Andrew ZonenbergMar 6

Wrote up the blog-format version of the TCXO failure analysis including a bit more backstory and commentary all in one place

https://serd.es/2026/03/06/TCXO-failure-analysis.html

TCXO failure analysis

Show threadvxoMar 6
@azonenberg
So I guess I'm going to avoid screaming at my TCXOs then
Show threadStewart Russell
@vxo @azonenberg yeah, don't shake the singing rocks
Mar 7 at 3:55pmWeb
Show threadvxoMar 8
@scruss @azonenberg Seems legit. At work we had these Lectrosonics IFB receivers that would often break crystals when dropped hard. What's weird is I've seen Sennheiser stuff survive getting basically used as hockey pucks and surviving multiple HARD impacts that never skipped a beat, but something about the way the Lectros are constructed would murder the crystal.
Show threadStewart RussellMar 8
@vxo it always amazes me that they work at all. Though I do have a 10.000000 MHz OCXO that I think I've managed to fritz entirely by dropping it
Show threadvxoMar 8

@scruss ow!

I have a 10 mhz OCXO as my transfer frequency standard at home, it's a well aged unit. My frequency counter's internal reference is absolute poppycock so I use that with it. My cat appreciates the warmth after it's been powered up about an hour prior to use.

https://www.kg4cyx.net/may-i-just-take-a-microsecond-here/

May I just take a microsecond here

Hey, it’s me, I want to give you some good frequencies. (The part I’m referring to is the very end, and the bandpass filtered beat you hear in the background is the beat to Eple, which …

KG4CYX
Show threadvxoMar 8

@scruss Load-bearing masking tape used during calibration is a phrase I think should be more common because it's hilarious.

But yeah, you can see the OCXO unit itself in the preview pic here - it looks like a distinctly in-house designed thing in a Bud box full of what might actually be fancy ceramic fiber insulation.

Show threadvxoMar 8
@scruss Oh and I guess I could just use the EIP counter too - I was told at one point to make it go away from the storage room, so yeah. :D
Show threadStewart RussellMar 8
@vxo that's quite a nice OCXO. Still annoyed that I missed out on a Rubidium standard when a local ham got a bunch for very cheap years back. Ah well ... I'll never be as cool as the guy I met who had a Shortt Synchronome set up in his office.
Show threadvxoMar 8

@scruss HECK that looks neat

I have a weird thing I bought a few weeks back that might contain some kind of OCXO driven 60 hz reference (!) and has an adorable mechanical clock on the face of it, I've gotta see what's inside it. It even has a receptacle on the back rated for 120V 7 watts. Only use I can imagine that low power output having would be like, driving a strip chart recorder motor

Show threadStewart RussellMar 8
@vxo very neat, is a Synchronome. He was somewhat eccentric: when his work required that everyone senior must have carphones, his phone was worth considerably more than the beat-up Saab 96 it was installed in.
Show threadvxoMar 8
@scruss I swear every time I hear about someone having a Saab they're an eccentric engineer and the car is probably missing about 30 screws
Show threadStewart RussellMar 8

@vxo as long as that one vital screw (most likely a wood screw) is still there, the Saab will hold together. It'll flex a bit, but nothing that Erik "On The Roof" Carlsson couldn't handle

Said engineer was the chief wind turbine designer for many companies. He is why wind turbines spin the direction they do. If he's not fully retired, he's doing something with a carbon capture startup.