Difference between OCXO and TCXO?

[W9KDX]

I am clueless here.  What is the difference, in performance that the user would experience, between a +-0.05 ppm OCXO oven instead of the TCXO oven?  Apparently, the Yaesu FT DX5000MP has the OCXO, while the other version have the TCXO.

Much thanks.

[KQ6EA]

An "OCXO" is an "Oven Controlled Crystal Oscillator" while a "TCXO" is a "Temperature Compensated Crystal Oscillator".
An OCXO *should* have better stability, especially over wide temperature ranges (cold shack in the winter?) while a TCXO is probably good enough for most of us mere mortals.
+/- 0.05ppm from the OCXO +/-would equate to about 1.5Hz at 30MHz, while the +/-0.5ppm from the TCXO would be 15Hz at 30MHz.
Some rigs offer an "Ext Ref In" which would allow you to use something like a GPS disciplined oscillator, or a Rubidium standard for even greater accuracy.
Does it matter?
Probably not at HF frequencies, but if the rig has a "Transverter Output" jack, the the increased accuracy and stability *would* matter if you're using the radio with a microwave transverter.
At 10GHz, the .05ppm oscillator could result in a final frequency error of 500Hz, while the .5ppm oscillator could be off by 5kiloHertz, a significant amount.
Jim

[HB9PJT]

Allmost all HF rigs are connected to a transverter for ordinary radio signal TX and RX paths. But not as a frequency normal. So the transverter has its own local oscillator which determinants the frequency accuracy of the system mainly. In that case a rig without a TCXO or OCXO is more than adequate.

73, Peter - HB99PJT

Does it matter?
Probably not at HF frequencies, but if the rig has a "Transverter Output" jack, the the increased accuracy and stability *would* matter if you're using the radio with a microwave transverter.
At 10GHz, the .05ppm oscillator could result in a final frequency error of 500Hz, while the .5ppm oscillator could be off by 5kiloHertz, a significant amount.
Jim

[W9KDX]

I love the line " for most of us mere mortals".  As I am well into the mere mortal class, I got my answer.

Thanks, what a great resource.