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???
12/26/08 20:21
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 		 #161139 - Too soon to start worrying about voltage
Responding to: ???'s previous message
As I mentioned I'm trying to just understand how to make it "go." If I can do that, then I can worry about logistics concerning whether I've got enough voltage/too much etc. My plan is this: If I can figure out how to turn on and off all segments individually, I'll create a lookup table and flash the segments needed sequentially (hopefully fast enough) to make it look like the entire display is "on". I'm hoping that will allow me to use just 4.5v to run the whole thing.

I'm going to read your first paragraph and see if I can understand a way to do it. As of now, I'm still not seeing it.

List of 40 messages in thread
TopicAuthorDate
Help with 4 digit LED 7 segment display            01/01/70 00:00      
   common cathode            01/01/70 00:00      
   Maybe it is a standard display            01/01/70 00:00      
      It's standard, but I can't find a spec sheet            01/01/70 00:00      
         an old-time part, perhaps?            01/01/70 00:00      
            The 8650 is a standard alarm clock IC            01/01/70 00:00      
               add up the forward voltages, adjust the resistors ...            01/01/70 00:00      
                  Diagram            01/01/70 00:00      
                     It's all up to you ...            01/01/70 00:00      
                        Too soon to start worrying about voltage            01/01/70 00:00      
                           Be careful ... you only have one of these ... right?            01/01/70 00:00      
                     beware            01/01/70 00:00      
                        Interesting concept            01/01/70 00:00      
                        Don't think so            01/01/70 00:00      
                           make a FULL schematic            01/01/70 00:00      
                              Of course            01/01/70 00:00      
                           Careful, now!            01/01/70 00:00      
                     Diagram mis-labeled, sorry            01/01/70 00:00      
   Please consider that....            01/01/70 00:00      
      Lookup table            01/01/70 00:00      
         'Ohm" it out            01/01/70 00:00      
            I don't see how            01/01/70 00:00      
               then forget transistors            01/01/70 00:00      
         2-Anode 12-Cathode Drive Diagram            01/01/70 00:00      
            Thanks            01/01/70 00:00      
   It works like this....            01/01/70 00:00      
      Vbe, not Vce            01/01/70 00:00      
         that was probably I who did that ... and you're right            01/01/70 00:00      
            Well...            01/01/70 00:00      
               take a close look            01/01/70 00:00      
               I doubt it            01/01/70 00:00      
                  Possibly a radio section too            01/01/70 00:00      
                  Crystals            01/01/70 00:00      
                     That C### is a capacitor number, I think            01/01/70 00:00      
      How about this?            01/01/70 00:00      
         use PNP at the high side            01/01/70 00:00      
         ...And get rid of the extra resistor in the...            01/01/70 00:00      
            Thanks. Time to test and draw            01/01/70 00:00      
               multimeter solution            01/01/70 00:00      
                  Similar to what I did            01/01/70 00:00      

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