Re: [time-nuts] Inside a CTS 1960017 OCXO
Interesting in that the internal construction is similar to the 5.55MHz CTS OCXO opened (with a propane torch - nothing inside can was damaged) to deduce out the pinout and the supply voltage.Oscillator circuit was similar although the output buffer was a CMOS flipflop that divided the oscillator frequency by 2. Output was 5V CMOS level. The BSV52 is normally intended to be used as a fast saturated switch in that its storage time is only a few (13) ns. Traditionally gold doping (although caesium is another possibility) is used to achieve a sufficiently low minority carrier lifetime.Gold doping reduces current gain and usually increases the low frequency noise. If you open a few more OCXOs you will find that a lot of the newer ones use a CMOS chip as the output buffer even with a sine output. Bruce On Friday, 4 March 2016 3:03 PM, Daniel Watson wrote: Hi all, I worked out the schematic for the CTS OCXO. You can find it here: http://syncchannel.blogspot.com/2016/03/schematic-of-cts-1960017-10mhz-ocxo..html Best regards, Dan W. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi all, I worked out the schematic for the CTS OCXO. You can find it here: http://syncchannel.blogspot.com/2016/03/schematic-of-cts-1960017-10mhz-ocxo.html Best regards, Dan W. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Bob, I was referring to the bulk of the conversations on this device where people were finding 60 Hz related artifacts. Greg >On Date: Mon, 29 Feb 2016 21:11:19 -0500 >From: Bob Camp wrote: > >Hi > >On some parts the spur shows up in the 40 to 80 Hz range. >That pretty much rules out the line frequency. > >Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi The spectrum plots and scope plots do not look like a blocking oscillator. They look very much like an internal spur generated by something in the circuit taking off at low frequency. Bob > On Mar 1, 2016, at 10:09 AM, Alex Pummer wrote: > > sometimes high frequency oscillators could get in certain mode of operation > the "blocking oscillation" see here: > https://en.wikipedia.org/wiki/Blocking_oscillator, also it could happen, that > the high frequency oscillation does not stops entirely, just undergoes an > amplitude fluctuation, that could cause side bands on both side of the > carrier. Blocking oscillation could happen because of to strong positive > feedback -- due to design error or component error. The dumping of that > product on e-Bay also could be a sign of a to late recognized error > 73 > KJ6UHN > > On 2/29/2016 2:04 PM, Gregory Muir wrote: >> Not sure if I am missing something here or not but an early mention was made >> regarding synching the test equipment used to the 60 Hz line to see if the >> purported 60 Hz anomaly is actually synchronous or asynchronous. I haven't >> heard anything regarding this since then. >> >> Greg >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> - >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2016.0.7442 / Virus Database: 4537/11724 - Release Date: 03/01/16 > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
sometimes high frequency oscillators could get in certain mode of operation the "blocking oscillation" see here: https://en.wikipedia.org/wiki/Blocking_oscillator, also it could happen, that the high frequency oscillation does not stops entirely, just undergoes an amplitude fluctuation, that could cause side bands on both side of the carrier. Blocking oscillation could happen because of to strong positive feedback -- due to design error or component error. The dumping of that product on e-Bay also could be a sign of a to late recognized error 73 KJ6UHN On 2/29/2016 2:04 PM, Gregory Muir wrote: Not sure if I am missing something here or not but an early mention was made regarding synching the test equipment used to the 60 Hz line to see if the purported 60 Hz anomaly is actually synchronous or asynchronous. I haven't heard anything regarding this since then. Greg ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. - No virus found in this message. Checked by AVG - www.avg.com Version: 2016.0.7442 / Virus Database: 4537/11724 - Release Date: 03/01/16 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi On some parts the spur shows up in the 40 to 80 Hz range. That pretty much rules out the line frequency. Bob > On Feb 29, 2016, at 5:04 PM, Gregory Muir wrote: > > Not sure if I am missing something here or not but an early mention was made > regarding synching the test equipment used to the 60 Hz line to see if the > purported 60 Hz anomaly is actually synchronous or asynchronous. I haven't > heard anything regarding this since then. > > Greg > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Not sure if I am missing something here or not but an early mention was made regarding synching the test equipment used to the 60 Hz line to see if the purported 60 Hz anomaly is actually synchronous or asynchronous. I haven't heard anything regarding this since then. Greg ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
I have two Perseus, one in my Denver lab and one on loan to N0QO. Adam in Canada has his own Perseus, CTS module and some other lab supply. It looks like one of the disassembled CTS modules also has spurs in the 40 to 70-Hz range. Some kind of oscillation. I'll get back to this issue after some other projects are finished. Rob NC0B Sent from my iPad > On Feb 29, 2016, at 1:01 PM, "Tom Holmes" wrote: > > > > Rob... > > Are you and Adam using the same Perseus receiver for your measurements? > > Have you looked at another similar type (as in small PCB configuration) and > powered (as in from your HP supply) oscillator for comparison? > > Not to beat the PS question to death, but does a battery supply change the > outcome? > > Tom Holmes, N8ZM > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Rob Sherwood. > Sent: Saturday, February 27, 2016 7:20 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > Both Adam and I measure the same spurs. Rob, NC0B > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Graham / KE9H > Sent: Saturday, February 27, 2016 2:08 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > > > Rob: > Are you sure you were running it with a clean power supply? > Any 60 Hz ripple on the supply could show up as AM/PM modulation. > You might want to try another 5V power supply before you give up on the > oscillator. > --- Graham > > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > 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/ODExMjI6MTg1NzgyNDQzNDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Rob... Are you and Adam using the same Perseus receiver for your measurements? Have you looked at another similar type (as in small PCB configuration) and powered (as in from your HP supply) oscillator for comparison? Not to beat the PS question to death, but does a battery supply change the outcome? Tom Holmes, N8ZM -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Rob Sherwood. Sent: Saturday, February 27, 2016 7:20 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO Both Adam and I measure the same spurs. Rob, NC0B -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Graham / KE9H Sent: Saturday, February 27, 2016 2:08 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO Rob: Are you sure you were running it with a clean power supply? Any 60 Hz ripple on the supply could show up as AM/PM modulation. You might want to try another 5V power supply before you give up on the oscillator. --- Graham ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Pretty much agree with Dave M. But just like HP, PDI had their basic supplies and their 'low noise/ripple' models, and of course the model with the heater for voltage stability. The one Dave is talking about has a temp controlled voltage reference. The easiest way to tell is there is a 'HEATER' light on the front panel. I'll toss in a 3rd company, Kepco. So for me its PDI, Kepco, and a HP. Sounds like I should finish that web page I started of the low noise/ripple models from the three makes. On Sun, Feb 28, 2016 at 7:25 PM, Dave M wrote: > Pete Lancashire wrote: > >> ... I was using an HP lab supply>>> >> >> Model ? Age ? >> >> My bench has some pretty old HP's even Harrison Lab branded supplies. >> I >> have had to re-cap a few of them. >> In a way it is almost a curse how reliable their supplies were. You >> always got the V and I you wanted so one >> never thought about the filtering getting worse over the years. >> >> Also HP had two variations of their bench supplies. The basic ones >> and the low noise versions. When I need >> to make measurement like this, I make sure I'm using one of the low >> noise/ripple models. >> >> > Adding my few cents' worth to the power supply ripple/noise thoughts, I've > found that the old linear supplies by Power Designs Inc were among the > best, at considerably lower cost than the HP/Harrison Labs units. > Ripple/Noise in the low millivolts and high microvolts, 0.01 - 0.005% > regulation and temperature stability in the neighborhood of 0.01%/degC were > common. > I have a couple on my bench, and they just keep on working. They still > pop up at auction frequently. > > Cheers, > Dave M > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi For a lot of years the Power Designs supplies were the best kept secret in the business. Everybody thought they had “discovered” them for phase noise testing. They still are a pretty good deal surplus. Bob > On Feb 28, 2016, at 10:25 PM, Dave M wrote: > > Pete Lancashire wrote: >> ... I was using an HP lab supply>>> >> >> Model ? Age ? >> >> My bench has some pretty old HP's even Harrison Lab branded supplies. >> I >> have had to re-cap a few of them. >> In a way it is almost a curse how reliable their supplies were. You >> always got the V and I you wanted so one >> never thought about the filtering getting worse over the years. >> >> Also HP had two variations of their bench supplies. The basic ones >> and the low noise versions. When I need >> to make measurement like this, I make sure I'm using one of the low >> noise/ripple models. >> > > Adding my few cents' worth to the power supply ripple/noise thoughts, I've > found that the old linear supplies by Power Designs Inc were among the best, > at considerably lower cost than the HP/Harrison Labs units. > Ripple/Noise in the low millivolts and high microvolts, 0.01 - 0.005% > regulation and temperature stability in the neighborhood of 0.01%/degC were > common. > I have a couple on my bench, and they just keep on working. They still pop > up at auction frequently. > > Cheers, > Dave M > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
My T-bolt is running on a Power-one International Series HCAS-60W-A supply, hefty enough to run at least 4 more. Ripple and noise measure less than 100 micro-volts peak-to-peak. The T-bolt seems quite happy. Jeremy On Sunday, February 28, 2016, Dave M wrote: > Pete Lancashire wrote: > >> ... I was using an HP lab supply>>> >> >> Model ? Age ? >> >> My bench has some pretty old HP's even Harrison Lab branded supplies. >> I >> have had to re-cap a few of them. >> In a way it is almost a curse how reliable their supplies were. You >> always got the V and I you wanted so one >> never thought about the filtering getting worse over the years. >> >> Also HP had two variations of their bench supplies. The basic ones >> and the low noise versions. When I need >> to make measurement like this, I make sure I'm using one of the low >> noise/ripple models. >> >> > Adding my few cents' worth to the power supply ripple/noise thoughts, I've > found that the old linear supplies by Power Designs Inc were among the > best, at considerably lower cost than the HP/Harrison Labs units. > Ripple/Noise in the low millivolts and high microvolts, 0.01 - 0.005% > regulation and temperature stability in the neighborhood of 0.01%/degC were > common. > I have a couple on my bench, and they just keep on working. They still > pop up at auction frequently. > > Cheers, > Dave M > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Sent from Gmail Mobile ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Pete Lancashire wrote: ... I was using an HP lab supply>>> Model ? Age ? My bench has some pretty old HP's even Harrison Lab branded supplies. I have had to re-cap a few of them. In a way it is almost a curse how reliable their supplies were. You always got the V and I you wanted so one never thought about the filtering getting worse over the years. Also HP had two variations of their bench supplies. The basic ones and the low noise versions. When I need to make measurement like this, I make sure I'm using one of the low noise/ripple models. Adding my few cents' worth to the power supply ripple/noise thoughts, I've found that the old linear supplies by Power Designs Inc were among the best, at considerably lower cost than the HP/Harrison Labs units. Ripple/Noise in the low millivolts and high microvolts, 0.01 - 0.005% regulation and temperature stability in the neighborhood of 0.01%/degC were common. I have a couple on my bench, and they just keep on working. They still pop up at auction frequently. Cheers, Dave M ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi We have at least one example of the spurs being in the 40 to 80 Hz range “depending”. That strongly suggests that the original analysis is correct and that it is a spur in the OCXO rather than line noise induced issues in a test setup. Bob > On Feb 28, 2016, at 5:49 PM, Bill Byrom wrote: > > If the spurs are at exactly 60 Hz multiples (not 120 Hz or 180 Hz) and > you are in an area with 60 Hz line power you might have magnetic field > coupling from nearby power transformers. Normal conductive shielding > won't solve this issue, and Mu-Metal or other high permeability low > frequency materials must be used. The voltage induced in ground loops by > AC magnetic field depends on the area enclosed by the loop, so twisting > wiring can help in some cases. > > I suggest a test as follows: > * If possible, move the DUT (device under test) to an area which is at > least a couple of meters from AC mains power lines and transformers > connected to AC mains power. Power the DUT from a battery based > supply. Keep any galvanic connection (any conductive wires or metal > cases touching metal benches) away from the DUT, except a single > safety ground wire. > * If that's not easy (and I don't that level of isolation is practical > for most of us), then turn off all AC mains line powered equipment > within a couple of meters of the DUT. Unplug all equipment nearby > from the AC mains power line, then plug the power supply used by the > DUT and the minimum test equipment required for the 60 Hz spur test > into a single quality AC power strip. This single AC power strip > (with only the DUT supply and critical test equipment) should be the > only item plugged into the nearby AC mains power sockets. Using a > single quality power strip will establish a safety wire ground which > is nearly a single point ground. In some buildings there can be > problems if the safety ground wires for different AC mains line > sockets have different potentials due to connected equipment or water > pipe or other external connections. > * Keep any transformers which are plugged into the AC mains line power > as far as possible from the DUT and the connections between the power > supply, DUT, and any test equipment. > * Be sure to turn off any nearby AC mains line powered lighting in the > area and see if that changes the spurs. > * Connect a heavy gauge (such as #10) copper wire between the metal > chassis or other ground point on the test equipment, power supply, > and DUT and see if the spur level changes. If it does, then you have > ground loop problems. The effective source impedance of magnetically > coupled currents is very low, so it can be difficult to eliminate > them completely. Single point ground systems are usually a good idea. > -- > Bill Byrom N5BB > > > > On Sun, Feb 28, 2016, at 12:22 PM, Adrian Godwin wrote: >> Could it be microphonic capacitors, or the crystal itself ? >> Have you got a big old heavy power supply with a buzzing transformer on >> your workbench ? >> > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
If the spurs are at exactly 60 Hz multiples (not 120 Hz or 180 Hz) and you are in an area with 60 Hz line power you might have magnetic field coupling from nearby power transformers. Normal conductive shielding won't solve this issue, and Mu-Metal or other high permeability low frequency materials must be used. The voltage induced in ground loops by AC magnetic field depends on the area enclosed by the loop, so twisting wiring can help in some cases. I suggest a test as follows: * If possible, move the DUT (device under test) to an area which is at least a couple of meters from AC mains power lines and transformers connected to AC mains power. Power the DUT from a battery based supply. Keep any galvanic connection (any conductive wires or metal cases touching metal benches) away from the DUT, except a single safety ground wire. * If that's not easy (and I don't that level of isolation is practical for most of us), then turn off all AC mains line powered equipment within a couple of meters of the DUT. Unplug all equipment nearby from the AC mains power line, then plug the power supply used by the DUT and the minimum test equipment required for the 60 Hz spur test into a single quality AC power strip. This single AC power strip (with only the DUT supply and critical test equipment) should be the only item plugged into the nearby AC mains power sockets. Using a single quality power strip will establish a safety wire ground which is nearly a single point ground. In some buildings there can be problems if the safety ground wires for different AC mains line sockets have different potentials due to connected equipment or water pipe or other external connections. * Keep any transformers which are plugged into the AC mains line power as far as possible from the DUT and the connections between the power supply, DUT, and any test equipment. * Be sure to turn off any nearby AC mains line powered lighting in the area and see if that changes the spurs. * Connect a heavy gauge (such as #10) copper wire between the metal chassis or other ground point on the test equipment, power supply, and DUT and see if the spur level changes. If it does, then you have ground loop problems. The effective source impedance of magnetically coupled currents is very low, so it can be difficult to eliminate them completely. Single point ground systems are usually a good idea. -- Bill Byrom N5BB On Sun, Feb 28, 2016, at 12:22 PM, Adrian Godwin wrote: > Could it be microphonic capacitors, or the crystal itself ? > Have you got a big old heavy power supply with a buzzing transformer on > your workbench ? > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
... I was using an HP lab supply>>> Model ? Age ? My bench has some pretty old HP's even Harrison Lab branded supplies. I have had to re-cap a few of them. In a way it is almost a curse how reliable their supplies were. You always got the V and I you wanted so one never thought about the filtering getting worse over the years. Also HP had two variations of their bench supplies. The basic ones and the low noise versions. When I need to make measurement like this, I make sure I'm using one of the low noise/ripple models. Another thing that is pretty easy to eliminate is radiated 60 Hz. Build a cell (box). A very simple disposable one can be from a corrugated box, aluminum foil, and a few feed through connections. Any lighting not based on piece of tungsten wire ? On Sat, Feb 27, 2016 at 1:07 PM, Rob Sherwood. wrote: > I cannot say exactly, as I measured it as 59 Hz. VA7OJ measured it as 60 > Hz. I was using an HP lab supply, and Adam was using some other lab > supply. I put a 500 uF capacitor across the Vcc pin and it had no effect. > I don't think it has anything to do with the power supply since both of us > saw the same thing. If an attachment will go through this reflector, I can > post a spectrum analyzer screen shot. > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of jimlux > Sent: Saturday, February 27, 2016 12:07 PM > To: time-nuts@febo.com > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > > > On 2/27/16 9:35 AM, Rob Sherwood. 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? > > > > > Is it right at line frequency, or is it "close" to 60 Hz? > > ___ > time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM3NjQ1Mzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Could it be microphonic capacitors, or the crystal itself ? Have you got a big old heavy power supply with a buzzing transformer on your workbench ? On Sun, Feb 28, 2016 at 3:04 PM, Daniel Watson wrote: > Hi, > > I put one in a freezer and measured the current draw. At -12*C, it drew > about 320 mA steady state (1.6W). > > Dan > > On Sat, Feb 27, 2016 at 7:30 PM, Rob Sherwood. wrote: > > > The part draws 600 mA during warm-up, and drops to around 230 to 200 mA > > when stabilized. > > Rob > > NC0B > > > > -Original Message- > > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob > Camp > > Sent: Saturday, February 27, 2016 2:26 PM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > > > > > > > Hi > > > > A small air gap is actually a better insulator than conventional foam. > You > > don’t get much of a convection cell going at those spacings. The part > > likely pulls a bit over a watt at room. > > > > If you put an insulator on the gizmo you increase it’s thermal gain. That > > will most likely make the temperature performance significantly worse. > See > > the good old papers on the HP super ovens for all the details. > > > > Bob > > > > > On Feb 27, 2016, at 12:44 PM, Tom Miller > > wrote: > > > > > > > > > - Original Message - From: "Daniel Watson" > > > > > > To: > > > Sent: Saturday, February 27, 2016 11:48 AM > > > 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-19600 > > >> 17.html > > >> > > >> Comments on the internal construction of the OCXO are welcome. It > > >> seems pretty straightforward inside though. > > >> > > >> > > >> Best regards, > > >> > > >> Dan W. > > > > > > Looks like it would use a lot of power in a cold environment. Maybe a > > second oven would be nice. They seem to have marked the turnover temp on > > the xtal. > > > > > > Regards > > > ___ > > > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM5Mjc1MDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi, I put one in a freezer and measured the current draw. At -12*C, it drew about 320 mA steady state (1.6W). Dan On Sat, Feb 27, 2016 at 7:30 PM, Rob Sherwood. wrote: > The part draws 600 mA during warm-up, and drops to around 230 to 200 mA > when stabilized. > Rob > NC0B > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp > Sent: Saturday, February 27, 2016 2:26 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > > > Hi > > A small air gap is actually a better insulator than conventional foam. You > don’t get much of a convection cell going at those spacings. The part > likely pulls a bit over a watt at room. > > If you put an insulator on the gizmo you increase it’s thermal gain. That > will most likely make the temperature performance significantly worse. See > the good old papers on the HP super ovens for all the details. > > Bob > > > On Feb 27, 2016, at 12:44 PM, Tom Miller > wrote: > > > > > > - Original Message - From: "Daniel Watson" > > > > To: > > Sent: Saturday, February 27, 2016 11:48 AM > > 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-19600 > >> 17.html > >> > >> Comments on the internal construction of the OCXO are welcome. It > >> seems pretty straightforward inside though. > >> > >> > >> Best regards, > >> > >> Dan W. > > > > Looks like it would use a lot of power in a cold environment. Maybe a > second oven would be nice. They seem to have marked the turnover temp on > the xtal. > > > > Regards > > ___ > > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM5Mjc1MDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi Dan how many of these oscillators have that low freq.hum? 73 KJ6UHN Alex On 2/27/2016 6:25 PM, Daniel Watson wrote: Hi, Attached is a plot of the output frequency difference from 10MHz during warm-up. I believe this indicates the crystal is SC cut. The VREF and EFC pins on the unit do work. The VREF is 4.1V. I probed around the board of the unit I cracked open and found a low frequency oscillation. It seems to vary from 40 to 90 Hz depending on where the unit is in the warm-up cycle, and what I'm doing to it. With the can cut off, the unit draws almost 50% more power than normal trying to maintain temperature, so it's possible this is offset from what has been reported in normal units. In the photos, you may have noticed two sets of large, unpopulated pads on the board near the output. I experimented with putting 10uF capacitors across those. That killed the output, but the low frequency oscillation could still be detected further back in the circuit. Dan On Sat, Feb 27, 2016 at 1:10 PM, Joseph Gray wrote: Nice teardown. I was looking at that listing just yesterday. I am tempted, but don't know what I'd do with 40. The real question is, how do they perform? Joe Gray W5JG On Feb 27, 2016 9:48 AM, "Daniel Watson" wrote: 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 -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. - No virus found in this message. Checked by AVG - www.avg.com Version: 2016.0.7442 / Virus Database: 4537/11711 - Release Date: 02/27/16 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
The part draws 600 mA during warm-up, and drops to around 230 to 200 mA when stabilized. Rob NC0B -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Saturday, February 27, 2016 2:26 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO Hi A small air gap is actually a better insulator than conventional foam. You don’t get much of a convection cell going at those spacings. The part likely pulls a bit over a watt at room. If you put an insulator on the gizmo you increase it’s thermal gain. That will most likely make the temperature performance significantly worse. See the good old papers on the HP super ovens for all the details. Bob > On Feb 27, 2016, at 12:44 PM, Tom Miller wrote: > > > - Original Message - From: "Daniel Watson" > > To: > Sent: Saturday, February 27, 2016 11:48 AM > 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-19600 >> 17.html >> >> Comments on the internal construction of the OCXO are welcome. It >> seems pretty straightforward inside though. >> >> >> Best regards, >> >> Dan W. > > Looks like it would use a lot of power in a cold environment. Maybe a second > oven would be nice. They seem to have marked the turnover temp on the xtal. > > Regards > ___ > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM5Mjc1MDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
I would have to make the measurement again with the HP supply off. I have measured my Rubidium and my GPSDO and never seen anything like this spectra of close-spaced spurious. I'll send you some more data direct. Rob NC0B -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Saturday, February 27, 2016 3:32 PM To: Discussion of precise time and frequency measurement Cc: hmur...@megapathdsl.net Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO r...@nc0b.com said: > I cannot say exactly, as I measured it as 59 Hz. VA7OJ measured it as > 60 Hz. I was using an HP lab supply, and Adam was using some other lab > supply. > I put a 500 uF capacitor across the Vcc pin and it had no effect. I > don't think it has anything to do with the power supply since both of > us saw the same thing. ... How much line noise is floating around the lab? What does the spectrum analyzer see if you power off the DUT? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM5OTk5ODpyb2JAbmMwYi5jb206ZGVsaXZlcmVk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi, Attached is a plot of the output frequency difference from 10MHz during warm-up. I believe this indicates the crystal is SC cut. The VREF and EFC pins on the unit do work. The VREF is 4.1V. I probed around the board of the unit I cracked open and found a low frequency oscillation. It seems to vary from 40 to 90 Hz depending on where the unit is in the warm-up cycle, and what I'm doing to it. With the can cut off, the unit draws almost 50% more power than normal trying to maintain temperature, so it's possible this is offset from what has been reported in normal units. In the photos, you may have noticed two sets of large, unpopulated pads on the board near the output. I experimented with putting 10uF capacitors across those. That killed the output, but the low frequency oscillation could still be detected further back in the circuit. Dan On Sat, Feb 27, 2016 at 1:10 PM, Joseph Gray wrote: > Nice teardown. I was looking at that listing just yesterday. I am tempted, > but don't know what I'd do with 40. > > The real question is, how do they perform? > > Joe Gray > W5JG > On Feb 27, 2016 9:48 AM, "Daniel Watson" wrote: > > > 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 -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Both Adam and I measure the same spurs. Rob, NC0B -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Graham / KE9H Sent: Saturday, February 27, 2016 2:08 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO Rob: Are you sure you were running it with a clean power supply? Any 60 Hz ripple on the supply could show up as AM/PM modulation. You might want to try another 5V power supply before you give up on the oscillator. --- Graham On Sat, Feb 27, 2016 at 11:35 AM, Rob Sherwood. 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:time-nuts-boun...@febo.com] On Behalf Of > Daniel Watson > Sent: Saturday, February 27, 2016 9:48 AM > To: time-nuts@febo.com > 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-196001 > 7.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 -- time-nuts@febo.com 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/ODExMjI6MTg1NzM0MDA3N > Tpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > ___ > time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM4NTM3Nzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
A metal shield provides to aspects, firstly it will act as a windshield and keep some air confined and secondly, it will help equalize the temperature surrounding the oven such that it itself reduces temperature gradients, simply by being a better conductor of heat than the air. You still have black-body convection for sure. For lesser oscillators, just putting a small plastic hut over the crystal have improved things greatly. Cheers, Magnus On 02/27/2016 10:25 PM, Bob Camp wrote: Hi A small air gap is actually a better insulator than conventional foam. You don’t get much of a convection cell going at those spacings. The part likely pulls a bit over a watt at room. If you put an insulator on the gizmo you increase it’s thermal gain. That will most likely make the temperature performance significantly worse. See the good old papers on the HP super ovens for all the details. Bob On Feb 27, 2016, at 12:44 PM, Tom Miller wrote: - Original Message - From: "Daniel Watson" To: Sent: Saturday, February 27, 2016 11:48 AM 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. Looks like it would use a lot of power in a cold environment. Maybe a second oven would be nice. They seem to have marked the turnover temp on the xtal. Regards ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
r...@nc0b.com said: > I cannot say exactly, as I measured it as 59 Hz. VA7OJ measured it as 60 > Hz. I was using an HP lab supply, and Adam was using some other lab supply. > I put a 500 uF capacitor across the Vcc pin and it had no effect. I don't > think it has anything to do with the power supply since both of us saw the > same thing. ... How much line noise is floating around the lab? What does the spectrum analyzer see if you power off the DUT? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi Ok, so that’s phase modulation and not frequency modulation. Simply put, it’s not a high level signal into the EFC. It’s also not anything inside the oscillator loop. Normally the best way to do a broadband phase mod like that is to feed a signal into the input of the output buffer. I’d check it with a couple of different loads and see if that chip sings when loaded this way vs that way. Bob > On Feb 27, 2016, at 4:18 PM, Rob Sherwood. wrote: > > Here is a look at the spectra. 6.3 kHz span, 7.6 kHz resolution bandwidth. > I have a 1.6 MB file with better resolution, but I assumed that would never > make it through the reflector. > Rob > NC0B > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp > Sent: Saturday, February 27, 2016 12:25 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO > > > > 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. 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:time-nuts-boun...@febo.com] On Behalf Of >> Daniel Watson >> Sent: Saturday, February 27, 2016 9:48 AM >> To: time-nuts@febo.com >> 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-196001 >> 7.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 -- time-nuts@febo.com 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/ODExMjI6MTg1NzM0MDA3N >> Tpyb2JAbmMwYi5jb206ZGVsaXZlcmVk >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM3NjUwNDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Line frequency is suspicious from either power supply or measurement system standpoint. Sent via the Samsung Galaxy S®6 active, an AT&T 4G LTE smartphone Original message From: "Rob Sherwood." Date: 2/27/2016 1:07 PM (GMT-08:00) To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO I cannot say exactly, as I measured it as 59 Hz. VA7OJ measured it as 60 Hz. I was using an HP lab supply, and Adam was using some other lab supply. I put a 500 uF capacitor across the Vcc pin and it had no effect. I don't think it has anything to do with the power supply since both of us saw the same thing. If an attachment will go through this reflector, I can post a spectrum analyzer screen shot. -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of jimlux Sent: Saturday, February 27, 2016 12:07 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO On 2/27/16 9:35 AM, Rob Sherwood. 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? > Is it right at line frequency, or is it "close" to 60 Hz? ___ time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM3NjQ1Mzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi A small air gap is actually a better insulator than conventional foam. You don’t get much of a convection cell going at those spacings. The part likely pulls a bit over a watt at room. If you put an insulator on the gizmo you increase it’s thermal gain. That will most likely make the temperature performance significantly worse. See the good old papers on the HP super ovens for all the details. Bob > On Feb 27, 2016, at 12:44 PM, Tom Miller wrote: > > > - Original Message - From: "Daniel Watson" > To: > Sent: Saturday, February 27, 2016 11:48 AM > 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. > > Looks like it would use a lot of power in a cold environment. Maybe a second > oven would be nice. They seem to have marked the turnover temp on the xtal. > > Regards > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
I cannot say exactly, as I measured it as 59 Hz. VA7OJ measured it as 60 Hz. I was using an HP lab supply, and Adam was using some other lab supply. I put a 500 uF capacitor across the Vcc pin and it had no effect. I don't think it has anything to do with the power supply since both of us saw the same thing. If an attachment will go through this reflector, I can post a spectrum analyzer screen shot. -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of jimlux Sent: Saturday, February 27, 2016 12:07 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Inside a CTS 1960017 OCXO On 2/27/16 9:35 AM, Rob Sherwood. 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? > Is it right at line frequency, or is it "close" to 60 Hz? ___ time-nuts mailing list -- time-nuts@febo.com 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/ODExMjI6MTg1NzM3NjQ1Mzpyb2JAbmMwYi5jb206ZGVsaXZlcmVk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Rob: Are you sure you were running it with a clean power supply? Any 60 Hz ripple on the supply could show up as AM/PM modulation. You might want to try another 5V power supply before you give up on the oscillator. --- Graham On Sat, Feb 27, 2016 at 11:35 AM, Rob Sherwood. 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:time-nuts-boun...@febo.com] On Behalf Of Daniel > Watson > Sent: Saturday, February 27, 2016 9:48 AM > To: time-nuts@febo.com > 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 -- time-nuts@febo.com 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 -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Hi I believe you will find that the crystal in the picture is either an HC-45 or HC-43 sized package. Bob > On Feb 27, 2016, at 12:17 PM, Graham / KE9H wrote: > > Dan: > > Thanks for photo documenting the tear down of the CTS oven oscillators. > I bought a few, and was interested in what was inside. > I was surprised to see an HC-6 style crystal, but at least it was a > cold-weld case. > > I note that you did some design work for Adafruit. > Curiosity question: > Did they solicit you, or did you solicit them for the work? > Or did they just see and copy your stuff on Oshpark? > > --- Graham / KE9H > > On Sat, Feb 27, 2016 at 10:48 AM, Daniel Watson > wrote: > >> 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 -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
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. 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:time-nuts-boun...@febo.com] On Behalf Of Daniel Watson > Sent: Saturday, February 27, 2016 9:48 AM > To: time-nuts@febo.com > 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 -- time-nuts@febo.com 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 -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
On 2/27/16 9:35 AM, Rob Sherwood. 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? Is it right at line frequency, or is it "close" to 60 Hz? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
- Original Message - From: "Daniel Watson" To: Sent: Saturday, February 27, 2016 11:48 AM 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. Looks like it would use a lot of power in a cold environment. Maybe a second oven would be nice. They seem to have marked the turnover temp on the xtal. Regards ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
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:time-nuts-boun...@febo.com] On Behalf Of Daniel Watson Sent: Saturday, February 27, 2016 9:48 AM To: time-nuts@febo.com 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 -- time-nuts@febo.com 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 -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Nice teardown. I was looking at that listing just yesterday. I am tempted, but don't know what I'd do with 40. The real question is, how do they perform? Joe Gray W5JG On Feb 27, 2016 9:48 AM, "Daniel Watson" wrote: > 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 -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Inside a CTS 1960017 OCXO
Dan: Thanks for photo documenting the tear down of the CTS oven oscillators. I bought a few, and was interested in what was inside. I was surprised to see an HC-6 style crystal, but at least it was a cold-weld case. I note that you did some design work for Adafruit. Curiosity question: Did they solicit you, or did you solicit them for the work? Or did they just see and copy your stuff on Oshpark? --- Graham / KE9H On Sat, Feb 27, 2016 at 10:48 AM, Daniel Watson wrote: > 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 -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
