[time-nuts] Re: Custom Wenzel OXCO with unusual output

[Stewart Cobb]

Generally speaking, these are phase- locked OCXOs.  The way Miteq used
them, the SMA "RF Out" should be the OCXO output. It should be tunable with
the "ET" input. It should be tunable with a trimpot or trimcap hiding
behind the sealing screw on the side. And if you apply an external 5 or 10
MHz signal to the "unmarked" SMA, it should phase lock the internal OCXO to
that external signal. Generally, the external input should be -5 to +10
dBm. Miteq would install these with the external input (usually BNC) and
the mechanical tuning screw sticking out the rear panel of their box.

The one you have may not have been made for Miteq. It may only accept 10
MHz external input. It may be broken internally. Unfortunately, surplus
parts rarely come with specs or provenance.

I have a couple of similar ones with BNC external connectors, that do lock
to external 10 MHz. You never know with surplus. It might help to diddle
the mechanical tuning while watching the output.

Cheers!
--Stu

On Sun, Apr 6, 2025, 11:30 <time-nuts-request at lists.febo.com> wrote:

> Send time-nuts mailing list submissions to
>         time-nuts at lists.febo.com
>
> To subscribe or unsubscribe via email, send a message with subject or
> body 'help' to
>         time-nuts-request at lists.febo.com
>
> You can reach the person managing the list at
>         time-nuts-owner at lists.febo.com
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of time-nuts digest..."
>
> Today's Topics:
>
>    1. Custom Wenzel OXCO with unusual output (Walt)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 1 Apr 2025 11:20:03 -0700
> From: "Walt" <walt at drizzle.com>
> Subject: [time-nuts] Custom Wenzel OXCO with unusual output
> To: "TIME-NUTS LIST POSTING" <time-nuts at lists.febo.com>
> Message-ID: <000201dba332$b0af1c80$120d5580$@drizzle.com>
> Content-Type: multipart/mixed;
>         boundary="----=_NextPart_000_0003_01DBA2F8.04504480"
>
> I picked up a custom Wenzel 500-13248B quartz oscillator and upon measuring
> it, I'm not sure if it is working as designed or what.
>
> The RF Out is a raggedy 10MHz sine wave at 4.4Vpp, and a spectrum analyzer
> shows peaks at 10, 20, 30, 40, 50, 60 and 70 MHz.  There may be more but
> I'm
> not sure how to acquire them.
>
> There is nothing coming out of the second unmarked SMA.
>
> Assuming this is not broken, what kind of oscillator is this, and what
> would
> it be used for?
> -------------- next part --------------
> A message part incompatible with plain text digests has been removed ...
> Name: XO 500-13248B.jpg
> Type: image/jpeg
> Size: 473600 bytes
> Desc: not available
> -------------- next part --------------
> A message part incompatible with plain text digests has been removed ...
> Name: SSA_Peaks.bmp
> Type: image/bmp
> Size: 1843255 bytes
> Desc: not available
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe send an email to time-nuts-leave at lists.febo.com
> %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
>
> ------------------------------
>
> End of time-nuts Digest, Vol 252, Issue 1
> *****************************************
>