Hi The controller shown on the PC board is not a chopper. The only reason you would be getting 60 Hz is that somebody did an “aw shucks” and left a part off the board. I suppose they could have left a part off (or put the wrong part on) on whole batch of them. I’d make sure it still does it with a big bypass (100 uF tantalum) on the supply right at the OCXO before I gave up on the parts.
Given that it’s China, those parts may not have any relation at all to the CTS we think of over here (regardless of how they are labeled). Internal workmanship and design suggests that they did come from CTS. Bob > On Feb 27, 2016, at 12:35 PM, Rob Sherwood. <[email protected]> wrote: > > Hi Dan, > > I purchased two of these, and VA7OJ one. One of mine is defective, and the > seller is going to replace it. What was disappointing was all the spurious > at 60 Hz intervals relatively close-in to the 10 MHz carrier. I suppose if > all one wants is a reasonably accurate 10 MHz, then they work OK. My good > one and Adam's unit were 1x10^7 low in frequency once warmed up, and there > are pins for frequency adjustment and sync to another standard. However if > one wanted it for an oscillator with good close-in phase noise, the spurs > ruin that hope. > > Do you know if there is a chopper at 60 Hz that runs the proportional oven > that is the source of all the spurious? > > Rob > NC0B > > -----Original Message----- > From: time-nuts [mailto:[email protected]] On Behalf Of Daniel Watson > Sent: Saturday, February 27, 2016 9:48 AM > To: [email protected] > Subject: [time-nuts] Inside a CTS 1960017 OCXO > > > > Hi, > > I'm sure many of you are tracking the cheap CTS 10MHz OCXOs available on eBay > right now. I purchased a case of them, and decided to crack one open. > I took pictures along the way, thinking that might be interesting to the > list. Here is the blog post if you are interested: > > http://syncchannel.blogspot.com/2016/02/10mhz-ocxo-teardown-cts-1960017.html > > Comments on the internal construction of the OCXO are welcome. It seems > pretty straightforward inside though. > > > Best regards, > > Dan W. > _______________________________________________ > time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > > -- > If this email is spam, report it to > https://support.onlymyemail.com/view/report_spam/ODExMjI6MTg1NzM0MDA3NTpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
