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I want to measure my crystal frequency with oscilloscope. I connect my oscilloscope's ground line to system ground line and my oscilloscope's probe to crystal pin. But ı can not see anything. My crystal's connection is normal connection. Crystal to capacitor, capacitor to ground.

M.P is measure point.

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    \$\begingroup\$ Please edit your question and add a schematic. The schematic editor is very easy to use. \$\endgroup\$
    – TonyM
    Sep 3, 2019 at 18:11
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    \$\begingroup\$ Use a 10x probe. Try both sides of the crystal. One is the output of the oscillator buffer which should give a slightly better signal. \$\endgroup\$
    – Oldfart
    Sep 3, 2019 at 18:22
  • \$\begingroup\$ Indeed, you probably need to use the 10x probe setting to avoid excessively loading the circuit. Another option can be to measure some derived output, for example a timer output or even a serial UART (paying care to the actual baud divider, not the standard baud rate it approximates). Some MCUs have a specifically enable-able clock output. Finally at some clock rates you might be able to use a radio receiver or SDR dongle, on a harmonic of the clock if not the fundamental (the radio would be nearby, but not electrically in contact) \$\endgroup\$ Sep 3, 2019 at 19:25
  • \$\begingroup\$ put the scope on maximum sensitivity; put the bandwidth on maximum; now bring the scope probe tip NEAR but not touching the crystal. \$\endgroup\$ Sep 4, 2019 at 4:03

1 Answer 1

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  1. Check whether power connection is fine
  2. Check the capacitor values
  3. Check the mounting of the three components
  4. Probe both ends
  5. Probably with a active probe if you have one (this will not load the circuit inline normal probes)
  6. If you have a spectrum analyser, keep it in scan mode near the expected crystal frequency and take a wire which can act as antenna and place it very close to the crystal (We use similar methods in production to be non intrusive )
  7. Change the crystal if it is still not functional
  8. If software control is an option, enable the clock on one of the clock output pins OR use it as clock source for ant peripheral and drive it
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