Say I have to measure several dozen 2-pin xtal cans, 4.00 Mhz to 80.00 Mhz. They need to be checked for accuracy. All are hot-swappable in a 5v based DIY driver ckt. (see photo). This works very well.
But where I run into weird issues is when the same xtal is in the ckt they are intended to be used. Say an audio D/A, DVD player or CD player. Measurement in situ , with xtal across an IC's X_in to X_out "driver pins" gives all sorts of distorted or inaccurate readings; perhaps, only the old Tek 465 is most reliable and repeatable for xtals in circuit.
What I have to measure:
I have an old-school but calibrated Tek 465, a modern Siglent 1202x-e dso, NanoVNA, NanaoSA, Owon xdm2041 desktop dmm, and Koolertron DDS sig gen/counter.
Does anyone have preferences?
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Test jig:
Works well even with simple DDS counter:
But here's where I run into issues (e.g., measuring in circuit, with xtal driven by microprocessor's X_in/X_out pins. I get no or garbage readings when probing at X_in or X_out -- with dso, dds, dmm, NanoSA, etc):
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When using the 465 do you use the "CH1 vert sig out" to feed your frequency counter?
Before my 7613 failed, I found that very convenient with my less than stellar frequency counter, as it provided a controllable gain buffer with built in waveform display----you can't get much better than that!
In most of the crystal oscillator stages I've looked at, I have just placed the 'scope probe in close proximity to the metal body of the crystal package.
There is usually enough pickup, but if it is a bit minimal, I rest the outside of the "witch's hat against the body.
As there is no real direct connection, I often used "x1"probes.
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