Hi,
I've been trying to make a working LC meter for a while now, and I'm pretty close to finishing one now (at least I think). The frequency part works just fine, but the LC part won't do it's job. For the LC part I chose a famous LM311 configuration, but I was reckless enough to skip prototyping it and went on and made a board. Now it won't work of course (LC part, F works just fine). I tried to measure the frequencies with and without the calibration capacitor, and got 0Hz for both of those, so my guess is that the oscillating circuit is somehow faulty.
I've been looking at it for hours, I checked the board for cold joints and I wasn't able to figure out what could possibly be wrong.
Could someone more experienced try to find where I went wrong with the LM311 part?
This is the simplified circuit of the oscillator and frequency counter input circuit.
PS: Don't know if it's relevant, but my design heavily relies on Paul's FreqCount library and uses Arduino instead of PIC.
I've been trying to make a working LC meter for a while now, and I'm pretty close to finishing one now (at least I think). The frequency part works just fine, but the LC part won't do it's job. For the LC part I chose a famous LM311 configuration, but I was reckless enough to skip prototyping it and went on and made a board. Now it won't work of course (LC part, F works just fine). I tried to measure the frequencies with and without the calibration capacitor, and got 0Hz for both of those, so my guess is that the oscillating circuit is somehow faulty.
I've been looking at it for hours, I checked the board for cold joints and I wasn't able to figure out what could possibly be wrong.
Could someone more experienced try to find where I went wrong with the LM311 part?
This is the simplified circuit of the oscillator and frequency counter input circuit.
PS: Don't know if it's relevant, but my design heavily relies on Paul's FreqCount library and uses Arduino instead of PIC.