Re: [time-nuts] Trimble Thunderbolt 1pps
On 2014-01-27 23:32, Don Latham wrote: Mike S On 1/27/2014 1:33 PM, Robert Atkinson wrote: I looked at this a while ago. The spec only defines transmission levels, it does NOT specify receive thresholds. It certainly does... 2.1.3 For data interchange circuits, the signal shall be considered in the marking condition when the voltage on the interchange circuit, measured at the interface point, is more negative than -3 volts with respect to Circuit AB (Signal Common). The signal shall be considered in the spacing condition when the voltage is more positive than +3 volts with respect to Circuit AB (see 6.2). The region between +- 3 volts is defined as the transition region. The signal state is undefined when the voltage is in this transition region. - ANSI TIA/EIA-232-F (1997) we, maybe needed if you're running an ASR-33 teletype. . . Except ASR-33s came with a 20ma current loop interface. Later models added RS232 after it became popular. ISTR TWX terminals required one and Telex terminals the other. -- Take care. Thanks, Brian Inglis ___ 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] test after email address change and repost of PRS10 question.
My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike ___ 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] test after email address change and repost of PRS10 question.
Hi Mike, your msg is on the list. Rgds Ernie. -Original Message- From: mike cook michael.c...@sfr.fr To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Tue, Jan 28, 2014 12:14 pm Subject: [time-nuts] test after email address change and repost of PRS10 question. My recent attempts at posting have been all been blocked for some reason so I am witching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock o my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 0ns. I would be grateful, if anyone here has one on their bench, to let me now what theirs is. I can't find any specification in the literature. hanks and have a good day. ike __ ime-nuts mailing list -- time-nuts@febo.com o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd 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] test after email address change and repost of PRS10 question.
My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike 28/01/2014 11:37 Hi Mike. Both messages (the earlier one from the orange.fr address and this one from the sfr.fr address) are showing. If you read the group using e-mail just CC the messages you post back to yourself and filter into the groups folder. Seems Yahoo changed things (again) recently. -- Best Regards, Chris Wilson. ___ 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] test after email address change and repost of PRS10 question.
Time-nuts isn't yahoo. It is something that John Ackermann put together called febo.com. Febo is one of John's cats. Most probably, the OP's email program is set to not display emails which appear to originate from his address... -Chuck Harris Chris Wilson wrote: My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike 28/01/2014 11:37 Hi Mike. Both messages (the earlier one from the orange.fr address and this one from the sfr.fr address) are showing. If you read the group using e-mail just CC the messages you post back to yourself and filter into the groups folder. Seems Yahoo changed things (again) recently. ___ 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] Mini Circuits RF TX question
Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. Thanks, Corby ___ 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] test after email address change and repost of PRS10
My recent attempts at posting have been all been blocked for some Check your options on the mailing list control, there is an option for Receive your own posts to the list? It should default to yet, but perhaps you changed it to no at some point. -- Chris Caudle ___ 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] Mini Circuits RF TX question
Corby, I'd email or call mini-circuits. -John == Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. Thanks, Corby ___ 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] Mini Circuits RF TX question
Hi, try this link http://217.34.103.131/products/Transformers.shtml Rgds Ernie. -Original Message- From: cdelect cdel...@juno.com To: time-nuts time-nuts@febo.com Sent: Tue, Jan 28, 2014 7:28 pm Subject: [time-nuts] Mini Circuits RF TX question Hi, Does anyone know where to find the primary inductance value for Mini ircuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor t 5Mhz. hanks, Corby ___ ime-nuts mailing list -- time-nuts@febo.com o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd 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] Mini Circuits RF TX question
On 1/28/2014 10:26 AM, cdel...@juno.com wrote: Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. At 5 MHz, the core is probably more resistive than inductive and in any event, is not specified for inductance. What I have done in the past is to shunt the transformer with a real inductor. Rick ___ 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] test after email address change and repost of PRS10 question.
Mike, I just measured my FS725 (a PRS10 in a box). The nearest scope was an analog with only 100MHz bandwidth. The PPS risetime was about 5.5ns.The usual analog scope risetime is 0.35/bandwidth so that puts scope risetime around 3.5ns. Whatever the PPS risetime really is, it's an order of magnitude less than your 70ns for sure. Best, Robert. On 28 January 2014 14:30, Chuck Harris cfhar...@erols.com wrote: Time-nuts isn't yahoo. It is something that John Ackermann put together called febo.com. Febo is one of John's cats. Most probably, the OP's email program is set to not display emails which appear to originate from his address... -Chuck Harris Chris Wilson wrote: My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike 28/01/2014 11:37 Hi Mike. Both messages (the earlier one from the orange.fr address and this one from the sfr.fr address) are showing. If you read the group using e-mail just CC the messages you post back to yourself and filter into the groups folder. Seems Yahoo changed things (again) recently. ___ 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] Mini Circuits RF TX question
You might start with a 10.7MHz slug-tuned IF transformer and bring it down with extra padding caps. The spec sheets give winding inductance and suggested tuning cap values. e.g. Mouser 42IF122 and similar is frequently used below 10.7MHz in many designs. Tim N3QE On Tue, Jan 28, 2014 at 1:26 PM, cdel...@juno.com wrote: Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. Thanks, Corby ___ 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] Mini Circuits RF TX question
It isnt going to help I guess but WB transformers for 50ohm are usually designed with a reactance of 150 ohms (3* termination) at the lowest frequency required. It might give an idea where to look?. Alan G3NYK - Original Message - From: cdel...@juno.com To: time-nuts@febo.com Sent: Tuesday, January 28, 2014 6:26 PM Subject: [time-nuts] Mini Circuits RF TX question Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. Thanks, Corby ___ 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] Mini Circuits RF TX question
Hi Normally you design these little gizmos as if they were a common mode choke. The common mode impedance is the design target rather than an inductance. I doubt they have much of a Q at all. The only exception to that would be in the bottom octave of their range. Bob On Jan 28, 2014, at 1:26 PM, cdel...@juno.com wrote: Hi, Does anyone know where to find the primary inductance value for Mini Circuits RF Transformers? I need to know so I can pick one to resonate with a particular capacitor at 5Mhz. Thanks, Corby ___ 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] test after email address change and repost of PRS10 question.
Jarl Risum gave me some info which could explain that. His PRS10 1PPS rise time , taken at the unit DB connector pin, was about 50ns, which is in the same ballpark as mine, but he noted that if the Breaklout Board is installed , the signal passes through a two Schmitt inverters (74HC14s). These might well stiffen it up, having a rise time of 7ns, though adding delay. So if your box has similar interface circuitry that could be it. Thanks for your input. Le 28 janv. 2014 à 19:16, Robert Watson a écrit : Mike, I just measured my FS725 (a PRS10 in a box). The nearest scope was an analog with only 100MHz bandwidth. The PPS risetime was about 5.5ns.The usual analog scope risetime is 0.35/bandwidth so that puts scope risetime around 3.5ns. Whatever the PPS risetime really is, it's an order of magnitude less than your 70ns for sure. Best, Robert. On 28 January 2014 14:30, Chuck Harris cfhar...@erols.com wrote: Time-nuts isn't yahoo. It is something that John Ackermann put together called febo.com. Febo is one of John's cats. Most probably, the OP's email program is set to not display emails which appear to originate from his address... -Chuck Harris Chris Wilson wrote: My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike 28/01/2014 11:37 Hi Mike. Both messages (the earlier one from the orange.fr address and this one from the sfr.fr address) are showing. If you read the group using e-mail just CC the messages you post back to yourself and filter into the groups folder. Seems Yahoo changed things (again) recently. ___ 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] Mini Circuits RF TX question
I agree with Tim - a common 10.7 MHz IF can is close enough, and will provide a nice tuned circuit that you can rough-in with an extra cap, and also fine-tune with the coil slug. If you want a fairly wide BW, then an IF can may be too narrow as-is - but it can be broadened with a little extra loss. Either way, I think it would be superior to using a broadband transformer and cap combo. Ed ___ 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] Mini Circuits RF TX question
I agree with Tim - a common 10.7 MHz IF can is close enough, and will provide a nice tuned circuit that you can rough-in with an extra cap, and also fine-tune with the coil slug. If you want a fairly wide BW, then an IF can may be too narrow as-is - but it can be broadened with a little extra loss. Either way, I think it would be superior to using a broadband transformer and cap combo. Ed ___ 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] Thunderbolt Pattern Failures
Hi, I've had a Trimble Thunderbolt for over three years, and it has functioned flawlessly, even in my high foilage area. During the recent snows, and coldsnap here in the Northeast (New York), my Thunderbolt has dropped signal from all satellites. The antenna is the mushroom one that came with the Chinese kits at that time. Is there a pattern failure for these antennas in sustained temperatures in single digits? One day this week, outdoor temp got over freezing, but all AMUs were still zero. I've searched this list via Gmane, but can't find any discussion on Thunderbolt pattern failures involving loss of rf signals, or antenna reliability. The antenna is well above the snow on the roof, although, I don't dare go up there to check it out until the snow melts. Tboltmon shows no open, and no short for the antenna connection status. Any prognosis on my getting signal back with the first good thaw? Any suggestion on a replacement antenna I can purchase if the antenna is fried? Could an antenna failure cause the rf frontend of the Thunderbolt to also fail? Thanks, Stan ___ 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] Symmetricom 58535A
FS: (1) One, Symmetricom 58535A GPS active 2 port splitter. Excellent condition, from the estate of a SK. $120 plus USPS Small Flate Rate Box (6) to the lower 48. SN: 0637 Thank You Kiss-Electronics Ms Ashley Hall 183 N 5th Avenue Cornelius, Oregon 97113 W7DUZ ashle...@aol.com ___ 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] Thunderbolt Pattern Failures
stan_k...@yahoo.com said: I've had a Trimble Thunderbolt for over three years, and it has functioned flawlessly, even in my high foilage area. During the recent snows, and coldsnap here in the Northeast (New York), my Thunderbolt has dropped signal from all satellites. The antenna is the mushroom one that came with the Chinese kits at that time. ... I had a HP Z3801A do the same thing. After trying another antenna and much screwing around, it recovered when I power cycled it. At least it's simple to try. -- 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] Morion MV89A position
Charles, Thank you for the information and I apologize for responding late. I understand the concept of the sweet spot. I made the changes you mentioned isolate the OCXO thermally from the chasiss. It is out of the Dewar and sitting on a piece Styrofoam. It is then mounted in a chassis that 19 wide 19 deep and 5 or so high. Sure enough after I made the changes the, ADev on time lab shows at 2 sec. all the way up to 3600 sec. With a sample rate of Hz dictated by the 1 PPS out of the thunder bolt the reading are below 2 sec. 1.79 -10, 20 sec 1.95 -11 200 sec 6.83 - 12 1000 sec 1.70 --12 Can you mention the size of the aluminum box you are using to add thermal capacitance? I am very interested to try and improve my results Thank you Paul A. Cianciolo W1VLF http://www.rescueelectronics.com/ Our business computer network is powered exclusively by solar and wind power. Converting Photons to Electrons for over 20 years -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Charles Steinmetz Sent: Friday, January 24, 2014 6:00 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Morion MV89A position Paul wrote: 1) Is the fact that the mv89a is inside a Dewar causing any short term or long term adverse effects? Dewars are appropriate for OCXOs that are designed to work in Dewars. They do not generally improve the temperature regulation of OCXOs that were not designed to work in Dewars, and can significantly compromise the temperature regulation of some OCXOs. An oven works by heating the crystal (and often other circuitry) with a heating element (this is the pull up), which is balanced by heat loss to the ambient environment (this is the pull down). By putting the MV89 in a Dewar, you have reduced the pull down that balances the heater. This means that the heater must stably deliver much less heat than it was designed to, and the heater control circuitry is operating far from its target design point. It may have enough range to work this way, but it is not operating at the design-center sweet spot that the designers chose. This applies to any OCXO, and any form of insulation you use. What you want to achieve is a pull-down rate (rate of heat loss to ambient) similar to the rate anticipated by the thermal designers, but with some integration to slow down the change in cooling rate that occurs when the ambient temperature changes quickly. This gives the heater control servo more time to adjust, thereby improving regulation as the ambient temperature changes. To accomplish this, you want to add thermal capacitance, NOT thermal resistance. The Dewar adds thermal resistance. My solution is to seal the OCXO up in a fairly heavy cast aluminum box (I put the OCXO on teflon or nylon standoffs so there is no direct metal heat-conducting path from the OCXO to the box). You don't really need to do anything more than this for most OCXOs. If you want, you can mount the cast box in another enclosure (again, on thermally-insulating standoffs) with a thermostatically-controlled fan. When I do this, I bond a thermal sensor to the cast aluminum box and use that to drive the fan, so the cast box remains at a constant temperature regardless of changes in the ambient temperature. Best regards, Charles ___ 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] TimeLab and the Adev plot
Whenever I plot an ADEV chart for a given oscillator I see the diagonal line descending from upper left to lower right. With various minor anomalies along the the line. However at near the end of the plot, in this case 3600 sec at 1 sample per sec. the trend begins to reverse at about 1200 sec. in. Is this a function of the shorter term noise being averaged out and some other drift the major contribution to the ADEV? For example at 1200 secs I see 1.72 - 12 and rising to 3.65 -12 at 3600 secs. Does this make sense? Also if there was a description of how to read the ADEV graph that would be great. I have found several resources that describe the math behind this reading but I have yet to really understand it. Thank you Paul A. Cianciolo W1VLF http://www.rescueelectronics.com/ Our business computer network is powered exclusively by solar and wind power. Converting Photons to Electrons for over 20 years ___ 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] TimeLab and the Adev plot
Whenever I plot an ADEV chart for a given oscillator I see the diagonal line descending from upper left to lower right. However at near the end of the plot, in this case 3600 sec at 1 sample per sec. the trend begins to reverse at about 1200 sec. in. Is this a function of the shorter term noise being averaged out and some other drift the major contribution to the ADEV? If you collect enough data, it should be a V shaped graph. On the left side, the error is dominated by measurement noise. Longer times between samples average the noise over a longer time so things look better. On the right side, the error is dominated by the drift in the clock you are measuring. Longer times between samples give the clock more opportunity to drift. There should be several good URLs out there describing that. I don't have one handy. It's pretty obvious after you see it. -- 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] test after email address change and repost of PRS10 question.
Just wanted to say that Gmail has been agonizing lately with their improvements in that sort of stuff. Hats off to John. He keeps the digital home fires lit. Norm n3ykf On Tue, Jan 28, 2014 at 9:30 AM, Chuck Harris cfhar...@erols.com wrote: Time-nuts isn't yahoo. It is something that John Ackermann put together called febo.com. Febo is one of John's cats. Most probably, the OP's email program is set to not display emails which appear to originate from his address... -Chuck Harris Chris Wilson wrote: My recent attempts at posting have been all been blocked for some reason so I am switching email address in the hope that that corrects it. Here is my last one, hoping that it is not a repeat for you guys. Hi, I have just brought my PRS10 out of mothballs and am trying to get a good lock to my TBolt 1PPS. The 1PPS OUT signal from my PRS10 has a very slow rise time, in the order of 70ns. I would be grateful, if anyone here has one on their bench, to let me know what theirs is. I can't find any specification in the literature. Thanks and have a good day. Mike 28/01/2014 11:37 Hi Mike. Both messages (the earlier one from the orange.fr address and this one from the sfr.fr address) are showing. If you read the group using e-mail just CC the messages you post back to yourself and filter into the groups folder. Seems Yahoo changed things (again) recently. ___ 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] TimeLab and the Adev plot
Whenever I plot an ADEV chart for a given oscillator I see the diagonal line descending from upper left to lower right. Does it look like any of these? http://leapsecond.com/museum/manyadev.gif /tvb ___ 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] Morion MV89A position
Paul The MV89 is a double oven unit, and assuming it is setup and working correctly, it's sensitivity to thermo capacity, external temperature effects, sweep spot, and all the other nutty stuff, is Way below the MV89's noise level which is generally under 2e-12 when just setting on a bench in the open. (as long as you do not move or tilt it) All the stuff that is being talked about can effect single oven units. The main purpose of the outer dual oven units, is to isolate the freq change from these effects, and on the several MV89's I tested, it's outer oven works very good and the unit does not need any special mechanical considerations to improve it's stability. Your test data, that shows such high ADEV values is most likely your tester's resolution, assuming you have a clean electrical setup. If your tester does not have at least 1ps (1e-12 seconds) resolution, which few do, then your tester is limiting the ADEV at 1 second. From your data, it looks like your tester is very likely the problem up to at least a couple hundred seconds. In summery, looks like you need a better tester if you want to do any valid performance testing below ~1000 seconds on a typical MV89. ws *** Paul A. Cianciolo paulc at net.net Tue Jan 28 22:53:38 EST 2014 Charles, Thank you for the information and I apologize for responding late. I understand the concept of the sweet spot. I made the changes you mentioned isolate the OCXO thermally from the chasiss. It is out of the Dewar and sitting on a piece Styrofoam. It is then mounted in a chassis that 19 wide 19 deep and 5 or so high. Sure enough after I made the changes the, ADev on time lab shows at 2 sec. all the way up to 3600 sec. With a sample rate of Hz dictated by the 1 PPS out of the thunder bolt the reading are below 2 sec. 1.79 -10, 20 sec 1.95 -11 200 sec 6.83 - 12 1000 sec 1.70 --12 Can you mention the size of the aluminum box you are using to add thermal capacitance? I am very interested to try and improve my results Thank you Paul A. Cianciolo W1VLF ___ 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.
