[time-nuts] Lecia L1 GPS chokering antenna voltage,
I have been trying to find a datasheet for my Leica Antenna. All that is marked on the antenna is part number 10147. I want to find out what voltage range the preamp works off. Anybody have any idea? -marki ___ 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] Lecia L1 GPS chokering antenna voltage,
Check the antenna data on the Leica site http://www.leica-geosystems.com/en/page_catalog.htm?cid=2056. Maybe yours is there. Part Nos don't usually have an easy mapping to product model IDs :-( . If not , I did notice on the ones that I looked at that the supply voltages were all 3,3V-12V. Quite a wide range. Le 15 juil. 2013 à 09:11, Mark C. Stephens a écrit : I have been trying to find a datasheet for my Leica Antenna. All that is marked on the antenna is part number 10147. I want to find out what voltage range the preamp works off. Anybody have any idea? -marki ___ 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] Lecia L1 GPS chokering antenna voltage,
Hi, Is the antenna identical to this? http://www.aeroantenna.com/PDF/AT575-90_G.pdf http://ebookbrowse.com/at575-90-g-pdf-d359926216 (alternate link) Do you have some pictures of the antenna? In particular the antenna element? Aeroantennas of this vintage is usually RG which according to the spec above 5-18VDC. I recall having seen 4.5V as lower level to. Modern antennas are usually good to 3.3 or lower. With vintage antennas this is much more uncertain. -- Björn I have been trying to find a datasheet for my Leica Antenna. All that is marked on the antenna is part number 10147. I want to find out what voltage range the preamp works off. Anybody have any idea? -marki ___ 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] Lecia L1 GPS chokering antenna voltage,
Thank you, It is a AT575-90_G! Now, On the bottom, there is an arrow labelled N. I presume that is supposed to face north? I can't tell you how ideal this antenna is for my application, outstanding! Thank you again. -marki -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of b...@lysator.liu.se Sent: Monday, 15 July 2013 7:02 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Lecia L1 GPS chokering antenna voltage, Hi, Is the antenna identical to this? http://www.aeroantenna.com/PDF/AT575-90_G.pdf http://ebookbrowse.com/at575-90-g-pdf-d359926216 (alternate link) Do you have some pictures of the antenna? In particular the antenna element? Aeroantennas of this vintage is usually RG which according to the spec above 5-18VDC. I recall having seen 4.5V as lower level to. Modern antennas are usually good to 3.3 or lower. With vintage antennas this is much more uncertain. -- Björn I have been trying to find a datasheet for my Leica Antenna. All that is marked on the antenna is part number 10147. I want to find out what voltage range the preamp works off. Anybody have any idea? -marki ___ 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] GPSDO - Does it work?
It is normal for a counter to have a +/- 1 count of wander. Then you have to consider the reference for that counter. When you connect a GPSDO on the input of a counter with its internal reference used as a timing source, you are measuring that internal reference accuracy and stability, not the GPSDO's one. To verify a new GPSDO it is necessary to have another (know good) GPSDO or a Cs reference. Missing that, you can use the PPS output of the GPS receiver but then an average process is needed: say, a digital 'scope with the display persistence function and... wait a lot of time (or use a high resolution TI counter and the TimeLab software). On Mon, Jul 15, 2013 at 4:38 AM, Bob Stewart b...@evoria.net wrote: OK, I finally decided to plug my new GPSDO into my 5334B and give it a try. I made mine with 2 outputs: 10MHz and 5MHz. So, I did the obvious, and perhaps naively expected to see a steady 5.000 on the 5334B. Instead, it bounces back and forth between 4.999 and 5.000. Ummm? Yeah, it's way more accurate than anything I can imagine needing, but it looks like I still have two clocks? Bob - AE6RV ___ 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] WWVB odd propagation 07/14/2013
Hi Paul a major geomag storm occured around midnight UTC on the 14/15th. This precipitated hot electrons into the D-region which causes extra attenuation at night and enhanced daytime long distance signals. The daytime effect is usually short lived but the night-time absorbtion may continue for a few nights, as the ionoshere exchanges charge with the Ring Current (Van Allen belts) Alan G3NYK - Original Message - From: paul swed paulsw...@gmail.com To: paul swed paulsw...@gmail.com; Time-nuts time-nuts@febo.com Sent: Monday, July 15, 2013 2:56 AM Subject: [time-nuts] WWVB odd propagation 07/14/2013 Well this is pretty strange. Working on the WWVB d-psk-r and testing a new simple receiver with agc. Classic transistor design simple, cheap, and common parts. Normal wwvb signal strength on near boston using a Dymec WWVB rcvr quite accurate. daynight 60-80 300-500 today 150150 Fairly constant and we have gone through diurnal shift across the country now. Thats very strange Also verified using a HP3586 and its readings have matched the Dymecs throughout the day. The agc is not getting much of a work out. But I have to say I have never seen wwvbs signal this stable and I am talking many years. Regards Paul WB8TSL ___ 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] Spectrum Analyzer Suggestions
ARRL did a review of a brand new Rigol spectrum analyzer. (Don't remember the model # off hand). But for about $1500,you get an analyzer about the size of the small modern scopes, with warranty. The review wasn't bad, but the unit had a few minor quirks. Depending on your application it may work out well. I'm personally not a fan of the inexpensive Asian stuff, but the price ranges are getting low enough I admit that I'm looking more seriously now. On 7/13/2013 11:49 PM, time-nuts-requ...@febo.com wrote: What I?d appreciate advice for a used spec analyzer in the $1,000 range that is at least much lighter.? A smaller size would also be a benefit. ?I probably would never use it above 100 MHz. A slightly smaller screen would be OK. ___ 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] Spectrum Analyzer Suggestions
Rigol, unlike most of the Asian based manufacturers, does have a support office in the States. They have also had a noticeable presence at the Dayton Hamvention. I'm rather pleased with the low-end Rigol scope I bought at Dayton two years ago. Bob LaJeunesse From: Dan Kemppainen d...@irtelemetrics.com I'm personally not a fan of the inexpensive Asian stuff, but the price ranges are getting low enough I admit that I'm looking more seriously now. ___ 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] Odd propagation
Interesting so others are seeing this behavior also. Its the end of the world. On Mon, Jul 15, 2013 at 1:00 AM, lstosk...@cox.net wrote: The LF guys really noticed this this weekend. Good reason for us to have a band there. N0UU ___ 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] Odd propagation
Not quite LF but 160M (technically MF) was truly spectacularly good in IARU HF from NA to EU and SA. I had a blast and I think the previous NA records for 160M mults were easily shattered. 160M has been pretty good to SA for past couple weeks. Where do the LF guys hang out? Tim N3QE On Mon, Jul 15, 2013 at 1:00 AM, lstosk...@cox.net wrote: The LF guys really noticed this this weekend. Good reason for us to have a band there. N0UU ___ 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] Spectrum Analyzer Suggestions
If you are OK with a 50lb compact box, the HP 8924C Service Monitor can be found with a mechanical input attenuator option that gives you a high performance SA+TG from 400khz-1Ghz plus RF SigGen plus RF Power Meter plus plus plus. If you don't get the right attenuator then its only linear from 10Mhz-1Ghz. In essence it's identical to the famous HP8920A/B just about 25lbs heavier. Nice working examples can be had for less than $1000 . Jerry K1JOS -Original Message- From: Dan Kemppainen [mailto:d...@irtelemetrics.com] Sent: Monday, July 15, 2013 08:58 To: time-nuts@febo.com Subject: [time-nuts] Spectrum Analyzer Suggestions ARRL did a review of a brand new Rigol spectrum analyzer. (Don't remember the model # off hand). But for about $1500,you get an analyzer about the size of the small modern scopes, with warranty. The review wasn't bad, but the unit had a few minor quirks. Depending on your application it may work out well. I'm personally not a fan of the inexpensive Asian stuff, but the price ranges are getting low enough I admit that I'm looking more seriously now. On 7/13/2013 11:49 PM, time-nuts-requ...@febo.com wrote: What I?d appreciate advice for a used spec analyzer in the $1,000 range that is at least much lighter.? A smaller size would also be a benefit. ?I probably would never use it above 100 MHz. A slightly smaller screen would be OK. ___ 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] Spectrum Analyzer Suggestions
On 15 July 2013 14:19, Robert LaJeunesse rlajeune...@sbcglobal.net wrote: Rigol, unlike most of the Asian based manufacturers, does have a support office in the States. They have also had a noticeable presence at the Dayton Hamvention. I'm rather pleased with the low-end Rigol scope I bought at Dayton two years ago. Bob LaJeunesse I don't know if it is true, but I read somewhere that some of the low-end Agilent scopes are made by Rigol. Personally I'd try to work around the weight issues of the HP. At least the HP will be fixable, whereas the Rigol will most likely be unrepairable in a few years time. Dave ___ 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] Odd propagation
I think 136 Khz and 73 Khz and there may a band or 2 higher. On Mon, Jul 15, 2013 at 9:45 AM, Tim Shoppa tsho...@gmail.com wrote: Not quite LF but 160M (technically MF) was truly spectacularly good in IARU HF from NA to EU and SA. I had a blast and I think the previous NA records for 160M mults were easily shattered. 160M has been pretty good to SA for past couple weeks. Where do the LF guys hang out? Tim N3QE On Mon, Jul 15, 2013 at 1:00 AM, lstosk...@cox.net wrote: The LF guys really noticed this this weekend. Good reason for us to have a band there. N0UU ___ 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] GPSDO - Does it work?
On Mon, Jul 15, 2013 at 3:51 AM, time-nuts-requ...@febo.com wrote: So, I did the obvious, and perhaps naively expected to see a steady 5.000 on the 5334B.? Instead, it bounces back and forth between 4.999 and 5.000. You'll need a standard to determine the truth. My recently tweaked 5335A (w/ OCXO) is +- 2 in the LSD when counting my various 10MHz sources. What I'd do: 1) make/buy another and pick one at not quite random to be right. 2) shorten the gate time (round off the count) until happy. In my case my two GPSDOs agree to the resolution of the 5335 so I believe them and and assume I need to adjust my Rb. Of course since I'm just fooling around a few nanoseconds* don't matter so much. *A nanosecond here a nanosecond there, pretty soon you're talking real time. ___ 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] WWVB odd propagation 07/14/2013
Thanks Alan for the clue. I had not seen this behavior before. Now if it would behave like this all the time I would not need AGC. I can only hope. :-) Or my AGC is so good its controlling the entire LF spectrum. Regards WB8TSL On Mon, Jul 15, 2013 at 7:42 AM, Alan Melia alan.me...@btinternet.comwrote: Hi Paul a major geomag storm occured around midnight UTC on the 14/15th. This precipitated hot electrons into the D-region which causes extra attenuation at night and enhanced daytime long distance signals. The daytime effect is usually short lived but the night-time absorbtion may continue for a few nights, as the ionoshere exchanges charge with the Ring Current (Van Allen belts) Alan G3NYK - Original Message - From: paul swed paulsw...@gmail.com To: paul swed paulsw...@gmail.com; Time-nuts time-nuts@febo.com Sent: Monday, July 15, 2013 2:56 AM Subject: [time-nuts] WWVB odd propagation 07/14/2013 Well this is pretty strange. Working on the WWVB d-psk-r and testing a new simple receiver with agc. Classic transistor design simple, cheap, and common parts. Normal wwvb signal strength on near boston using a Dymec WWVB rcvr quite accurate. daynight 60-80 300-500 today 150150 Fairly constant and we have gone through diurnal shift across the country now. Thats very strange Also verified using a HP3586 and its readings have matched the Dymecs throughout the day. The agc is not getting much of a work out. But I have to say I have never seen wwvbs signal this stable and I am talking many years. Regards Paul WB8TSL __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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-nutshttps://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] GPSDO - Does it work?
In this case, I was using the 10MHz output from the GPSDO as the reference and measuring the 5MHz output from the GPSDO. So, even if the GPSDO is off in frequency, the relationship between the 10MHz reference and the 5MHz signal are mathematically fixed. It just seemed strange to me that under such a circumstance the final count would wander only in the minus direction. I expected either to see a solid 5.000, or to see it wandering between 4.999 and 5.001. Bob From: Azelio Boriani azelio.bori...@screen.it To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 4:47 AM Subject: Re: [time-nuts] GPSDO - Does it work? It is normal for a counter to have a +/- 1 count of wander. Then you have to consider the reference for that counter. When you connect a GPSDO on the input of a counter with its internal reference used as a timing source, you are measuring that internal reference accuracy and stability, not the GPSDO's one. To verify a new GPSDO it is necessary to have another (know good) GPSDO or a Cs reference. Missing that, you can use the PPS output of the GPS receiver but then an average process is needed: say, a digital 'scope with the display persistence function and... wait a lot of time (or use a high resolution TI counter and the TimeLab software). ___ 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] GPSDO - Does it work?
Just 1 count: either you see -1, 0 or 0, +1. From -1 to +1 there are 2 counts and, unless the clock is affected by a really bad jitter, it is hard to see more than 1 count of wander in a setup like you did. Anyway, you need a trusted reference, feeding the counter with a 10MHz and counting the same 10MHz divided by 2, doesn't tell you anything. On Mon, Jul 15, 2013 at 5:09 PM, Bob Stewart b...@evoria.net wrote: In this case, I was using the 10MHz output from the GPSDO as the reference and measuring the 5MHz output from the GPSDO. So, even if the GPSDO is off in frequency, the relationship between the 10MHz reference and the 5MHz signal are mathematically fixed. It just seemed strange to me that under such a circumstance the final count would wander only in the minus direction. I expected either to see a solid 5.000, or to see it wandering between 4.999 and 5.001. Bob From: Azelio Boriani azelio.bori...@screen.it To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 4:47 AM Subject: Re: [time-nuts] GPSDO - Does it work? It is normal for a counter to have a +/- 1 count of wander. Then you have to consider the reference for that counter. When you connect a GPSDO on the input of a counter with its internal reference used as a timing source, you are measuring that internal reference accuracy and stability, not the GPSDO's one. To verify a new GPSDO it is necessary to have another (know good) GPSDO or a Cs reference. Missing that, you can use the PPS output of the GPS receiver but then an average process is needed: say, a digital 'scope with the display persistence function and... wait a lot of time (or use a high resolution TI counter and the TimeLab software). ___ 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] GPSDO - Does it work?
On 7/15/2013 10:09 AM, Bob Stewart wrote: In this case, I was using the 10MHz output from the GPSDO as the reference and measuring the 5MHz output from the GPSDO. So, even if the GPSDO is off in frequency, the relationship between the 10MHz reference and the 5MHz signal are mathematically fixed. It just seemed strange to me that under such a circumstance the final count would wander only in the minus direction. I expected either to see a solid 5.000, or to see it wandering between 4.999 and 5.001. Bob If it is counting events, that means it never rounds up. So half the time starting with a 4 and half the time starting with a 5 means that you are in the window between (5 + delta) and (5 - delta) for a very small delta. If all you ever saw was 5.000... then your little window is somewhere in between 5.000...0 and 5.000...1 Is that really where you want to be? 4.... is your friend. Chris w0ep ___ 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] GPSDO - Does it work?
It's mathematical in both frequency, and in phase (clock and channel input timing). Depending on relative cable lengths I suspect you can get lucky and see it always wander 1 count above 5 MHz instead of 1 count below 5 MHz. But you should not expect it to do both; that would be 2 counts; your counter is better than that. /tvb (iPhone4) On Jul 15, 2013, at 8:09 AM, Bob Stewart b...@evoria.net wrote: In this case, I was using the 10MHz output from the GPSDO as the reference and measuring the 5MHz output from the GPSDO. So, even if the GPSDO is off in frequency, the relationship between the 10MHz reference and the 5MHz signal are mathematically fixed. It just seemed strange to me that under such a circumstance the final count would wander only in the minus direction. I expected either to see a solid 5.000, or to see it wandering between 4.999 and 5.001. Bob From: Azelio Boriani azelio.bori...@screen.it To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 4:47 AM Subject: Re: [time-nuts] GPSDO - Does it work? It is normal for a counter to have a +/- 1 count of wander. Then you have to consider the reference for that counter. When you connect a GPSDO on the input of a counter with its internal reference used as a timing source, you are measuring that internal reference accuracy and stability, not the GPSDO's one. To verify a new GPSDO it is necessary to have another (know good) GPSDO or a Cs reference. Missing that, you can use the PPS output of the GPS receiver but then an average process is needed: say, a digital 'scope with the display persistence function and... wait a lot of time (or use a high resolution TI counter and the TimeLab software). ___ 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] GPSDO - Does it work?
OK, I'll buy that. Thanks! From: Tom Van Baak (lab) t...@leapsecond.com To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 11:02 AM Subject: Re: [time-nuts] GPSDO - Does it work? It's mathematical in both frequency, and in phase (clock and channel input timing). Depending on relative cable lengths I suspect you can get lucky and see it always wander 1 count above 5 MHz instead of 1 count below 5 MHz. But you should not expect it to do both; that would be 2 counts; your counter is better than that. ___ 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] 10811 outer oven controller.
Ok, thanks for clarifying. In general the time constant one chooses must reflect both the intrinsic performance of the OCXO (essentially constant) and the realities of GPSDO mechanical, sky-view, and environmental conditions (possibly variable). Disabling an oven during a run is equivalent to a radical change in environment and not re-tuning the loop parameters will lead to sub-optimal or misleading results when plotted. If you have time, it would be instructive to re-run the experiment. First with double oven enabled and do your best case ws-tuning. Then disable the outer oven and again do a best-case tuning. The phase/freq/adev plots would be revealing, as well as the (major?) difference in optimal tuning values. /tvb (iPhone4) On Jul 14, 2013, at 9:19 PM, WarrenS warrensjmail-...@yahoo.com wrote: Tom My posting and plot was only meant to show the difference in tempcoef between an undisciplined single and dual oven 10811 osc which in this case is clearly = 60 to 1. Your comments bring up a different subject which is who needs it and how good does a controlled GPSDO oscillator need to be when not in holdover. As you know, the purpose of a GPSDO control loop is to make the oscillator's long term stability relatively un-important. The longer the measurement time the less important the stability of the controlled osc is in a GPSDO, and as time increases past the GPSDO control loop time constant, the osc stability matters less and less What you are seeing and saying when analyzing the phase and Freq errors plots, is closed loop performance. The phase and freq plots of the dual oven osc would pretty look the same even if compared with a 'perfect' osc, because the dual osc plots is already near or at the noise floor of that TBolt setup and antenna. One can measure the longer term stability of an oscillator different ways; 1) Hold the EFC voltage constant and measure the change in frequency or phase with time. 2) Measure the scaled EFC change necessary to hold the oscillator's freq or phase output constant When done carefully and with the EFC voltage scaled correctly both ways can give the same answer. Answer1) The way I measured the two tempco's is by measuring the correlation between the EFC control voltage and the temperature plot In the case of the single oven osc, the plot gains are set so that when overlayed the EFC DAC plot looks as close as possible to the temperature plot. When the plot time is 24 hr and there is good repeatability, the TC is just the ratio of the two plot gains, i.e theEffective EFC freq change divided by the delta temp. In the single oven case DAC plot gain = 1e-10 per division, temp plot gain = 1.5C per division. Tempco = 1e-10 / 1.5 == 6.7 e-11 / degC. I did the same thing for the dual oven trace by expanding the gain and zero ___ 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] Spectrum Analyzer Suggestions
On Mon, Jul 15, 2013 at 7:37 AM, David Kirkby david.kir...@onetel.netwrote: On 15 July 2013 14:19, Robert LaJeunesse rlajeune...@sbcglobal.net wrote: Rigol, unlike most of the Asian based manufacturers, does have a support office in the States. They have also had a noticeable presence at the Dayton Hamvention. I'm rather pleased with the low-end Rigol scope I bought at Dayton two years ago. Bob LaJeunesse I don't know if it is true, but I read somewhere that some of the low-end Agilent scopes are made by Rigol. Personally I'd try to work around the weight issues of the HP. At least the HP will be fixable, whereas the Rigol will most likely be unrepairable in a few years time. That was true, but I'm not sure it's true any more. The new Rigol 2000 series scopes look very nice, but I just paid Tektronix to tell me my 15 year old TDS210 is still in calibration, so no new scope for me. Back to spectrum analyzers. The Rigol is very nice, but as far as I can tell, an HP 8568A/B is going to beat it handily in terms of phase noise and resolution bandwidth and you can pick up a good example of the HP for about the same price. But you do have the weight issue. You need a GPIB controller if you want to capture screenshots etc. from the HP, but the Prologix USB controller at $150 will do that nicely. If you want new and a warranty, I think the Rigol is the way to go. There is also the Signalhound, but it has software issues and needs a PC to drive it. I got a broken 8568B with the intent of fixing it, selling it and getting a Signalhound. The 8568B, though marginal on its log fidelity test (an in-spec Rigol would be no better) is staying. If you want to know what's in a Rigol SA, Dave Jones has a teardown here: http://www.youtube.com/watch?v=EY0acWrCYjw Orin. ___ 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] 10811 outer oven controller.
The Tbolt LadyHeather plots in my posting are being used as a poor mans high resolution TIC tester as discussed at length in other postings, not for it's GPSDO output capability. This is a method that allows a time-nut person that does not have any of the high end equipment still the ability to do a lot of the high end state of the art time-nut testing. So in this case, it is valid to compare the results of the EFC changes with different types of ovens or even different oscillators such as for finding an oscillators tempco and ageing, as long as the plots are interpreted correctly, because the GPSDO tuning settings have very little if any effect on the long term EFC voltage plots. I have found that one of the largest variables in a GPSDO is the effect that temperature change has on the performance of the OCXO being disciplined. This makes the stability of the OXCO very much a non-constant, in fact temperature effect on the OXCO is the largest variable in many setups. That is why to achieve the best GPSDO performance, or even consistent performance between different runs when using a typical single oven GPSDO, one needs to build a brick house in the basement or put the OXCO under test in a temperature controlled environment such as a dual oven or LH temperature controlled S/W loop. All secondary temperature control devices have the same general goal which is to minimize or eliminate any fast temperature changes and therefore allow the GPSDO to take full advantages of the OCXO's then essentially constant intrinsic performance. Before doing any meaningful comparisons between single and dual oven GPSDOs or comparing the difference in optimal tuning settings, one must first define what the temperature environment is. If the temperature is not allowed to change then there is no difference. With a good dual oven set up, temperature change will have little or no effect, whereas with most time-nut available single oven oscillators including the single oven 10811, temperature variation is the first thing one needs to be consider before tuning for optimal performance. ws ** from Tom Van Baak (lab) tvb at leapsecond.com Mon Jul 15 12:22:38 EDT 2013 Ok, thanks for clarifying. In general the time constant one chooses must reflect both the intrinsic performance of the OCXO (essentially constant) and the realities of GPSDO mechanical, sky-view, and environmental conditions (possibly variable). Disabling an oven during a run is equivalent to a radical change in environment and not re-tuning the loop parameters will lead to sub-optimal or misleading results when plotted. If you have time, it would be instructive to re-run the experiment. First with double oven enabled and do your best case ws-tuning. Then disable the outer oven and again do a best-case tuning. The phase/freq/adev plots would be revealing, as well as the (major?) difference in optimal tuning values. /tvb (iPhone4) ** From: WarrenS Tom My posting and plot was only meant to show the difference in tempco between an undisciplined single and dual oven 10811 osc which in this case is clearly = 60 to 1. Your comments bring up a different subject which is who needs it and how good does a controlled GPSDO oscillator need to be when not in holdover. As you know, the purpose of a GPSDO control loop is to make the oscillator's long term stability relatively un-important. The longer the measurement time the less important the stability of the controlled osc is in a GPSDO, and as time increases past the GPSDO control loop time constant, the osc stability matters less and less What you are seeing and saying when analyzing the phase and Freq errors plots, is closed loop performance. The phase and freq plots of the dual oven osc would pretty look the same even if compared with a 'perfect' osc, because the dual osc plots is already near or at the noise floor of that TBolt setup and antenna. One can measure the longer term stability of an oscillator different ways; 1) Hold the EFC voltage constant and measure the change in frequency or phase with time. 2) Measure the scaled EFC change necessary to hold the oscillator's freq or phase output constant When done carefully and with the EFC voltage scaled correctly both ways can give the same answer. Answer1) The way I measured the two tempco's is by measuring the correlation between the EFC control voltage and the temperature plot In the case of the single oven osc, the plot gains are set so that when overlaid the EFC DAC plot looks as close as possible to the temperature plot. When the plot time is 24 hr and there is good repeatability, the TC is just the ratio of the two plot gains, i.e the effective EFC freq change divided by the delta temp. In the single oven case DAC plot gain = 1e-10 per division, temp plot gain = 1.5C per division. Tempco = 1e-10 / 1.5 == 6.7 e-11 / degC. I did the same thing for the dual
Re: [time-nuts] Spectrum Analyzer Suggestions
On 07/15/2013 10:37 AM, David Kirkby wrote: I don't know if it is true, but I read somewhere that some of the low-end Agilent scopes are made by Rigol. Personally I'd try to work around the weight issues of the HP. At least the HP will be fixable, whereas the Rigol will most likely be unrepairable in a few years time. True, but at about $300 (and declining with time), who'd want to bother with anything other than superficial repairs - replace a BNC jack or clean a button or something? If it quits, just chunk it in the trash and get another. That goes against every molecule of my frugal sensibilities but that's the name of the game in electronics these days. Another consideration is, if a power surge takes out the unit, you don't have a heart attack like one would with a $20k HP or Tek instrument. John -- John DeArmond Tellico Plains, Occupied TN http://www.fluxeon.com -- THE source for induction heaters http://www.neon-john.com-- email from here http://www.johndearmond.com -- Best damned Blog on the net PGP key: wwwkeys.pgp.net: BCB68D77 ___ 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] 10811 outer oven controller.
Hi Warren, I'm a little late to the party, because I just got my GPSDO working. My OCXO (34310-T) is swinging up to 5 or so counts in a 16 second sample and a much bigger swing over 24 hours as reflected in the DAC recording. Do you see any improvement available from passive methods, such as building a foam blanket around the OCXO? Yeah, I could just swap in a better OCXO, but I usually take the less traditional path. =) Bob - AE6RV From: WarrenS warrensjmail-...@yahoo.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 2:16 PM Subject: Re: [time-nuts] 10811 outer oven controller. The Tbolt LadyHeather plots in my posting are being used as a poor mans high resolution TIC tester as discussed at length in other postings, not for it's GPSDO output capability. ___ 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] GPSDO - Does it work?
Slow the Gate time down. -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Paul Sent: Monday, 15 July 2013 11:27 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] GPSDO - Does it work? On Mon, Jul 15, 2013 at 3:51 AM, time-nuts-requ...@febo.com wrote: So, I did the obvious, and perhaps naively expected to see a steady 5.000 on the 5334B.? Instead, it bounces back and forth between 4.999 and 5.000. You'll need a standard to determine the truth. My recently tweaked 5335A (w/ OCXO) is +- 2 in the LSD when counting my various 10MHz sources. What I'd do: 1) make/buy another and pick one at not quite random to be right. 2) shorten the gate time (round off the count) until happy. In my case my two GPSDOs agree to the resolution of the 5335 so I believe them and and assume I need to adjust my Rb. Of course since I'm just fooling around a few nanoseconds* don't matter so much. *A nanosecond here a nanosecond there, pretty soon you're talking real time. ___ 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] 60Khz filters for the WWVB nuts
See item 281136145727 on eBay. Might be nice for WWVB experimentors! 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] GPSDO - Does it work?
Hi Mark, I just tried a10 second gate, and it's still the same, though the 4.999 happens less often. Could it be related to the fact that this is a TTL signal? If I don't set the 50 ohm Z button it counts double - i.e. 10MHz. bob From: Mark C. Stephens ma...@non-stop.com.au To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 3:06 PM Subject: Re: [time-nuts] GPSDO - Does it work? Slow the Gate time down. ___ 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] Lecia L1 GPS chokering antenna voltage,
Good! N is supposed to go to north, yes! But for this antenna it does not matter... longer story below. This is used when you do phase differential stuff. Which usually means L1/L2 stuff and specifically antenna calibration data for az/el. I cannot find any calibration data. http://www.ngs.noaa.gov/ANTCAL/Antennas.jsp?manu=AeroAntenna http://www.geopp.de/index.php?bereich=5kategorie=34artikel=62 However if you look at the AT antennas at NOAA with a spike radome - I think the base chokering is the same as ours. Just a different antenna element in say the AT2775-43. For that antenna it matters! I think the application for the AT575-90 was code differential dgps (marine DGPS) base stations. This service gives the users 1m:ish accuracy. Phase calibration is clearly 10cm and not needed for basic code DGPS. -- Björn Originalmeddelande Från: Mark C. Stephens ma...@non-stop.com.au Datum: 2013-07-15 12:13 (GMT+01:00) Till: Discussion of precise time and frequency measurement time-nuts@febo.com Rubrik: Re: [time-nuts] Lecia L1 GPS chokering antenna voltage, Thank you, It is a AT575-90_G! Now, On the bottom, there is an arrow labelled N. I presume that is supposed to face north? I can't tell you how ideal this antenna is for my application, outstanding! Thank you again. -marki -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of b...@lysator.liu.se Sent: Monday, 15 July 2013 7:02 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Lecia L1 GPS chokering antenna voltage, Hi, Is the antenna identical to this? http://www.aeroantenna.com/PDF/AT575-90_G.pdf http://ebookbrowse.com/at575-90-g-pdf-d359926216 (alternate link) Do you have some pictures of the antenna? In particular the antenna element? Aeroantennas of this vintage is usually RG which according to the spec above 5-18VDC. I recall having seen 4.5V as lower level to. Modern antennas are usually good to 3.3 or lower. With vintage antennas this is much more uncertain. -- Björn I have been trying to find a datasheet for my Leica Antenna. All that is marked on the antenna is part number 10147. I want to find out what voltage range the preamp works off. Anybody have any idea? -marki ___ 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. ___ 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] GPSDO - Does it work?
Without terminating the cable in 50 ohms, you're getting reflections that the counter sees as additional peaks in time. To see much at all one needs 12 digits of resolution. Brian On 7/15/2013 20:46, Bob Stewart wrote: Hi Mark, I just tried a10 second gate, and it's still the same, though the 4.999 happens less often. Could it be related to the fact that this is a TTL signal? If I don't set the 50 ohm Z button it counts double - i.e. 10MHz. bob From: Mark C. Stephens ma...@non-stop.com.au To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 3:06 PM Subject: Re: [time-nuts] GPSDO - Does it work? Slow the Gate time down. ___ 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: 2012.0.2242 / Virus Database: 3204/5992 - Release Date: 07/15/13 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5992 - Release Date: 07/15/13 ___ 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] GPSDO - Does it work?
Unless your frequency counter has some anti-bobble tricks, you will always see +/-1 bobble in the last digit. Of course with longer gates, this last +/-1 becomes a smaller fraction of total count. I personally do not trust a digital meter or counter that doesn't have bobble. I naturally think it's stuck unless it bobbles. Googling anti bobble turns up a lot of references to something to do with fabric and nothing to do with counters and gates :-). Tim N3QE On Mon, Jul 15, 2013 at 4:46 PM, Bob Stewart b...@evoria.net wrote: Hi Mark, I just tried a10 second gate, and it's still the same, though the 4.999 happens less often. Could it be related to the fact that this is a TTL signal? If I don't set the 50 ohm Z button it counts double - i.e. 10MHz. bob From: Mark C. Stephens ma...@non-stop.com.au To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 15, 2013 3:06 PM Subject: Re: [time-nuts] GPSDO - Does it work? Slow the Gate time down. ___ 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] 10811 outer oven controller.
Is anyone aware of a schematic for the oscillator on the web? I have downloaded the usual 10811 manuals but I've never seen a schematic or description of the pin-outs for the double-oven version. Bob Darby On 7/12/2013 11:38 AM, Azelio Boriani wrote: Is it enough if I have a schematic to send? But first let me find it... On Fri, Jul 12, 2013 at 5:13 PM, Mark C. Stephens ma...@non-stop.com.au wrote: I have a spare 10811 double oven, is there a homebrew outer oven controller floating around? -Marki ___ 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.
[time-nuts] Advice Z3816A jumping to Holdover: 1PPS TI exceeds hold threshold, then Recovery: phase alignment for 3-4 hours.
I have a Z3816A and it periodically jumps into holdover with error message: Holdover: 1PPS TI exceeds hold threshold Then for the next 3-4 hours it gradually adjusts the phase alignment. The error message is Recovery: phase alignment [TI +435.5 us] (when I noticed it had changed, they figure was likely to have been much higher) The TI then gradually decreases, currently it is sitting on: Recovery: phase alignment [TI +129.9 us] I am hoping that I won't have to power cycle the GPSDO to get it locked again. I emailed the seller (Yixun HK) and they are trying to tell me power cycle is only fix. They also claim the cause is due to weather? I explained to Yixun I have a lot of smart clocks here and none have exhibited the same problem ever. This is the 3rd defective Z3816A I have got off Yixun and it is costing me a small fortune to send these back. The first was reporting the 12v Supply was out of tolerance, a quick jump into pForth confirmed the A, B and C 12v supplies were over 12.5v. I ended up sending it back to Yixun. The second I was able to fix myself, apparently someone had changed the OCXO but left the insulating-spacing washers out from the pins of the OCXO. This was causing a short on the EFC. That Z3816A unit and now appears to be running normally except the PU is terrible, I'll run Cal for 24 hours and see if it improves. However, Now the 3rd unit is getting this TI exceeded error. I think I have had enough of shipping things back to these guys - they won't replace anything, including parts, unless you ship back to them first. I would just like to get some informed opinions, could the issue be with: a) Antenna b) GPS Module c) OCXO d) PLL circuit on main board. Many thanks, --marki ___ 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] GPSDO - Does it work?
On Mon, Jul 15, 2013 at 8:09 AM, Bob Stewart b...@evoria.net wrote: I expected either to see a solid 5.000, or to see it wandering between 4.999 and 5.001. You'd expect only a one count ambiguity but you question is why 4. and not 5.1? I'm betting it is because of the fixed phase of the 5MHz signal relative to the gate timing. If the counter is counting the number of positive transitions inside a gate time, it might less the last one but would never see an extra. -- Chris Albertson Redondo Beach, California ___ 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] 10811 outer oven controller.
Hi, the recent discussion about 10811's with double oven's caused me to take another look at some of the data I've collected from one of my two GPSDO's that uses a 10811 double oven OCXO. I realize there is much more to the performance of a GPSDO than the OCXO but I can't say I'm unhappy with the performance of this GPSDO and have no complaints about the performance of the OCXO in this application. I expect the data at tau 40 seconds is skewed by the noise of the HP5370B. Sorry that data table for these plots shows the data that is more relevant at longer Tau's (it doesn't show the values for the comparison between the BVA and the Z3805) but the plots show the results at shorter Tau's. As a side note, running standalone none of the 8 or so single oven 10811's I own have ever been able to consistently deliver ADEV or MADEV plots in the 13's at tau's that I am able to measure (ie 40 seconds.) Regards Mark S https://www.dropbox.com/s/jmpnuos0ei324s4/Composite%20MADEV.png?m https://www.dropbox.com/s/3wm2wb6uj9jei7a/Composite%2520ADEV%5B2%5D.png?m -- Message: 6 Date: Mon, 15 Jul 2013 12:16:22 -0700 From: WarrenS warrensjmail-...@yahoo.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] 10811 outer oven controller. Message-ID: 8FAFF758C2AB473EBFAC769FA195DB36@Warcon28Gz Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=response The Tbolt LadyHeather plots in my posting are being used as a poor mans high resolution TIC tester as discussed at length in other postings, not for it's GPSDO output capability. This is a method that allows a time-nut person that does not have any of the high end equipment still the ability to do a lot of the high end state of the art time-nut testing. So in this case, it is valid to compare the results of the EFC changes with different types of ovens or even different oscillators such as for finding an oscillators tempco and ageing, as long as the plots are interpreted correctly, because the GPSDO tuning settings have very little if any effect on the long term EFC voltage plots. I have found that one of the largest variables in a GPSDO is the effect that temperature change has on the performance of the OCXO being disciplined. This makes the stability of the OXCO very much a non-constant, in fact temperature effect on the OXCO is the largest variable in many setups. That is why to achieve the best GPSDO performance, or even consistent performance between different runs when using a typical single oven GPSDO, one needs to build a brick house in the basement or put the OXCO under test in a temperature controlled environment such as a dual oven or LH temperature controlled S/W loop. All secondary temperature control devices have the same general goal which is to minimize or eliminate any fast temperature changes and therefore allow the GPSDO to take full advantages of the OCXO's then essentially constant intrinsic performance. Before doing any meaningful comparisons between single and dual oven GPSDOs or comparing the difference in optimal tuning settings, one must first define what the temperature environment is. If the temperature is not allowed to change then there is no difference. With a good dual oven set up, temperature change will have little or no effect, whereas with most time-nut available single oven oscillators including the single oven 10811, temperature variation is the first thing one needs to be consider before tuning for optimal performance. ws ** from Tom Van Baak (lab) tvb at leapsecond.com Mon Jul 15 12:22:38 EDT 2013 Ok, thanks for clarifying. In general the time constant one chooses must reflect both the intrinsic performance of the OCXO (essentially constant) and the realities of GPSDO mechanical, sky-view, and environmental conditions (possibly variable). Disabling an oven during a run is equivalent to a radical change in environment and not re-tuning the loop parameters will lead to sub-optimal or misleading results when plotted. If you have time, it would be instructive to re-run the experiment. First with double oven enabled and do your best case ws-tuning. Then disable the outer oven and again do a best-case tuning. The phase/freq/adev plots would be revealing, as well as the (major?) difference in optimal tuning values. /tvb (iPhone4) ** From: WarrenS Tom My posting and plot was only meant to show the difference in tempco between an undisciplined single and dual oven 10811 osc which in this case is clearly = 60 to 1. Your comments bring up a different subject which is who needs it and how good does a controlled GPSDO oscillator need to be when not in holdover. As you know, the purpose of a GPSDO control loop is to make the oscillator's long term stability relatively un-important. The longer the measurement
Re: [time-nuts] 10811 outer oven controller.
The schematic has been around for some time. Although it's not the original site (which I believe is now gone), Didier has reposted the info at: http://www.ko4bb.com/Manuals/05%29_GPS_Timing/Z3801/Z3801A_Outer_Oven/Web_Page/Z3801A%20Outer%20Oven%20Controller.htm If necessary, be sure to remove any carriage returns or linefeeds in the URL. Ed On 7/15/2013 7:56 PM, Robert Darby wrote: Is anyone aware of a schematic for the oscillator on the web? I have downloaded the usual 10811 manuals but I've never seen a schematic or description of the pin-outs for the double-oven version. Bob Darby On 7/12/2013 11:38 AM, Azelio Boriani wrote: Is it enough if I have a schematic to send? But first let me find it... On Fri, Jul 12, 2013 at 5:13 PM, Mark C. Stephens ma...@non-stop.com.au wrote: I have a spare 10811 double oven, is there a homebrew outer oven controller floating around? -Marki ___ 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.
