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???
07/06/11 19:09
Modified:
  07/06/11 19:10
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 		 #182814 - one interesting thing I learned
Responding to: ???'s previous message
8x8 electromechanical display - often used on busses or similar
I haven't seen one of them in years! They've all been replaced by LED or other electronic displays
they are still preferred in some locations where it is considered important to have signage when the engine is off.

one interesting thing I learned working with these (while designing LED signs I still had to support older signs) is that most (all?) transistors can withstand the same reverse Vce as they can forward. i have seen no datasheet with a max Vce(reverse) stated

Erik


List of 49 messages in thread
TopicAuthorDate
problem rgarding uln and udn            01/01/70 00:00      
   They are different in every sense!            01/01/70 00:00      
      problem rgarding uln and udn            01/01/70 00:00      
         You forgot your links            01/01/70 00:00      
         Basic electronics            01/01/70 00:00      
            Clarification - more Basic Electronics            01/01/70 00:00      
            probelems regarding udn 2892            01/01/70 00:00      
               Still Basic electronics            01/01/70 00:00      
                  Links            01/01/70 00:00      
                     That'll be why he's still struggling after all these weeks!            01/01/70 00:00      
               open emitter            01/01/70 00:00      
                  Open collector            01/01/70 00:00      
         RE: i am not getting you            01/01/70 00:00      
   Did you really read datasheets?            01/01/70 00:00      
      problem rgarding uln and udn            01/01/70 00:00      
         relay matrix???            01/01/70 00:00      
         This doesn't make sense!            01/01/70 00:00      
            8x8 relay matrix?            01/01/70 00:00      
               relay matrix?            01/01/70 00:00      
                  not quite            01/01/70 00:00      
                  one interesting thing I learned            01/01/70 00:00      
               Unless...            01/01/70 00:00      
                  problem rgarding uln and udn            01/01/70 00:00      
                     lightning fast relays            01/01/70 00:00      
                        problems regarding uln and udn            01/01/70 00:00      
                           both            01/01/70 00:00      
                           None of this makes sense!            01/01/70 00:00      
                           It appears you need latching relays            01/01/70 00:00      
                              Latching relay is still slow            01/01/70 00:00      
                                 You're right, but the relay spec's should reveal that            01/01/70 00:00      
                              well, if he does ...            01/01/70 00:00      
                                 use toggle types ... they were around once ...            01/01/70 00:00      
                                    SPI + latched shift registers are good choices            01/01/70 00:00      
                                       The protocol is good ... but not necesary here            01/01/70 00:00      
                                          SPI is excellent for driving long shift registers            01/01/70 00:00      
                                             tell us, Per, what data types does SPI support?            01/01/70 00:00      
                                                Making Mountain Out Of Mole Hill            01/01/70 00:00      
                                                   protocol and/or command structure            01/01/70 00:00      
                                                No, SPI does *not* have both commands and data!            01/01/70 00:00      
                                                   Where you sit determines what you see            01/01/70 00:00      
                                                      Totally missing the point            01/01/70 00:00      
                                                         The major advantage            01/01/70 00:00      
                                                      Where Richard Sits......            01/01/70 00:00      
                                                         From where I sit...            01/01/70 00:00      
                                                      Always important to follow up the progress of technology            01/01/70 00:00      
                     Language barrier?            01/01/70 00:00      
                        Further question            01/01/70 00:00      
                     Sorry, double posting...            01/01/70 00:00      
   Cross-Post?            01/01/70 00:00      

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