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The MSF signal is a bit of a mess

28/07/2010 – 00:06

I am working on another clock, this time with MSF (Rugby/The time from NPL) radio time setting. I know, I need to document the last one… Anyway, I finished the decoder today.

The MSF signal is frankly a mess. Things seem to have been added and then removed over the years. There are four different length pulses and various additions. Compared to the nice clean DCF77 signal it’s horrible, but unfortunately I can’t get DCF77 to work reliably here. In fact I bought a DCF77 clock but it has never been able to receive a good enough signal to set itself.

As others have discovered the MSF signal is much cleaner at night, but filtering out the noise during the day isn’t too hard. I wrote the decoder in assembler and it basically waits for a valid bit and then locks on to that, ignoring everything until 950ms have passed from it’s start. It also filters out too short and too long pulses and does some debouncing.

By mojo | Posted in avr, electronics, microcontrollers | Comments (0)

Blister packs

03/07/2010 – 17:07

Why does medication for arthritis come in packaging that is hard for people with arthritis to open?

By mojo | Posted in Uncategorized | Comments (0)

Mitsubishi Colt squealing brakes

28/06/2010 – 21:46

A few months ago the brakes on my Mitsubishi Colt started to squeal as I was coming to a stop. It was less than a year old and due for a service in another couple of months so I decided to just wait.

At first Sparshatts said on the phone they would sort it out as part of the service (which was covered by the combined service and breakdown cover policy I had with the car), but when I got there they were unwilling to commit to anything. In the end they apparently blew some air on them to clean off any dust, but after a few miles they started squealing again.

I’m not very impressed. A one year old car should not have brake problems, even if the performance of said brakes does not seem to be affected. I suppose I will have to look into solutions myself.

Otherwise the car is still excellent in most other ways. There is a nasty corner near where I work that is obscured by that pillar I mentioned in my review but I have learnt to look from a different angle there now. I adjusted the mirrors to give a better view of the blind spots which seems to have worked really well, and they are designed such that only the actual mirror moves rather than the whole body so they don’t get pushed out of place by the car wash.

By mojo | Posted in Uncategorized | Comments (0)

PayPal – no protection after 45 days!

25/06/2010 – 19:31

In the EU everything electrical comes with a two year warranty. I bought an MSF receiver module on eBay. It arrived from overseas and it took me a couple of weeks to get around to testing it when I realised it did not work.

I opened a PayPal dispute and they closed it because it had been longer than 45 days since I bought it. Some stuff takes nearly that long just to arrive from China! As usual PayPal are cocks.

I left the seller negative feedback because he refused to accept a return. I asked Santander about a charge-back but they refused too, the asshats.

By mojo | Posted in Internet, law | Comments (0)

Same old Tory party, what happened to the LibDems?

21/06/2010 – 13:43

Selling off rail track built with £5bn of public money for a mere £1.5bn. Remove waiting time limits from the NHS, thus driving people to go private.

Same old, same old. This coalition is a joke.

By mojo | Posted in politics | Comments (0)

Mouse+Joystick “computer” mode for the Retro Adapter

18/06/2010 – 18:18

I have just finished updating mouse support on the Retro Adapter so that it now supports a mouse and joystick simultaneously. I am still trying to think of a good name for it but for the moment I am calling it “Computer Mode” because it is ideal for emulating machines like the Amiga or Atari ST which use both a mouse and joystick. No need to unplug or re-configure anything, it just works.

Hopefully the next batch of RAs will arrive soon and I can get on with selling them.

By mojo | Posted in electronics, hardware, microcontrollers, Retro Adapter | Comments (0)

Dating Recordings by Power Line Fluctuations

18/06/2010 – 18:14

An interesting article.

Summary: Using power fluctuations in the national grid police claim to be able to date a recording precisely. The fluctuations affect any mains connected equipment, and allegedly even battery powered devices.

The police seem to love this kind of highly dubious forensic evidence. Let’s look at their record.

Fingerprints – not unique and never a perfect match like on TV, in fact matching is very much an art. Unreliable.

DNA – started out as a 1 in 1,000,000,000 chance of a sample matching two people, now it turns out that even with a good sample it’s more like 1 in 1,000,000 (i.e. 60 other people in the UK match).

DNA amplification – taking a small sample of DNA and build it up. The Omagh bombing trial collapsed after it was revealed to be bunk.

Firearms residue – a single spec was enough to convict Barry George until it was revealed that it was worthless as evidence. An innocent man spends years in jail.

CCTV – video evidence is powerful and solves crimes, except that most of the time it doesn’t.

Lie detectors – need I even go into them?

By mojo | Posted in law | Comments (0)

Making the Umax PowerLook 2100XL scanner work on Windows 7

15/06/2010 – 14:56

I had an interesting challenge at work a few weeks ago. A customer wanted a new PC running Windows 7 but he needed to keep using his rather old A3 scanner, a Umax PowerLook 2100XL. Umax only provide Windows XP drivers and installing them on Windows 7 stops the system starting up.

Something about the combined installer for the software and drivers was preventing it from working.

The solution was to install the software on a Windows XP machine and then copy the files manually from the XP system to the Windows 7 one. I then pointed Windows 7 to the copied files when it requested drivers for the scanner. The application program was copied in the same way and I simply set up a shortcut on the start menu pointing to the program file.

Aside from the main program directory the drivers were spread out in various system directories. It took a while to find them all.

It took me a long time to sort all that out. There are a lot of posts on the internet written by people with the same or similar scanners who are unable to make them work on Vista or Windows 7. As far as I know we are the only people who have ever managed to make it work with Windows 7.

By mojo | Posted in hardware, software, windows | Comments (26)

Maplin Soldering Fume Extractor mini review

12/06/2010 – 23:38

I decided it was time to stop breathing in leaded solder fumes and get a fume extractor. Being on a limited budget getting a new iron with one built in or a larger unit was out of the question. Actually we have an iron with extractor on it at work (Blackjack hot-air rework station with very handy electric de-soldering tool) and it works brilliantly. Maybe one day.

Maplin were for once actually the cheapest source of desk-top extractors so I decided to take a chance on their £15 model. Turns out it was quite a good choice as it seems to work pretty well. It produces about 55dB at 30cm which is about where it needs to be on the desk to work well. The noise is just about acceptable, not quite enough to be annoying or distracting and it fades into the background pretty quickly. It’s about the same as a noisy PC fan.

It takes up a fair bit of room compared to an iron-mounted or vice-mounted version but you can angle it up and down which helps when using PCB holders and the like. It seems to such most of the fumes away from your face. Some still get through but I find I don’t the the usual symptoms like headaches, watering eyes, dry throat etc.

It comes with three filters. No idea how long they will last, obviously it depends entirely on how much you use the fan. They are easy to remove and clean, and fairly cheap to replace.

By mojo | Posted in electronics | Comments (2)

… and so it begins

08/06/2010 – 22:52

Massive public service cuts and farming jobs out to private companies. Tell me again Mr Cameron, Mr Osborne, how is this different to the 1980s?

Actaully, to be fair, it is different. It’s worse.

Cuts are inevitable, but doing so much so soon will cause a double dip recession. Getting rid of government jobs and replacing them with private ones costs more, puts people out of work and on to benefits, and you end up with poorer services.

There is a responsible way to do this and then there is the Tory way. As usual they look out for the rich, make money for private companies with lucrative government contracts and screw everyone else.

Dave was right, this is going to hurt.