Since people keep coming to my blog looking for hints on how to deal with wrong radio controlled clocks and find only my annoyed post about a particular specimen with its stupid programming that lets is be wrong on the days of daylight savings time changes, I thought I’d put together a few hints for other kinds of radio clock problems:

• Don’t position it too far inside the building, closer to windows may be helpful (preferrably towards the transmitter, wherever that is for your area). This especially applies to buildings with reinforced concrete walls.
• Not too close to other electronic devices, especially those transmitting radio signals themselves. Also, the proximity to metal objects can cause interferences.
• Cheap receivers may have problems with weak batteries, so try fresh ones.
• And you shouldn’t forget to look at the often available symbol indicating whether the clock still receives a signal at all. For if it has to keep running off its own quartz, a cheap model might show visible differences after only a few days.

Further notes:

• Since the signal data usually offers only very little means of error detection (single parity bits for parts of the data; even 2 (or 4 or 6…) bits received wron cannot be detected), low reception can easily cause the clock to set the wrong time, especially if it’s programmed (too) simply and does not compare the signals over several minutes to avoid such consistencies. (The time signal is transmitted every minute, containing 59 bits with 1 bit per second.)
• Most clocks don’t check the signal all the time, but at most every hour or a few times per day – or just once, and hopefully not at 0:00 like the specimen I mentioned.

Hope this helps someone… If you got anything to add, note, or correct, feel free to do so in the comments.

Photo by Martin Schmid – Fotolia.com