Re: [time-nuts] Distribution amp - Use a video amp unit ?
cfo wrote: On Mon, 26 Mar 2012 08:11:16 +1300, Bruce Griffiths wrote: Bruce Griffiths wrote: A circuit schematic for a current feedback triple with reasonably low noise and distortion is attached. Bruce Thanx Bruce I'm an analog noob , so i have some questions. If i multiply that schematic by 8 , could i then just add the Tbolt input at all V1's ? The input capacitance may be a little high, however one could approximately compensate for it in a narrow band application. Should R15 + C11 + C12 also be multiplied ? One RC decoupling circuit like this for each amplifier is advisable to reduce crosstalk. Is V2 a 12v supply (i suppose so) ? Yes the schematic was taken from an LTSpice simulation. Could i replace the 2N3904 with BC850LT1 (smd) , and the 2N3906 with BC856ALT1 (smd) , else i have some BC337/BC327 - TO92 (non smd) No, the input and output capacitances of those transistors are probably a little too high. Would one chan work on a perf-board with wires (proof of concept) , or would it be to RF sensitive ? Its usually better to construct it over a ground plane rats nest style. A piece of unetched PCB works well. regards CFO Bruce ___ 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] Book by William Riley
On 3/24/2012 3:54 PM, Magnus Danielson wrote: and the Hanbook of Frequency Stability Analysis You didn't mention looking at that one. Any comments about it? ___ 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] Loran-C Anthorn Down Time
To anybody else attempting to use Loran-C from Anthorn in the UK for timing or frequency calibration purposes, I have just found out the hard way that it's scheduled to be off air every day from today until 6th April inclusive between the hours of 0700 and 1900 UTC :-( Other stations in the Lessay chain should still be available during this period. Regards Nigel GM8PZR ___ 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] Distribution amp - Use a video amp unit ?
On 3/25/2012 9:54 PM, gary wrote: MMBD914 !=1n914. 1n914BWTm i.e. using a suffix, is something I haven't seen before, but technically 1N914BWT != 1n914. That is, in the strict sense, the 1n914 has to be a diode in that glass package. As long as we're being pedantic, you're wrong. What you say is only true if it is a JEDEC 1n914 that you're talking about. 1n914 cannot be trademarked or copyrighted. A manufacturer is perfectly free to make a device in a non-glass package and call it a 1n914, which means it _is_ a 1n914, as long as they stay away from JEDEC. Then again, following your lead in being impractically, completely, worthlessly pedantic, it's a JEDEC 1N914, not a 1n914. In the strict sense, the latter cannot exist under JEDEC. No one cares is probably an understatement. ___ 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] Distribution amp - Use a video amp unit ?
Well, *I* care... (Damn, can't even keep a straight face hidden behind email) Ok, well at least it's an amusing argument. Well, partially. So, here's something I've wondered for a while: how are glass cased diodes made? Wouldn't the temperatures needed to form the glass and seal it to the leads destroy the silicon junction being put inside? Peter On 03/26/12, Mike Smi...@flatsurface.com wrote: On 3/25/2012 9:54 PM, gary wrote: MMBD914 !=1n914. 1n914BWTm i.e. using a suffix, is something I haven't seen before, but technically 1N914BWT != 1n914. That is, in the strict sense, the 1n914 has to be a diode in that glass package. As long as we're being pedantic, you're wrong. What you say is only true if it is a JEDEC 1n914 that you're talking about. 1n914 cannot be trademarked or copyrighted. A manufacturer is perfectly free to make a device in a non-glass package and call it a 1n914, which means it _is_ a 1n914, as long as they stay away from JEDEC. Then again, following your lead in being impractically, completely, worthlessly pedantic, it's a JEDEC 1N914, not a 1n914. In the strict sense, the latter cannot exist under JEDEC. No one cares is probably an understatement. ___ time-nuts mailing list -- [1]time-nuts@febo.com To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts@febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ 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] Distribution amp - Use a video amp unit ?
An Si junction can tolerate pretty high temperatures for a short while, or even a long while - Bob Pease reported having had a component sat on the hot end of a soldering iron for about 24 hours and still working afterwards ... I've never seen a description of how they make those glass cased parts - I guess speed is important. Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Peter Gottlieb Sent: 26 March 2012 13:50 To: time-nuts@febo.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? how are glass cased diodes made? Wouldn't the temperatures needed to form the glass and seal it to the leads destroy the silicon junction being put inside? Peter ___ 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] Distribution amp - Use a video amp unit ?
I was only kidding a bit, since for a lot of the most common JEDEC and also non-JEDEC conventional (as opposed to SMD) discrete components they are similar parts with a similar numbering in SMD, and the 1N914 is one of them - so I found it not the best example :) . However, the same argument could be applied to the MMBT3904... in the same sense, != 2N3904 since in the strict sense it is not TO-92. Anyway I was not intending to generate any deep discussion about this matter :) Regards, Javier El 26/03/2012 03:54, gary escribió: MMBD914 !=1n914. 1n914BWTm i.e. using a suffix, is something I haven't seen before, but technically 1N914BWT != 1n914. That is, in the strict sense, the 1n914 has to be a diode in that glass package. On 3/25/2012 5:48 PM, Javier Herrero wrote: El 26/03/2012 02:35, gary escribió: I forgot to mention that those old jedec part numbers specify a package and electrical limit under one part number. That is, you can't find say a 1n914 in SMD, but you can find direct equivalents with other numbers. You will find supply houses listing SMD versions of jedec parts, but technically that is not correct. Oh, you can :) MMBD914 (SOT-23), 1N914BWT /SOD-523F) and some more. Regards, Javier ___ 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] Distribution amp - Use a video amp unit ?
Si juctions are formed at temps of 1000C or more. Thermal failure is more likely to be due to alloying of metal contact areas. I used to lifetest transistors up to 360C for 20 hours with power applied!! and anything up to 6 months at 200C. You cant get those temps with plastic encalsulations though glass (double dummet) diodes will stand 300C easily Alan G3NYK --- On Mon, 26/3/12, David C. Partridge david.partri...@perdrix.co.uk wrote: From: David C. Partridge david.partri...@perdrix.co.uk Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Date: Monday, 26 March, 2012, 14:02 An Si junction can tolerate pretty high temperatures for a short while, or even a long while - Bob Pease reported having had a component sat on the hot end of a soldering iron for about 24 hours and still working afterwards ... I've never seen a description of how they make those glass cased parts - I guess speed is important. Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Peter Gottlieb Sent: 26 March 2012 13:50 To: time-nuts@febo.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? how are glass cased diodes made? Wouldn't the temperatures needed to form the glass and seal it to the leads destroy the silicon junction being put inside? Peter ___ 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] Distribution amp - Use a video amp unit ?
Yes, but The glass used to make the body of the diode melts at something like 1500C! -Chuck Harris ALAN MELIA wrote: Si juctions are formed at temps of 1000C or more. Thermal failure is more likely to be due to alloying of metal contact areas. I used to lifetest transistors up to 360C for 20 hours with power applied!! and anything up to 6 months at 200C. You cant get those temps with plastic encalsulations though glass (double dummet) diodes will stand 300C easily Alan G3NYK ___ 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] Distribution amp - Use a video amp unit ?
On 3/26/2012 10:10 AM, Chuck Harris wrote: The glass used to make the body of the diode melts at something like 1500C! I think they're sintered, not melted, and it's more like 700 C - http://www.us.schott.com/epackaging/english/glass/technical_powder/passivation.html# ___ 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] Distribution amp - Use a video amp unit ?
Bruce wrote: A circuit schematic for a current feedback triple with reasonably low noise and distortion is attached. Quite a good performer for such a simple circuit. I found, both in modeling and on the bench, that there is the usual noise bump at 200-300 MHz and non-monotonic behavior out in the 900 MHz region. The latter can be solved by using an MPSH10 for Q1, which also brings the in-band noise and phase noise down a little. The former can be addressed by adding 8-10 pF across R2, at the expense of lowering the 3 dB point from around 150 MHz to around 80 MHz. For use as a 5 or 10 MHz distribution amp, I'd include the cap. The input impedance stays decently high everywhere the amp has useful gain -- there should be no problem paralleling 10 of them on a 50 ohm source. You can raise R2 just a tad to get back to unity gain, if needed. The reverse isolation is about 35 dB. This can be improved to around 50 dB by adding an emitter follower at the input, adjusting R7 and R8 to maintain Q1's base voltage. The noise increase is negligible. It is fairly sensitive to power supply noise, so you want a nice quiet supply. I used a regulator built with an LM399 and LT1028. Since the transformer is 1:1, one might be tempted to omit it. For a distribution amp that will be connected to a number of different instruments, however, one is well advised to include it to isolate the various returns. 6 bifilar turns on a T43-37 toroid core and 14 bifilar turns on a T61-37 both worked fine for me. If you have 1:1 transformers from a spare Ethernet card, those should, too. For a QD distribution amp, this would be a pretty good candidate. 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.
Re: [time-nuts] Distribution amp - Use a video amp unit ?
Sintered means that the envelope is formed while the glass is in a powdered form, and is then melted to fuse it into glass. The key is they are using a very low temperature glass. For the Dumet seals on the wires (the pink band) to work, the copper in the seal has to be thoroughly wetted by the glass, which means it has to be at the glass melting temperature... and the part has to be cooled slowly to prevent it from shattering... which means it stays hot for a pretty long time. Interesting that the pre ROHS diodes were in a lead glass that could contain as much as 50% lead. The temperatures were higher than the current zinc glass formulations. -Chuck Harris Mike S wrote: On 3/26/2012 10:10 AM, Chuck Harris wrote: The glass used to make the body of the diode melts at something like 1500C! I think they're sintered, not melted, and it's more like 700 C - http://www.us.schott.com/epackaging/english/glass/technical_powder/passivation.html# ___ 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] Distribution amp - Use a video amp unit ?
It would be interesting if the FTS-1050A curves were also plotted. Joe From: John Ackermann N8UR j...@febo.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Date: 03/25/2012 03:54 PM Subject:Re: [time-nuts] Distribution amp - Use a video amp unit ? Sent by:time-nuts-boun...@febo.com I haven't measured the video amps, but here are plots of an HP 5087A, TADD-1, and Spectracom 8140 tap unit for a baseline: http://febo.com/pages/amplifier_phase_noise/ John Tom Knox said the following on 03/25/2012 03:48 PM: Has anyone measured Phase Noise on any of these distribution amps? By looking at how widely the PN specs vary on the application specific Symmetricom and HP DA's it would be interesting to see how well these video da's perform in comparison. Thomas Knox Date: Sun, 25 Mar 2012 12:28:56 -0700 From: p...@petelancashire.com To: time-nuts@febo.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? Sounds like Paul and I have similar DA's or will soon when a Leitch gets to the front porch next week. Its bandwidth is spec'd at 30 MHz. The only question I have on using DA's is the effect of them being designed to work in a 75 ohm environment. One thing to watch out for is what cards they have in them. -pete On Sun, Mar 25, 2012 at 11:39 AM, paul swedpaulsw...@gmail.com wrote: Well the easy answer. The older 1984 video amps would roll off above 6 MC or so. However as the IC technology took over they easily could do 30 Mhz. I have used Grass valley 8500 series for at least 10-15 years and the work very well. I also have sets of Leitch DAs that are fine. Picked up the whole tray for some silly amount of $ 20 I think. I prefer the simple 8601 DAs but have 8604 delay days and they can all be made into simple DAs with a few jumpers that are on the boards. I have also used a rgb da 6 output for each channel. No issue at all. One comment you would want to insure the amps are ac coupled and clamping turned off since there is no sync signal to establish the clamp level. Regards Paul WB8TSL On Sun, Mar 25, 2012 at 2:14 PM, Bruce Griffithsbruce.griffi...@xtra.co.nz wrote: cfo wrote: I need a distribution amp for my Tbolt , with 6..8+ outputs The TAPR-1 is NA , and the successor status is ???. I need it for distributing 10Mhz ref-clock to Counters (HP,Racal,Phillips), a Rigol Sig-gen maybe Oscilloscopes etc. It's for better than ocxo/hobby use , and not Tnut (ps accuracy). I have seen suggestions for using a video distributiution unit. But in my part of the world (EU) , there isn't a lot on eby. I have seen some RGB amps , and was wondering if i could use those ? Could i use a 1:6 RGB unit for : Tbolt on R , FEI-5680A on G - and ?? on B ? I'm not experienced (yet) in the analog domain. If i go (simple diy) Would this one work (also wo. the trafo's) ? http://www.oz9fw.dk/PDF%**20files/rubidium.pdf http://www.oz9fw.dk/PDF%20files/rubidium.pdf I do have some trafo's on an old 10Mhz 8-chan Hub , that i might be able to salvage if needed. Thanx for any input/hints CFo - T-Nut beginner Denmark. __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. Winding your own transformers isnt particularly difficult if you have suitable (binocular) cores. The discrete amplifier shown has a class AB output stage, lower distortion is possible if a class A output stage is used (requires an extra resistor between the output stage emitters and an additional diode in series with the LED). With a Class A output stage the 39 ohm resistors should be replaced by a a pair of 100 ohm resistors to match the load. Significantly lower distortion is possible if feedback from the output to the input stage is used. If the feedback gain is unity (or less) at dc higher AC gains won't significantly degrade the close in phase noise. A different amplifier topology using the same number of transistors will allow a higher reverse isolation to be achieved. One problem with video distribution units (aside from the relatively high phase noise floor) is the limited output drive available. For some purposes 16-20dBm outputs are desirable. Bruce __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts 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] Distribution amp - Use a video amp unit ?
On 3/26/2012 8:15 AM, Charles P. Steinmetz wrote: Bruce wrote: A circuit schematic for a current feedback triple with reasonably low noise and distortion is attached. Quite a good performer for such a simple circuit. I found, both in modeling and on the bench, that there is the usual noise bump at 200-300 MHz and non-monotonic behavior out in the 900 MHz region. The latter can be solved by using an MPSH10 for Q1, which also brings the in-band noise and phase noise down a little. The former can be addressed by adding 8-10 pF across R2, at the expense of lowering the 3 dB point from around 150 MHz to around 80 MHz. For use as a 5 or 10 MHz distribution amp, I'd include the cap. The input impedance stays decently high everywhere the amp has useful gain -- there should be no problem paralleling 10 of them on a 50 ohm source. You can raise R2 just a tad to get back to unity gain, if needed. The reverse isolation is about 35 dB. This can be improved to around 50 dB by adding an emitter follower at the input, adjusting R7 and R8 to maintain Q1's base voltage. The noise increase is negligible. It is fairly sensitive to power supply noise, so you want a nice quiet supply. I used a regulator built with an LM399 and LT1028. Since the transformer is 1:1, one might be tempted to omit it. For a distribution amp that will be connected to a number of different instruments, however, one is well advised to include it to isolate the various returns. 6 bifilar turns on a T43-37 toroid core and 14 bifilar turns on a T61-37 both worked fine for me. If you have 1:1 transformers from a spare Ethernet card, those should, too. For a QD distribution amp, this would be a pretty good candidate. 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. if one is distributing 10 Mhz, does it really matter what the circuit does at 300 and 900 Mhz?? 73's, Randy, KI6WAS ___ 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] Lucent GPS Timing Antenna question
On Sun, Mar 25, 2012 at 04:30:44PM -0700, Jerry Mulchin wrote: I do know that it has 40dB of gain. But I don't know what the power supply voltage is suppose to be. I would assume +5VDC. If any has information I would appreciate getting it if possible. My usual friend Google was of no help. Those were designed for telco references, and from memory, have a pretty wide tolerance. Something like 5-28VDC. I know they'll run okay at 5. Usually saw them paired up with those Lucent GPSDO/Rb shelves. --msa ___ 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] Distribution amp - Use a video amp unit ?
I dont think so, pure quartz melts at, I think, 1440C but glasses (like lead-glass) melt at much lower temperatures 500 to 600C. Remember the chemical glass-blowing skill of the technicians. The glass mix has to be formulated to match the expansion rate of the lead seals. A iron alloy with a small expansion coeff. whose name I dont recall was used for the leads. Glasses soften well below melting temperature (I remember sucked in 807 and 6146 tubes that had dissipated a few watts to many) Then the softened glass is rolled onto the lead. If you look carefully at some glass wire-ended diodes you will see a slight waist where this happened. The seal and adhesion is a thin metal/oxide/glass interface. Soldering temps rarely cause trouble but bending the lead wire close to the glass should be avoided. I used an oxy-hydrogen flame micro-welder for making connections for high temp life tests, so the wires got quite hot, but not close to the metal-glass seal. I only had peripheral knowledge of glass technology but most of the technology was developed in the lamp and valve (tube ) industries. I guess there are great references in the web now :-)) Alan G3NYK --- On Mon, 26/3/12, Chuck Harris cfhar...@erols.com wrote: From: Chuck Harris cfhar...@erols.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? To: Discussion of precise time and frequency measurement time-nuts@febo.com Date: Monday, 26 March, 2012, 15:10 Yes, but The glass used to make the body of the diode melts at something like 1500C! -Chuck Harris ALAN MELIA wrote: Si juctions are formed at temps of 1000C or more. Thermal failure is more likely to be due to alloying of metal contact areas. I used to lifetest transistors up to 360C for 20 hours with power applied!! and anything up to 6 months at 200C. You cant get those temps with plastic encalsulations though glass (double dummet) diodes will stand 300C easily Alan G3NYK ___ 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] Distribution amp - Use a video amp unit ?
Pure quartz glass, which is silicon dioxide, softens (bends) at 1665C, and melts at something around 2000C. Softening and melting are not the same thing. At the softening point glass can be bent without breaking, at the melting point (which is quite wide) it flows like a liquid. It has to get above the flow point to be able to adhere to the Dumet seals on the wire. Soda lime glass melts at about 1500C, as I said, but it bends at about 900C. The highly leaded glasses that they used to use to make glass diodes melt at about 700C, and the highly zinced glasses that they currently use melt at about 560C. I have made metal-glass vacuum seals, and they are done at the liquid point of the glass. At that point, the glass flows and sticks to itself, and just about everything. It is the same temperature used to weld two pieces of like glass to each other. At the bending point, however, glass won't stick to other glass. -Chuck Harris ALAN MELIA wrote: I dont think so, pure quartz melts at, I think, 1440C but glasses (like lead-glass) melt at much lower temperatures 500 to 600C. Remember the chemical glass-blowing skill of the technicians. The glass mix has to be formulated to match the expansion rate of the lead seals. A iron alloy with a small expansion coeff. whose name I dont recall was used for the leads. Glasses soften well below melting temperature (I remember sucked in 807 and 6146 tubes that had dissipated a few watts to many) Then the softened glass is rolled onto the lead. If you look carefully at some glass wire-ended diodes you will see a slight waist where this happened. The seal and adhesion is a thin metal/oxide/glass interface. Soldering temps rarely cause trouble but bending the lead wire close to the glass should be avoided. I used an oxy-hydrogen flame micro-welder for making connections for high temp life tests, so the wires got quite hot, but not close to the metal-glass seal. I only had peripheral knowledge of glass technology but most of the technology was developed in the lamp and valve (tube ) industries. I guess there are great references in the web now :-)) Alan G3NYK ___ 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] Distribution amp - Use a video amp unit ?
Randy wrote: if one is distributing 10 Mhz, does it really matter what the circuit does at 300 and 900 Mhz?? That depends on what it is feeding and what noise and other signals are getting to the DA input. Some synthesized 10 MHz sources produce energy well above 10 MHz. I consider nonmonotonic behavior to be a design flaw in general (except where it is specifically desired or you are up against the bleeding edge of technology and it can't be avoided), so I eliminate it at every opportunity as long as the fix doesn't cause worse problems. In this case, the nonmonotonicity is cured by replacing an 8¢ transistor with a 16¢ transistor, and some other small benefits are realized at the same time, so I say it's 8¢ well spent. Nearly a whole dollar extra for a 12-output DA. The noise bump is cured by restricting the 3 dB bandwidth to ~80 MHz, which does not affect the 10 MHz but may help the receiving instrument if it is sensitive to VHF noise (although the magnitude of the bump is not large). I consider these good prophylactic design measures. Practicing them keeps you out of trouble that you might not even know was threatening, whether or not it makes a practical difference WRT a particular design. 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] LORAN C on the air 1400 EST may have been on all day
Regards Paul ___ 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] Distribution amp - Use a video amp unit ?
I have often seen (don't ask me how) silicon diodes getting so hot that they unsolder themselves from the board and fall at the bottom of the equipment enclosure, yet they work fine after the fact even though they don't look so good. I have been tempted to solder them back in in more than one occasion... I have not had it happen with an smd part yet, but its just a matter of time. Didier KO4BB Sent from my BlackBerry Wireless thingy while I do other things... -Original Message- From: ALAN MELIA alan.me...@btinternet.com Sender: time-nuts-boun...@febo.com Date: Mon, 26 Mar 2012 14:27:39 To: Discussion of precise time and frequency measurementtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? Si juctions are formed at temps of 1000C or more. Thermal failure is more likely to be due to alloying of metal contact areas. I used to lifetest transistors up to 360C for 20 hours with power applied!! and anything up to 6 months at 200C. You cant get those temps with plastic encalsulations though glass (double dummet) diodes will stand 300C easily Alan G3NYK --- On Mon, 26/3/12, David C. Partridge david.partri...@perdrix.co.uk wrote: From: David C. Partridge david.partri...@perdrix.co.uk Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Date: Monday, 26 March, 2012, 14:02 An Si junction can tolerate pretty high temperatures for a short while, or even a long while - Bob Pease reported having had a component sat on the hot end of a soldering iron for about 24 hours and still working afterwards ... I've never seen a description of how they make those glass cased parts - I guess speed is important. Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Peter Gottlieb Sent: 26 March 2012 13:50 To: time-nuts@febo.com Subject: Re: [time-nuts] Distribution amp - Use a video amp unit ? how are glass cased diodes made? Wouldn't the temperatures needed to form the glass and seal it to the leads destroy the silicon junction being put inside? Peter ___ 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] LEA-6T Group buy
Moin, I have the numbers together for the group buy of the u-Blox LEA-6T. I can get them for 120CHF if we can get more then 10 together, which isn't too hard i guess. Add another 3-5CHF shipping, depending on where you live (w/o insurance). How to order: 1) Send me a mail in private. NOT to the mailinglist. Tell me your address and how many you want and i tell you how much it will cost. 2) When more then 10 orders are received, i will ask you to send me the money (bank transfer, no paypal) 3) I close the order end of april and order the LEA-6T Yes, the 120CHF are more than i originally thought it would cost. But i think it's better than paying 145EUR. Also the prices i request are in CHF because i have to pay in CHF. This mail has been long overdue, sorry for the waiting. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] LORAN C on the air 1400 EST may have been on all day
Cape may is up as of 1600 EDST 73, Bill, WA2DVU Cape May, NJ ___ 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] LEA-6T Group buy
On Mon, Mar 26, 2012 at 12:50 PM, Attila Kinali att...@kinali.ch wrote: Moin, I have the numbers together for the group buy of the u-Blox LEA-6T. I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? -- 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] LEA-6T Group buy
On Mon, 26 Mar 2012 12:56:06 -0700 Chris Albertson albertson.ch...@gmail.com wrote: On Mon, Mar 26, 2012 at 12:50 PM, Attila Kinali att...@kinali.ch wrote: Moin, I have the numbers together for the group buy of the u-Blox LEA-6T. I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? What do you mean by spec sheet? The datasheet is available on the homepage [1], beside other timing related info. I think everything you need is there. If not, let me know, i'll try to get u-blox to provide that info as well. Attila Kinali [1] http://u-blox.com/en/gps-modules/u-blox-6-timing-module/lea-6t.html -- Why does it take years to find the answers to the questions one should have asked long ago? ___ 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] LEA-6T Group buy
http://www.u-blox.com/images/downloads/Product_Docs/LEA-6_DataSheet_%28GPS.G 6-HW-09004%29.pdf Regards, Bill Riches, WA2DVU Cape May, NJ - I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? -- 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] LEA-6T Group buy
120CHF + the custom duties. Even if in the EU. On Mon, Mar 26, 2012 at 10:08 PM, Bill Riches bill.ric...@verizon.netwrote: http://www.u-blox.com/images/downloads/Product_Docs/LEA-6_DataSheet_%28GPS.G 6-HW-09004%29.pdf Regards, Bill Riches, WA2DVU Cape May, NJ - I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? -- 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. ___ 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] LEA-6T Group buy
El 26/03/2012 22:30, Azelio Boriani escribió: 120CHF + the custom duties. Even if in the EU. Switzerland is not part of EU :) Although it is part of Schengen Area. Regards, Javier ___ 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] Basic question re adev measurements
Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] LEA-6T Group buy
On 26 Mar, 2012, at 12:56 , Chris Albertson wrote: On Mon, Mar 26, 2012 at 12:50 PM, Attila Kinali att...@kinali.ch wrote: Moin, I have the numbers together for the group buy of the u-Blox LEA-6T. I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? Apart from other issues it may potentially provide significantly more accurate time for computer timekeeping via the Time Mark input, depending on the accuracy of measurements on that input. That is, rather than connecting the PPS output to a computer input pin and then trying to timestamp when the interrupts occur, one can instead tie an output pin from the computer to the Time Mark input and poll for timestamps measured by the LEA-6T, say with a programmed sequence like get computer clock timestamp toggle Time Mark pin get computer clock timestamp . . . ask LEA-6T for Time Mark timestamp If done well that may get the time ambiguity at the computer end down from the microsecond level of interrupt latency to the 100 nanoseconds it should take for a PIO write to a hardware register to complete. If the LEA-6T takes Time Mark timestamps with that precision then this may be a significant improvement. Dennis Ferguson ___ 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] Basic question re adev measurements
A frequency offset is allowed but must stay the same for the entire measurement. On Mon, Mar 26, 2012 at 11:07 PM, Mark Spencer mspencer12...@yahoo.cawrote: Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] Basic question re adev measurements
Hi My first guess is that your limiter is (for what ever reason) doing better at say 1 Hz offset than it is at 10 Hz. Second guess would be that the higher offset is closer to a noise source / spur in your lab. Past that, you get into a lot of that depends things. If you are doing cross correlation then you may be better correlated at the lower offset To directly answer the question - no there nothing about a lower offset that by it's self should improve ADEV, provided the effective measurement bandwidth is not changed. If you change the measurement bandwidth then lower bandwidth means less noise. Since a lot of modern gizmos do a post filter on the data, you do see data plots done that way. Simple answer is that it mostly impacts the shortest Tau for normal sources. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark Spencer Sent: Monday, March 26, 2012 5:07 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question re adev measurements Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] LEA-6T Group buy
Sorry, I meant even if the recipient is in the EU. Interesting the proposed use of the LEA-6T time stamping... On Mon, Mar 26, 2012 at 11:10 PM, Dennis Ferguson dennis.c.fergu...@gmail.com wrote: On 26 Mar, 2012, at 12:56 , Chris Albertson wrote: On Mon, Mar 26, 2012 at 12:50 PM, Attila Kinali att...@kinali.ch wrote: Moin, I have the numbers together for the group buy of the u-Blox LEA-6T. I have not been able to locate a spec sheet for there. Do you have a link? Or maybe you could say how these are improved over the M12M? Apart from other issues it may potentially provide significantly more accurate time for computer timekeeping via the Time Mark input, depending on the accuracy of measurements on that input. That is, rather than connecting the PPS output to a computer input pin and then trying to timestamp when the interrupts occur, one can instead tie an output pin from the computer to the Time Mark input and poll for timestamps measured by the LEA-6T, say with a programmed sequence like get computer clock timestamp toggle Time Mark pin get computer clock timestamp . . . ask LEA-6T for Time Mark timestamp If done well that may get the time ambiguity at the computer end down from the microsecond level of interrupt latency to the 100 nanoseconds it should take for a PIO write to a hardware register to complete. If the LEA-6T takes Time Mark timestamps with that precision then this may be a significant improvement. Dennis Ferguson ___ 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] Distribution amp - Use a video amp unit ?
Charles P. Steinmetz wrote: Bruce wrote: A circuit schematic for a current feedback triple with reasonably low noise and distortion is attached. Quite a good performer for such a simple circuit. I found, both in modeling and on the bench, that there is the usual noise bump at 200-300 MHz and non-monotonic behavior out in the 900 MHz region. The latter can be solved by using an MPSH10 for Q1, which also brings the in-band noise and phase noise down a little. The former can be addressed by adding 8-10 pF across R2, at the expense of lowering the 3 dB point from around 150 MHz to around 80 MHz. For use as a 5 or 10 MHz distribution amp, I'd include the cap. The stability of Sziklai pair like configurations (in this case a triple) is enhanced if the input device has a significantly higher ft than the output device(s). Stable operation at unity gain is necessary if a feedback capacitor is used. The input impedance stays decently high everywhere the amp has useful gain -- there should be no problem paralleling 10 of them on a 50 ohm source. You can raise R2 just a tad to get back to unity gain, if needed. The reverse isolation is about 35 dB. This can be improved to around 50 dB by adding an emitter follower at the input, adjusting R7 and R8 to maintain Q1's base voltage. The noise increase is negligible. The above reverse isolation is about 25dB lower than I would expect. The impedance of the power supply rail at the test frequency should be low so using bypass caps with low inductance and esr is desirable. The reverse isolation of an emitter follower is determined by the current gain at the test frequency. Thus with an ft of 300MHz it should be around 30dB at 10MHz. It is fairly sensitive to power supply noise, so you want a nice quiet supply. I used a regulator built with an LM399 and LT1028. An LM329 has similar noise without the dissipation of the internal heater in the LM399. The 10nF cap between the output transistor bases is the primary source of this sensistivity. Since the transformer is 1:1, one might be tempted to omit it. For a distribution amp that will be connected to a number of different instruments, however, one is well advised to include it to isolate the various returns. 6 bifilar turns on a T43-37 toroid core and 14 bifilar turns on a T61-37 both worked fine for me. If you have 1:1 transformers from a spare Ethernet card, those should, too. For a QD distribution amp, this would be a pretty good candidate. Best regards, Charles Bruce ___ 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] Basic question re adev measurements
It's a bit worse than that. The DUT and reference phase difference can't be allowed to exceed 50 ns per trigger interval, in the case where two ~10 MHz signals are being measured. If the frequencies disagree enough to create a phase slope greater than that -- meaning if they are more than 5E-8 * 10E6 = 0.5 Hz apart if you are triggering once per second -- your TI counts will be aliased. You won't be able to unwrap the phase properly if your software isn't aware that the data is coming from a different Nyquist zone, so to speak. I'd expect some odd looking ADEV plots in that case. -- john -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts- boun...@febo.com] On Behalf Of Mark Spencer Sent: Monday, March 26, 2012 2:08 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question re adev measurements Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] Basic question re adev measurements
Thanks that's helpfull. What happened was one of my first measurement devices and the software I was using didn't handle phase wraps properly so I took pains to limit the frequency off set so I could gather data for 40,000 seconds or more without phase wraps. Now I have equipment and software that can handle phase wraps so I haven't paid as much attention to the frequency off set. From a noise floor perspective the newer setup seems to be as good or better than the old one but I suspect there is another source of error that I am missing. After a few runs at lower frequency off sets with the newer equipment the adev numbers seemed to go down but it is likely a co incidence. I'll have to see what other error sources I can find. Something to keep me busy in my non work time. Regards Mark Spencer -- On Mon, 26 Mar, 2012 5:26 PM EDT Bob Camp wrote: Hi My first guess is that your limiter is (for what ever reason) doing better at say 1 Hz offset than it is at 10 Hz. Second guess would be that the higher offset is closer to a noise source / spur in your lab. Past that, you get into a lot of that depends things. If you are doing cross correlation then you may be better correlated at the lower offset To directly answer the question - no there nothing about a lower offset that by it's self should improve ADEV, provided the effective measurement bandwidth is not changed. If you change the measurement bandwidth then lower bandwidth means less noise. Since a lot of modern gizmos do a post filter on the data, you do see data plots done that way. Simple answer is that it mostly impacts the shortest Tau for normal sources. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark Spencer Sent: Monday, March 26, 2012 5:07 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question re adev measurements Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] Basic question re adev measurements
Thanks John, to put this in perspective the data sets for the good readings might have phase wraps every 40,000 seconds or so. The data sets for the bad adev readings might have phase wraps ever 3,000 seconds or so. Typically I would compare two 10 Mhz signals and take one reading per second. I didn't realize the phase difference can't exceed 50 ns vs 100 ns. I have more to learn here (: This is helpfull. Regards Mark Spencer -- On Mon, 26 Mar, 2012 6:00 PM EDT John Miles wrote: It's a bit worse than that. The DUT and reference phase difference can't be allowed to exceed 50 ns per trigger interval, in the case where two ~10 MHz signals are being measured. If the frequencies disagree enough to create a phase slope greater than that -- meaning if they are more than 5E-8 * 10E6 = 0.5 Hz apart if you are triggering once per second -- your TI counts will be aliased. You won't be able to unwrap the phase properly if your software isn't aware that the data is coming from a different Nyquist zone, so to speak. I'd expect some odd looking ADEV plots in that case. -- john -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts- boun...@febo.com] On Behalf Of Mark Spencer Sent: Monday, March 26, 2012 2:08 PM To: time-nuts@febo.com Subject: [time-nuts] Basic question re adev measurements Greetings, I was reviewing some older adev plots of mine and noticed that there may be a correlation between lower adev numbers and lower frequency off set between the reference source and the device under test. It's my understanding that the adev calculations remove constant frequency off sets but I'm wondering in practice this degrades the the measurements. It occurs to me that if I am comparing two 10 MHz signals with a TIC that the available dynamic range of each measurements will be 100 ns. Would a constant frequency off set effectively reduce the precision of the measurements by eating up some of this dynamic range ? To put this in perspective frequency offsets of say one or two parts per trillion seem to result in better adev readings than off sets of say ten or more parts per trillion. Sorry if I have missed something obvious here. Thanks in advance Mark Spencer Sent from my iPod ___ 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] FE5680A x-rays
Ok here they are: About 30 real-time X-ray images were done in transmission and the images were captured using the imaging system, printed and later assembled to create a one meter scale of the printed circuit board. A low voltage, in the 50kV range, was used to better visualise the hidden copper traces. In the attached file the two directories in Data are one: image format in raw (need to be flipped and rotated as needed if you want to look up or down at the pc board) and two: in the psd Photoshop format. They can be converted to jpg with a slight loss of resolution by many software packages, if desired. Two other files, in the top level, are for guidance in positioning them on the chart and a look at the final assembly result (at much lower resolution). The images are available at: http://download.muanalysis.com/FE-5680A.zip EnjoY I am happy as my unit is now working correctly. It was an e-bay bargain if you don't count the debug time!!! Hope this info will be useful to others. ___ 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] FE5680A x-rays
Hi Rich, please advise which program can I open the files...?? Rgds Ernie. -Original Message- From: Rich msima...@sympatico.ca To: time-nuts time-nuts@febo.com Sent: Tue, Mar 27, 2012 12:24 am Subject: Re: [time-nuts] FE5680A x-rays Ok here they are: About 30 real-time X-ray images were done in transmission nd the images were captured using the imaging system, rinted and later assembled to create a one meter scale of he printed circuit board. A low voltage, in the 50kV range, as used to better visualise the hidden copper traces. In the attached file the two directories in Data are ne: image format in raw (need to be flipped nd rotated as needed if you want to look up or down at the pc board) and wo: in the psd Photoshop format. They can be converted to jpg with a slight loss of esolution by many software packages, if esired. Two other files, in the top level, re for guidance in positioning them on the chart and a ook at the final assembly result (at much lower resolution). The images are available at: ttp://download.muanalysis.com/FE-5680A.zip EnjoY am happy as my unit is now working correctly. t was an e-bay bargain if you don't count the debug time!!! ope this info will be useful to others. __ 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] Book by William Riley
The Handbook of Frequency Stability Analysis and the Stable 32 manual are hard copies of the pdfs that you can download free from his web site ( www.wriley.com ). Ed On 3/26/2012 2:34 AM, Rex wrote: On 3/24/2012 3:54 PM, Magnus Danielson wrote: and the Hanbook of Frequency Stability Analysis You didn't mention looking at that one. Any comments about it? ___ 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] FE5680A x-rays
Photoshop works with both the RAW and the PSD format. There are several free programs that will convert them in jpg with some loss of resolution. If the format is a problem to people I'll see if I can convert them to jpg but they won't be as sharp and you will loose some contrast control. The RAW pix look almost all black in Photoshop until you use the autolevel function. ___ 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] FE5680A x-rays
Rich, Would it not be better to make them a TIFF format ? While larger in size, there would be no loss of resolution. BillWB6BNQ Rich wrote: Photoshop works with both the RAW and the PSD format. There are several free programs that will convert them in jpg with some loss of resolution. If the format is a problem to people I'll see if I can convert them to jpg but they won't be as sharp and you will loose some contrast control. The RAW pix look almost all black in Photoshop until you use the autolevel function. ___ 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] New M12+ and M12M compatible GPS module
Hi all, I thought I'd post this since it's related to the same company. Chris Albertson posted this on the NTP Questions list recently in response to one of my queries. quote on -- If you are looking for a brand new timing GPS and don't like buying on eBay, I think the best deal is going to be The M12M because Synergy has offered to sell to people on these email lists at a discounted price of just below $60. If you had to pay list price for a new production timing unit you'd pay 10X that much.I don't mind buying older units on eBay but I can understand if sue one wanted technical support and a warranty and current 2012 state of the art, you don't get any of that on eBay. Here is a link Synergy M12M http://www.synergy-gps.com/index.php?option=com_contenttask=viewid=104Itemid=109 http://www.synergy-gps.com/index.php?option=com_contenttask=viewid=104Itemid=109 You will have to talk directly to them about buying it and ask for the reduced price.I have two of a 15 year old version of this. I looks almost the same. they have the same 10 pin male header except now they use 0.05 inch sping rather then 0.1 -- Chris Albertson Redondo Beach, California -- quote off Sincerely, Ron On 3/25/2012 5:37 PM, Rick Hambly (W2GPS) wrote: For those of you looking for a new design GPS receiver module compatible with the Motorola M12+ and M12M receivers, Synergy has developed the u-blox based SSR-6Tr that is plug compatible with M12x receivers. The SSR-6tr includes Motorola binary protocol as well as u-blox binary and NMEA protocols. This development was announced at the PTTI Conference in Long Beach, CA last year. Technical details, samples and production information will be posted shortly on Synergy's' web site (www.synergy-gps.com). Prices of this better performing, backward compatible SSR-6Tr GPS timing receiver are expected to be as listed for the current Motorola designed M12M timing receiver distributed by Synergy. Synergy's normal 10% educational discount applies to non-commercial educational pursuits including Ham Radio. For features and performance data, see the LEA-6T timing receiver module specifications at www.ublox.com. Size, weight, power consumption and connector locations are similar to M12x receivers to guarantee backward compatibility. Rick W2GPS -- (PS - If you email me and don't get a quick response, don't be concerned. I get about 300 emails per day from alternate energy mailing lists and such. I don't always see new messages very quickly. If you need a reply and have not heard from me in 1 - 2 weeks, send your message again.) Ron Frazier timekeepingdude AT c3energy.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] New M12+ and M12M compatible GPS module
Thanks Ron Thomas Knox Date: Mon, 26 Mar 2012 23:53:15 -0400 From: timekeepingntpl...@c3energy.com To: time-nuts@febo.com Subject: Re: [time-nuts] New M12+ and M12M compatible GPS module Hi all, I thought I'd post this since it's related to the same company. Chris Albertson posted this on the NTP Questions list recently in response to one of my queries. quote on -- If you are looking for a brand new timing GPS and don't like buying on eBay, I think the best deal is going to be The M12M because Synergy has offered to sell to people on these email lists at a discounted price of just below $60. If you had to pay list price for a new production timing unit you'd pay 10X that much.I don't mind buying older units on eBay but I can understand if sue one wanted technical support and a warranty and current 2012 state of the art, you don't get any of that on eBay. Here is a link Synergy M12M http://www.synergy-gps.com/index.php?option=com_contenttask=viewid=104Itemid=109 http://www.synergy-gps.com/index.php?option=com_contenttask=viewid=104Itemid=109 You will have to talk directly to them about buying it and ask for the reduced price.I have two of a 15 year old version of this. I looks almost the same. they have the same 10 pin male header except now they use 0.05 inch sping rather then 0.1 -- Chris Albertson Redondo Beach, California -- quote off Sincerely, Ron On 3/25/2012 5:37 PM, Rick Hambly (W2GPS) wrote: For those of you looking for a new design GPS receiver module compatible with the Motorola M12+ and M12M receivers, Synergy has developed the u-blox based SSR-6Tr that is plug compatible with M12x receivers. The SSR-6tr includes Motorola binary protocol as well as u-blox binary and NMEA protocols. This development was announced at the PTTI Conference in Long Beach, CA last year. Technical details, samples and production information will be posted shortly on Synergy's' web site (www.synergy-gps.com). Prices of this better performing, backward compatible SSR-6Tr GPS timing receiver are expected to be as listed for the current Motorola designed M12M timing receiver distributed by Synergy. Synergy's normal 10% educational discount applies to non-commercial educational pursuits including Ham Radio. For features and performance data, see the LEA-6T timing receiver module specifications at www.ublox.com. Size, weight, power consumption and connector locations are similar to M12x receivers to guarantee backward compatibility. Rick W2GPS -- (PS - If you email me and don't get a quick response, don't be concerned. I get about 300 emails per day from alternate energy mailing lists and such. I don't always see new messages very quickly. If you need a reply and have not heard from me in 1 - 2 weeks, send your message again.) Ron Frazier timekeepingdude AT c3energy.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. ___ 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.
