Hey guys. Let me start off by saying I’m a 17 year old young man and I’m incredibly interested in electronics. I have a fair understanding in the field in terms of comprehending and then constructing a circuit diagram. I learned what I know by taking my dad’s old university books and actually reading! But unfortunately most of the books are badly damaged and some completely destroyed. But none the less, I can also piece together several circuits or modify an existing one but I have absolutely no idea where to start or how to go about designing my own circuit. And that’s how I turned to the internet for help.
I want to build a digital tachometer for a Honda CBR400RR. It should consist of 5 seven segment numerical displays on which the RPM should be indicated and more or less 50 LED’S as a bar graph with another LED indicating “It’s time to shift”.
This is how the story went... I found a bar graph tachometer circuit using LM3914’s that i would have initially used. All I needed now was to add a circuit that will indicate the RPM on 5 seven segment displays. This is where I got confused... If you look at the original tachometer of the Honda CBR400RR (which is analog), it goes from 0 to 16 and on the right it indicates “x1000”, which, if we take 16 for example, will be 16 000 (16x1000). But when I searched for a circuit to display the RPM on seven segment displays, all I could find was circuits consisting of only 4 seven segment displays, which would not have worked. Since the bike is capable of producing a RPM of 5 digits, 4 digits implies that the value displayed be multiplied by ten. Since I want the indications simple but still very accurate, only 5 digits will be completely sufficient to my liking, but unfortunatley I lack the knowledge to adjust the curcuit to consist of 5 numerical displays. But then I had an Eureka moment! Since there is very little space (if any) on a bike for extra stuff, my circuit would have to be really small (And it would be placed in potting compound to prevent the vibrations of the bike from loosening the soldered equipment, which makes it even bigger). But these circuits are generally large in size due to the amount of components used. The first answer that came to mind was “Code”. Microcontrollers is the solution to really restrict the size of the circuit! But unfortunately my knowledge is even more restricted in terms of microcontrollers... And this is where you fine gentlemen and ladies would be of great help...
I need someone to be so kind to please design me a circuit diagram. You can use whatever components you wish (preferably microcontrollers) as long as the final schematic would be small in size if built (bare in mind I can’t work with SMT components since I don’t have a 10ft magnifying glass and neither do I have a solder station with a super fine tip). I will be using 0.28” seven segment displays (common anode or cathode, basically designers choice), 50x5mm LED’s and the “shift” LED will be 5mm as well. The signal will be retrieved inductively by wrapping the signal wire around the spark plug cable.
I hope someone can help me. Thanks guys! I think that’s all info you need!
I want to build a digital tachometer for a Honda CBR400RR. It should consist of 5 seven segment numerical displays on which the RPM should be indicated and more or less 50 LED’S as a bar graph with another LED indicating “It’s time to shift”.
This is how the story went... I found a bar graph tachometer circuit using LM3914’s that i would have initially used. All I needed now was to add a circuit that will indicate the RPM on 5 seven segment displays. This is where I got confused... If you look at the original tachometer of the Honda CBR400RR (which is analog), it goes from 0 to 16 and on the right it indicates “x1000”, which, if we take 16 for example, will be 16 000 (16x1000). But when I searched for a circuit to display the RPM on seven segment displays, all I could find was circuits consisting of only 4 seven segment displays, which would not have worked. Since the bike is capable of producing a RPM of 5 digits, 4 digits implies that the value displayed be multiplied by ten. Since I want the indications simple but still very accurate, only 5 digits will be completely sufficient to my liking, but unfortunatley I lack the knowledge to adjust the curcuit to consist of 5 numerical displays. But then I had an Eureka moment! Since there is very little space (if any) on a bike for extra stuff, my circuit would have to be really small (And it would be placed in potting compound to prevent the vibrations of the bike from loosening the soldered equipment, which makes it even bigger). But these circuits are generally large in size due to the amount of components used. The first answer that came to mind was “Code”. Microcontrollers is the solution to really restrict the size of the circuit! But unfortunately my knowledge is even more restricted in terms of microcontrollers... And this is where you fine gentlemen and ladies would be of great help...
I need someone to be so kind to please design me a circuit diagram. You can use whatever components you wish (preferably microcontrollers) as long as the final schematic would be small in size if built (bare in mind I can’t work with SMT components since I don’t have a 10ft magnifying glass and neither do I have a solder station with a super fine tip). I will be using 0.28” seven segment displays (common anode or cathode, basically designers choice), 50x5mm LED’s and the “shift” LED will be 5mm as well. The signal will be retrieved inductively by wrapping the signal wire around the spark plug cable.
I hope someone can help me. Thanks guys! I think that’s all info you need!
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