Timeline for Convert CMOS-level signal to microphone-level (0..3V --> -1..+1V)?
Current License: CC BY-SA 4.0
15 events
| when toggle format | what | by | license | comment | |
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| Oct 17, 2018 at 1:08 | vote | accept | iter | ||
| Oct 8, 2018 at 21:01 | answer | added | Transistor | timeline score: 5 | |
| Oct 8, 2018 at 20:44 | comment | added | iter | Of course the CMOS output from my microcontroller has no zero crossings. I'm trying to generate some for the audio-level signal. I'm unclear on how the specifics of the waveform are relevant to the circuit. If it helps, the waveform is similar to Manchester coding. | |
| Oct 8, 2018 at 20:33 | comment | added | Transistor | Good. The question is approaching "answerable". You didn't clarify my original question "... since the waveform encodes information in zero-crossings." Your 0 to 3 V signal doesn't have zero-crossings. Is it a binary digital stream - e.g., 00010111010110101111 or is it a variable pulse width signal? | |
| Oct 8, 2018 at 20:27 | answer | added | anrieff | timeline score: 1 | |
| Oct 8, 2018 at 20:20 | comment | added | iter | I think what I'm looking for is a kind of MAX232 device, but with lower voltages. | |
| Oct 8, 2018 at 20:20 | history | edited | iter | CC BY-SA 4.0 |
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| Oct 8, 2018 at 20:07 | history | edited | iter | CC BY-SA 4.0 |
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| Oct 8, 2018 at 20:01 | comment | added | iter | It IS very retro, but this technology is making an unexpected comeback. They used to transmit this signal over audio-frequency FM radios. | |
| Oct 8, 2018 at 19:56 | comment | added | Transistor | This seems rather a retro way of doing things (since your original and hope-to-be stored signals are both digital) and reminds me of old telephone modems. The simplest modems worked by transmitting binary zeros and ones using two different audio tones. How much data is to be transmitted in each recording and at what speed? 300 bits per second or 115k? Again, pop all the info into your question rather than in the comments. | |
| Oct 8, 2018 at 19:50 | comment | added | iter | I hop my edit clarifies the requirements some. | |
| Oct 8, 2018 at 19:50 | history | edited | iter | CC BY-SA 4.0 |
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| Oct 8, 2018 at 19:45 | review | First posts | |||
| Oct 8, 2018 at 20:33 | |||||
| Oct 8, 2018 at 19:44 | comment | added | Transistor | Can you edit your question to give a bit more context. For example, are you hoping to reconstitute the original signal by playing back from the audio recording? Also "since the waveform encodes information in zero-crossings" is unclear. What does this mean? | |
| Oct 8, 2018 at 19:41 | history | asked | iter | CC BY-SA 4.0 |