XPost: sci.electronics.design, sci.electronics.misc   
   From: adrian@qq.vv.net   
      
   On 7/3/2013 1:44 PM, Spehro Pefhany wrote:   
   > On Thu, 07 Mar 2013 12:49:27 +1000, the renowned Adrian Jansen   
   >  wrote:   
   >   
   >> You are right, but seems like someone has solved the RF problems once   
   >> for each of the useful bands, then its a piece of cake to interface with   
   >> sensors and one end and display/alarm at the other.   
   >>   
   >> For an example, the tyre pressure monitor systems at 433 MHz.  10 gram   
   >> package, including battery, you screw on a tyre valve.  Monitors tyre   
   >> pressure and temperature for about 1-2 years of operation.  Reports real   
   >> time, every minute or so, to in-car readout.   
   >   
   > Frequently fails mechanically, causing loss of tire pressure, allows   
   > tire shops to charge for a "rebuild kit" whenever they swap a tire,   
   > requires a trip to the dealer (or specialized equipment/knowledge) to   
   > replace, even with an OEM replacement part.. other than that, they're   
   > just spiffy.   
   >   
   >   
   > Best regards,   
   > Spehro Pefhany   
   >   
      
   Really I was commenting on the RF stuff.  Certainly that seems to work   
   as well as needed.  Whether the rest of the design is as good as the RF   
   section is a different kettle of fish.   
      
   The aftermarket units using sensors like Tyredog seem to have a learning   
   mode to accomodate sensor changes without special tools.   
      
   Personally I would be happy if the system just warned that a tyre is   
   going down, before it wrecks the tyre.  Identifying which tyre is at   
   fault is a secondary, and usually very easy, job.   
      
   --   
   Regards,   
      
   Adrian Jansen           adrianjansen at internode dot on dot net   
   Note reply address is invalid, convert address above to machine form.   
      
   --- SoupGate-Win32 v1.05   
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