. This package allows you to configure as many different TV cards as you want, limited only, it seems, by the processing power of the computer. MythTV even has a web interface, which allows you to schedule recordings while away from home, and to watch programmes recorded previously. Moreover, the computer can of course be used as a media server for the family, and store the backups of other computers etc.

Here I decided to use the Ubuntu variant of Linux. Over the next several posts, I will document the installation in detail, so that anyone can repeat the process (I hope). Please feel free to comment on the setup, esp. hints on how to do it better are naturally very welcome.