| | Polariod Sonar
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| Hi, I'm stuck. I'm trying to use TTL output of 74 series IC's to signal to INIT. I can't get it to work properly. Here's the deal. When I touch INIT to the 5V bus, the transducer "chirps". But when I touch INIT to a high level TTL output, it doesn't (...) (28 years ago, 23-Nov-96, to lugnet.robotics.handyboard)
| | | | Re: Polariod Sonar
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| (...) Although I teach a digital electronics class based on the 74xx series, I'm certainly no expert, but here goes anyway... TTLs seem to have a very low ability to drive anything but minimal loads. Look up "drivers" in the TTL Data Book. They (...) (28 years ago, 24-Nov-96, to lugnet.robotics.handyboard)
| | | | Re: Polariod Sonar
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| I think you're right. I used a transistor to drive the INIT with its emmiter and feed the TTL signal to the base. It seems to work fine now. :) You know what's funny, I tried using a CMOS chip (HCT) and it was able to drive the INIT signal. I figure (...) (28 years ago, 28-Nov-96, to lugnet.robotics.handyboard)
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