Dual 7 segment display

[zerodegreec]

Resources on how to replicate a small 4 digit display to a Large digit display. Problem I foresee is that the small display and large display will use different voltages, and the existing chip wont handle the load. Do I build an array of transistors to switch each segment of the large display?


I would like a gentle nudge in the right direction. I am building a Radar speed display for my street. I have a radar gun that fits the bill, but would like to extend its readout to a nice big display so drivers can slow the hell down.

Use a display with this 6.5" display

 

[Usama Siddiqui]

the best thing is transistor switching,but if your chip is having issues with that too then simply use optocouplers it will isolate the chip with the power circuit. but handle the optocoupler with care coz it gets burnt quickly at any high current

 

[chuckey]

The radar gun in the picture uses a LCD display, these take NO current, so you need to use some sort of FET transistor driver for your extension display.
Frank

 

[hexreader]

I suspect that your plan will back-fire.

Kids will come from miles around to try and set new speed records.

Might be worth checking with your local police that this really is a good idea.

Speed display signs near me only show speeds below the legal limit for this reason. Speeds over the limit only show a sad face.

The devices seem to be mostly ignored anyway.