Re: [time-nuts] Loran C returning to a station near you...
FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1900Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] how to find low noise transistors
noise figure, noise voltage, noise current: http://www.ti.com/lit/an/slyt094/slyt094.pdf On 7/18/2015 2:16 AM, Attila Kinali wrote: On Fri, 17 Jul 2015 23:25:10 -0400 Charles Steinmetz csteinm...@yandex.com wrote: A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Attila Kinali ___ 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] Rohde Schwarz frequency standard and controller
Good morning, I have 3 working XSRM Rubidium RS standards in use, at 60 KHz , the short term stability is better then the more modern ones but the internal battery system does not work (well) . External 24 V charger is better. Ulrich, N1UL In a message dated 7/18/2015 10:25:58 A.M. Eastern Daylight Time, robe...@dcsi.net.au writes: Hello Group, I recently acquired a couple of R S XSD frequency standards and XKE frequency controllers ( circa mid 1960's ) as well as the manuals that go with them. I've had a quick look on the net and haven't found much in the way of documentation so I have scanned the manuals into PDF files. They include schematics, parts lists, operation and fault finding with the XSD manual coming in at 79 Meg and the XKE manual coming in at 41 Meg. I have put them up on Didier's website for access. Cheers Everyone, Rob VK3BRS ___ 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] 5 x 2 x 3 = 30 MHz
The whole USO is about $1M, the vast majority of which is labor. Analysis, testing, paperwork, etc Jim Original message From: Bob Camp kb...@n1k.org Date: 07/18/2015 02:10 (GMT+00:00) To: tim...@timeok.it, Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] 5 x 2 x 3 = 30 MHz Hi The basic space grade crystal is in the $400 to $1000 range (depends on quantity). After they do the 10:1 sort, the resulting ones are (effectively) $4K to $10K each. The cost just goes up from there.If you count in the labor, it probably adds another 30% to the cost. If you don’t do the sorts, the basic crystal is not (on average) much better than any other 5MHz unit with the same blank size. Yield through the whole process is dependent on the batch they get. It *may* be 10%. Bob On Jul 17, 2015, at 5:50 AM, tim...@timeok.it wrote: I an curious to know the price of this crystal. Luciano On Fri 17/07/15 00:02 , KA2WEU--- via time-nuts time-nuts@febo.com wrote: I am working with this .. amazing device, Ulrich N1UL ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts [1] and follow the instructions there. Links: -- [1] http://webmail.timeok.it/parse.php?redirect=https://www.febo.com/cgi-bin/ma ilman/listinfo/time-nuts Message sent via Atmail Open - http://atmail.org/ ___ 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] 5 x 2 x 3 = 30 MHz
Good morning, the AT Cut is inherently noisier then the SC cut but the SC has some spurious resonances modes. Measurements below 1 Hz are very tricky as the oscillator must be (more or less) insulated from hum, infrared (heater) . Here I am still struggling . Ulrich N1UL In a message dated 7/17/2015 9:59:55 P.M. Eastern Daylight Time, n1...@dartmouth.edu writes: He doesn't mention that that crystal is used in New Horizons: http://www.bliley.com/products/crystals-precision-standard/vacuum-sealed/ Nice. I have a similar crystal from Valpey-Fischer, 5 MHz 5th overtone AT-cut (as opposed to your 3rd overtone SC-cut). I would be interested in what you would use for an oscillator circuit. David N1HAC On 7/17/15 4:27 PM, paul swed wrote: Ulrich, Nice picture. What are you doing with the crystal? I have several older crystals that are nice but have never done anything with them. Regards Paul WB8TSL On Thu, Jul 16, 2015 at 6:02 PM, KA2WEU--- via time-nuts time-nuts@febo.com wrote: I am working with this .. amazing device, Ulrich N1UL ___ 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] Firmware and antenna for Stanford Research FS700 Loran C frequency standard
I had a few LM394CN left and used one for the pre-amp. I would try to use another low-noise transistor. Furthermore, you do not necessarily need a matched pair. The transistor on the right in the schematic is merely used for biasing the amplifying transistor on the left. The prices for matched pairs can get ridiculously high, so I too would try to look for alternatives. If you still want a matched pair, there's the SSM2212 from Analog Devices, which is priced lower than the MAT12. You may also be able to find the earlier SSM2210, which now is obsolete. Another alternative is the THAT300 from THAT Corporation, which has 4 low-noise NPNs in a 14-pin DIP (great for experiments...) Useful single NPN transistors I can think of would likely be the BC337 or perhaps the 2SC3324 which both have low Rbb, and they are quite cheap. The Ca. 3 Ohm was indeed the estimated input resistance, including the series resistance of the input capacitor as I recall. Best regards Ole Den 17-07-2015 kl. 22:49 skrev Dr. David Kirkby (Kirkby Microwave Ltd): On 16 July 2015 at 08:05, Ole Stender Nielsen ols...@mail.tele.dk wrote: I use a home-made untuned loop antenna with 4 windings of 2.5 mm2 insulated wire on a 80 x 80 cm wooden frame, and with a grounded base pre-amplifier mounted on the antenna frame. A schematic is enclosed for you to copy. The pre-amplifier is powered through the cable, and loads the FS700 input as required. I live about 290 km from the island of Sylt, and get nice noise margin figures from the FS700, normally about 40 dB, often up to 46 dB. A couple of questions 1) Do you have any suggestions for a replacement for the LM394CN, which is obsolete and unobtainable from any reputable source? There are plenty on eBay for a few $'s from China, but the probability of them being fakes is greater than 0.99. The MAT12 seems to be one possible candidate for a replacement and while not cheap, is available from reputable sources like Farnell. 2) What is the Ca. 3 Ohm to the left of your circuit? Is that what you estimate the input impedance is? I've got 95 m of 2.5 mm^2 wire. The resistance of that is about 7.41 mOhm/m so my 95 m would have a DC resistance of around 7 Ohms if I used it all. I have built the loop 1.0 x 1.2 m. Hopefully that will be ok to receive at least one or both of * Lessay, France, power = 250 kW, distance = 321 km, bearing = 211 degrees. * Anthorn, England, power =- 250 kW, distance = 419 km, bearing 331 degrees. I now need to work out how many turns to put on it. 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. ___ 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] Firmware and antenna for Stanford Research FS700
generally larger transistors running at much lower current than they inteded for have lover noise figure, but much larger input and [Cbe] and feedback Ccb] capacitance, the same effect could be achieved putting --for AC!-- low noise transistors paralell [ signal voltage adds arithmetically, noise voltage adds vectorial -- quadratic like power ] most of the case power transistors are also not so fast lower fT. On 7/18/2015 3:16 AM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote: On 18 July 2015 at 04:25, Charles Steinmetz csteinm...@yandex.com wrote: Dave wrote: 1) Do you have any suggestions for a replacement for the LM394CN, which is obsolete and unobtainable from any reputable source? There are plenty on eBay for a few $'s from China, but the probability of them being fakes is greater than 0.99. The MAT12 seems to be one possible candidate for a replacement and while not cheap, is available from reputable sources like Farnell. The MAT12 should certainly work, but there is *plenty* of DC degeneration in the circuit (1v at each emitter), so there is no advantage to matched transistors. A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. Best regards, Charles Do you really mean the ZTX849? It is a power transistor (5A continuous current collector current, 20 A peak collector current), with no specification for noise on the data sheet. It would on the face of it hardly seem a wise choice for a low noise amplifier, but perhaps you know something I don't. The LM394CN or MAT12 are at least a low-noise devices, even if the matching between the two transistors in the package is not needed. 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. ___ 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] Rohde Schwarz frequency standard and controller
Hello Group, I recently acquired a couple of R S XSD frequency standards and XKE frequency controllers ( circa mid 1960's ) as well as the manuals that go with them. I've had a quick look on the net and haven't found much in the way of documentation so I have scanned the manuals into PDF files. They include schematics, parts lists, operation and fault finding with the XSD manual coming in at 79 Meg and the XKE manual coming in at 41 Meg. I have put them up on Didier's website for access. Cheers Everyone, Rob VK3BRS ___ 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] how to find low noise transistors (was: Firmware and antenna for Stanford Research FS700)
On Fri, 17 Jul 2015 23:25:10 -0400 Charles Steinmetz csteinm...@yandex.com wrote: A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Attila Kinali -- I must not become metastable. Metastability is the mind-killer. Metastability is the little-death that brings total obliteration. I will face my metastability. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the metastability has gone there will be nothing. Only I will remain. ___ 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] Firmware and antenna for Stanford Research FS700
On 18 July 2015 at 04:25, Charles Steinmetz csteinm...@yandex.com wrote: Dave wrote: 1) Do you have any suggestions for a replacement for the LM394CN, which is obsolete and unobtainable from any reputable source? There are plenty on eBay for a few $'s from China, but the probability of them being fakes is greater than 0.99. The MAT12 seems to be one possible candidate for a replacement and while not cheap, is available from reputable sources like Farnell. The MAT12 should certainly work, but there is *plenty* of DC degeneration in the circuit (1v at each emitter), so there is no advantage to matched transistors. A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. Best regards, Charles Do you really mean the ZTX849? It is a power transistor (5A continuous current collector current, 20 A peak collector current), with no specification for noise on the data sheet. It would on the face of it hardly seem a wise choice for a low noise amplifier, but perhaps you know something I don't. The LM394CN or MAT12 are at least a low-noise devices, even if the matching between the two transistors in the package is not needed. 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] how to find low noise transistors (was: Firmware and antenna for Stanford Research FS700)
Hi You have (and always have had) two basic choices: 1) Buy a very expensive part from somebody who has gone to the trouble of characterizing the noise performance and will guarantee at least some of what they show on the data sheet. 2) Buy a bunch of cheap transistors and test them. Lock in on a specific part and vendor. Keep monitoring what you get in case they “improve” their process and the magic goes away. How do you select candidates? That’s never been easy, there is less and less data on the sheets every day. Normally the first step is to look at a vendor that you have had luck with in the past. The next step is to ask them… Bob On Jul 18, 2015, at 5:16 AM, Attila Kinali att...@kinali.ch wrote: On Fri, 17 Jul 2015 23:25:10 -0400 Charles Steinmetz csteinm...@yandex.com wrote: A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Attila Kinali -- I must not become metastable. Metastability is the mind-killer. Metastability is the little-death that brings total obliteration. I will face my metastability. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the metastability has gone there will be nothing. Only I will remain. ___ 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] Firmware and antenna for Stanford Research FS700
Dave wrote: Do you really mean the ZTX849? It is a power transistor (5A continuous current collector current, 20 A peak collector current), with no specification for noise on the data sheet. It would on the face of it hardly seem a wise choice for a low noise amplifier, but perhaps you know something I don't. Yep. They are not marketed (yet) for low noise amplification, but they have about the lowest voltage noise you can get while at the same time not having huge junction capacitances and exhibiting good current gain down to 1mA and below. Innovative process features that were developed to provide very low saturation voltage also produced benefits that were not targeted by the designers -- in this case, very low voltage noise. Attila wrote: I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Noise in BJTs is well correlated with the base spreading resistance, Rbb. But Rbb is almost never given on datasheets, except in the case of a very few transistors marketed specifically as low-noise amplifiers (e.g., the obsolete Rohm 2SB737 and 2SD786). It is well known that Rbb goes down as the die size increases, so large power transistors have sometimes been used as low-noise, small-signal amplifiers. However, the current gain of 20 amp power transistors (TO-3, TO-220) generally falls off severely at the low currents used for small-signal amplifiers, and the large die have very large junction capacitances, which severely limits bandwidth. Zetex makes a series of high-current, low Vsat transistors on much smaller die, using a new process that also maintains high current gain below 10 mA. I've been using the 849s as low-noise amplifiers since last century, and have recommended them a number of times both here and on the volt-nuts list. As those who have read the new 3rd edition of The Art of Electronics know, the authors recommend the 849's cousin, ZTX/FZT851, in this same role. One finds good candidates to measure by applying an understanding of basic solid state physics to what manufacturers *do* say about their products. Or now, by reading the 3rd edition of The Art of Electronics. (Like its predecessors, I consider this an absolutely indispensable book for anyone who dabbles with circuit design, from the newbie nimrod to the crusty old designer who has forgotten more than any newly-minted PhD/EE knows.) I posted a lab note on measuring base spreading resistance to Didier's site long ago: http://www.ko4bb.com/manuals/download.php?file=06_Misc_Test_Equipment/3_Manuals_to_be_sorted/Measuring_base_spreading_resistance.pdf 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] Loran C returning to a station near you...
Correction on times for Mon - thurs - start 900 edst - 1300Z -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Saturday, July 18, 2015 7:05 AM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1300Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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 returning to a station near you...
OK LORAN is on the air up in Boston. I had just turned off various equipment this morning. So starting it back up after testing it yesterday. Lots of large static crashes. Regards Paul WB8TSL On Sat, Jul 18, 2015 at 7:04 AM, billriches bill.ric...@verizon.net wrote: FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1900Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] Loran C returning to a station near you...
What GRI is in use I'll fire up my austron as well Central NH location Content by Scott Typos by Siri On Jul 18, 2015, at 1:42 PM, paul swed paulsw...@gmail.com wrote: Bill I will let you know what the Austrons say for signal level. Fact is they locked up fast. My FS700 is taking its time. Graham it will sound different as there are no competing stations on other GRIs. Thats the very first thing that hits you. Additionally its only 1 station. But that same station is sending the master and secondary delayed emission. Its simply not the same ole sound. But it still works very well for checking frequency. Regards Paul WB8TSL On Sat, Jul 18, 2015 at 12:52 PM, billriches bill.ric...@verizon.net wrote: Correction on times for Mon - thurs - start 900 edst - 1300Z -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Saturday, July 18, 2015 7:05 AM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1300Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] Loran C returning to a station near you...
Hi Paul - how do you figure boston? The only station up is Wildwood, NJ -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of paul swed Sent: Saturday, July 18, 2015 1:15 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Loran C returning to a station near you... OK LORAN is on the air up in Boston. I had just turned off various equipment this morning. So starting it back up after testing it yesterday. Lots of large static crashes. Regards Paul WB8TSL On Sat, Jul 18, 2015 at 7:04 AM, billriches bill.ric...@verizon.net wrote: FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1900Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] how to find low noise transistors
Good afternoon, There is a problem in the literature that people confuse the spot noise figure and the large signal noise properties. Here AF and KF needs to be known and considered. Here is the mathematical correct formula in a Word for Windows Form attached file. If you use it for publications, please quote me . Thanks My advise is take a BIP transistor , fT not much more then 20 x operating frequency (lower flicker component) and operate it at 15 to 20 % of ICmax. The BFG540 is amongst the best Oscillators oscillators http://www.nxp.com/documents/data_sheet/BFG540_X_XR_N.pdf Now you outperform most colleagues 73 de Ulrich N1UL x In a message dated 7/18/2015 1:19:57 P.M. Eastern Daylight Time, p...@petelancashire.com writes: https://scholar.google.com/scholar?q=measuring+transistor+noisehl=enas_sdt =0as_vis=1oi=scholart OscPN.docx Description: Binary data ___ 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] how to find low noise transistors
but be sure that you have a hp4470B --a transistor noise analyzer [ http://www.testequipmenthq.com/datasheets/Agilent-4470B-Datasheet.pdf ] 73 Alex On 7/18/2015 8:47 AM, Pete Lancashire wrote: I agree with Bob, find a vendor you can trust and make sure you buy from an authorized distributor or if just need two or three parts try to get them as samples.directly from the manufacturer. The reason for this is you may get a fake or reject part and you will never know. Trying to do the measurements yourself is pretty much out of the question today.. Every improvement made it harder in that the equipment had to itself be lower in noise If interested https://scholar.google.com/scholar?q=measuring+transistor+noisehl=enas_sdt=0as_vis=1oi=scholart . -pete On Sat, Jul 18, 2015 at 5:29 AM, Bob Camp kb...@n1k.org wrote: Hi You have (and always have had) two basic choices: 1) Buy a very expensive part from somebody who has gone to the trouble of characterizing the noise performance and will guarantee at least some of what they show on the data sheet. 2) Buy a bunch of cheap transistors and test them. Lock in on a specific part and vendor. Keep monitoring what you get in case they “improve” their process and the magic goes away. How do you select candidates? That’s never been easy, there is less and less data on the sheets every day. Normally the first step is to look at a vendor that you have had luck with in the past. The next step is to ask them… Bob On Jul 18, 2015, at 5:16 AM, Attila Kinali att...@kinali.ch wrote: On Fri, 17 Jul 2015 23:25:10 -0400 Charles Steinmetz csteinm...@yandex.com wrote: A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Attila Kinali -- I must not become metastable. Metastability is the mind-killer. Metastability is the little-death that brings total obliteration. I will face my metastability. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the metastability has gone there will be nothing. Only I will remain. ___ 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] how to find low noise transistors
The BFG540 is amongst the best Oscillators oscillators http://www.nxp.com/documents/data_sheet/BFG540_X_XR_N.pdf Now you outperform most colleagues 73 de Ulrich N1UL Last time buy 31-Dec-15. :( Have you heard of any good substitutes? I've built a lot of amps with BFG591s, and they also got the axe recently. Small-signal RF bipolars seem to be an endangered species. -- john, KE5FX Miles Design LLC ___ 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] manual upload
Uploaded to KO4BB: Kode Odetics 3100 time interval analyzer op manual 100 ps min timebase, 10 ps error a boatanchor but IEEE488 output. access instructions in the manual. Will take intervals less than 1 us apart. about $250 on ebay. Originally for hard disk drive measurements. Set up to use x10 probes; has a risetime calibrator. accepts 5 MHz external standard. During my search, found that Odetics had a patent on the interpoltion timing scheme. manual also at https://www.febo.com/pages/hardware/kode/kode_tia3100.pdf Don -- If you don't know what it is, don't poke it. Ghost in the Shell --- Noli sinere nothos te opprimere Dr. Don Latham, AJ7LL Six Mile Systems LLC, 17850 Six Mile Road Huson, MT, 59846 mailing address: POBox 404 Frenchtown MT 59834-0404 VOX 406-626-4304 CEL 406-241-5093 Skype: buffler2 www.lightningforensics.com www.sixmilesystems.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] E4437B phase noise spurs. Any ideas?
Hi Bill, Thank you for your detailed response. First of all, I'm happy with the SMIQ and I included that only to show that the spurs do not come out of the spectrum analyzer (which is an FSU indeed). Regarding the E4437B: You are right that the data sheet specs allow this but I find it rather unusual for such a high profile device, especially since it's the high spectral purity version. I have an E4432 (3 GHz and not designed for high spectral purity) and an SMIQ and they both do not show such strong and so many spurs. Also, the phase noise plots in the data sheet do (in my view) show fairly narrow features; at least don't look like highly smoothed plots. The E4437B spurs appear only above 2.4 GHz. Virtually no spurs are visible below 2.4 GHz. And they look quite exactly the same for every frequency above 2.4 GHz. Same offset, similar amplitude. Both when changing the frequency a couple of kHz and when changing by GHz. Also, I find that asymmetry relative to the carrier interesting. So what I would like to understand is if I caught an unlucky device of the E443x series and can expect to see better performance with other ones. Or if that is a pre-failure sign. And if other people are seeing them as well. Thanks, Wolfgang DL1SKY On 2015-07-17 07:47, Bill Byrom wrote: Hi, Wolfgang. Both of your generators appear to be well within their datasheet specifications based on the spectrums you posted. The datasheet for that ESG-DP (digital modulation with high spectral purity) model is at: http://cp.literature.agilent.com/litweb/pdf/5965-3096E.pdf The E4437B nonharmonic spur specification is on page 5 (use the ESG- DP columns): So according to that table, above 2 GHz the E4437B spurs at 3 kHz offset **should be below -68 dBc**. It appears to me that the largest spur at such offsets (at about +3.5 kHz offset from the carrier) is **actually about -74 dBc**. The largest spur is about -63 dBc at +1 kHz offset (which is closer than the spur specs). The RS SMIQ03B specs are: The SMIQ03B nearby spurs in your screen capture are at about +/- 9 kHz offset from the carrier (about -85 dBc), so are too close to be covered by the spec above. The spurs at 10 kHz offset are about -90 dBc. I'm guessing that the spurs might be affected by several adjustments performed during factory alignment. In most modern complex instruments (including both of these signal generators, I believe) there are far too many alignments to be made by a human, and a long automated process using a rack of equipment is used to align the instrument and store certain constants in nonvolatile memory in the instrument. But there is no reason to worry based on your results, since they are well within instrument specifications. So ... assuming that the spurs aren't coming from your spectrum analyzer or other sources (and I'm guessing that's a FSU which is very good), both generators appear to be within specifications (after warmup within the calibration interval, of course). * *The E4437B closest spur covered by the 3 kHz spec is at about +3.5 kHz, and it's about 6 dB better than the spec.* * The SMIQ03B has a 6 dB better spurious spec than the E4437B between 2 and 3 GHz, but the SMIQ offset for their spur spec is wider than the ESG (10 kHz rather than 3 kHz). * At other carrier frequencies the spurs may be higher or lower in amplitude (and at different offsets). Try tuning the frequency in 1 kHz steps over a wide range -- I would guess that the spur offsets and levels will change in a complex fashion due to the synthesizer. * The phase noise specifications normally apply to a smoothed trace and do not include narrowband spurs such as the ones you see in your screen capture. -- Bill Byrom N5BB Tektronix RF Application Engineer On Thu, Jul 16, 2015, at 04:15 AM, Wolfgang DL1SKY wrote: Hi, I just got a used/refurbished E4437B which I wanted to use as a all-purpose RF generator primarily for 3-4 GHz. Unfortunately, I'm seeing strange spurs for frequencies above 2.4 GHz, see the green curve in the attached image. The yellow curve is an SMIQ03 for comparison. Observations: - For frequencies below 2.4 GHz none of the spurs appear. - It has an OCXO and I left the device in standby (oven on) for 12 hours. - If I leave the device ON for 1-2 hours, the spurs go down. Anybody else seeing this? Any ideas how to fix this? Does this look like a pre-failure sign? Regards, Wolfgang DL1SKY _ 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. Email had 1 attachment: * E4437B-phase_noise_problem-1.png 34k (image/png) ___ 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] how to find low noise transistors (was: Firmware and antenna for Stanford Research FS700)
I agree with Bob, find a vendor you can trust and make sure you buy from an authorized distributor or if just need two or three parts try to get them as samples.directly from the manufacturer. The reason for this is you may get a fake or reject part and you will never know. Trying to do the measurements yourself is pretty much out of the question today.. Every improvement made it harder in that the equipment had to itself be lower in noise If interested https://scholar.google.com/scholar?q=measuring+transistor+noisehl=enas_sdt=0as_vis=1oi=scholart . -pete On Sat, Jul 18, 2015 at 5:29 AM, Bob Camp kb...@n1k.org wrote: Hi You have (and always have had) two basic choices: 1) Buy a very expensive part from somebody who has gone to the trouble of characterizing the noise performance and will guarantee at least some of what they show on the data sheet. 2) Buy a bunch of cheap transistors and test them. Lock in on a specific part and vendor. Keep monitoring what you get in case they “improve” their process and the magic goes away. How do you select candidates? That’s never been easy, there is less and less data on the sheets every day. Normally the first step is to look at a vendor that you have had luck with in the past. The next step is to ask them… Bob On Jul 18, 2015, at 5:16 AM, Attila Kinali att...@kinali.ch wrote: On Fri, 17 Jul 2015 23:25:10 -0400 Charles Steinmetz csteinm...@yandex.com wrote: A pair of Zetex (Diodes, Inc.) ZTX849 or FZT849 actually have significantly lower voltage noise than either the LM394 or MAT12. I always wonder how you figure out whether a transistor is low noise or not. What part of the datasheet hints at which transistors have low noise and which have not? Even if it's just try and measure, how do you find good candidates to measure? Attila Kinali -- I must not become metastable. Metastability is the mind-killer. Metastability is the little-death that brings total obliteration. I will face my metastability. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the metastability has gone there will be nothing. Only I will remain. ___ 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] Loran C returning to a station near you...
Bill I will let you know what the Austrons say for signal level. Fact is they locked up fast. My FS700 is taking its time. Graham it will sound different as there are no competing stations on other GRIs. Thats the very first thing that hits you. Additionally its only 1 station. But that same station is sending the master and secondary delayed emission. Its simply not the same ole sound. But it still works very well for checking frequency. Regards Paul WB8TSL On Sat, Jul 18, 2015 at 12:52 PM, billriches bill.ric...@verizon.net wrote: Correction on times for Mon - thurs - start 900 edst - 1300Z -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Saturday, July 18, 2015 7:05 AM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1300Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] Loran C returning to a station near you...
As expected, loud and clear near Ottawa Canada, approximately 380 nautical miles. It does sound different from my recollection of Loran. However, this is only one station transmitting where as before it would have been several at the same time with different GRI's. cheers, Graham ve3gtc On 2015-07-18 11:04, billriches wrote: FYI Wildwood eLoran will be fired up 1300Z Saturday (today) and 1900Z Monday thru Thursday. Happy listening. Any reports would be appreciated and I will pass them along to the engineer that is driving the train. 73, Bill, WA2DVU Cape Mahy -Original Message- From: billriches [mailto:bill.ric...@verizon.net] Sent: Thursday, July 16, 2015 10:04 PM To: 'billriches'; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] Loran C returning to a station near you... FYI GRI for Wildwood is 8970. Bill, WA2DVU Cape May --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ 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] how to find low noise transistors
-Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of KA2WEU-- - via time-nuts Sent: Saturday, July 18, 2015 3:40 PM To: time-nuts@febo.com Cc: akpod...@synergymwave.com; alexander.r...@rohde-schwarz.com Subject: Re: [time-nuts] how to find low noise transistors BFG540 That's what I mean -- both BFG540 and BFG591 have been discontinued by NXP. Guess they don't sell enough of them these days. -- john, KE5FX Miles Design LLC ___ 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] how to find low noise transistors
BFG540 In a message dated 7/18/2015 6:37:34 P.M. Eastern Daylight Time, j...@miles.io writes: Last time buy 31-Dec-15. :( Have you heard of any good substitutes? I've built a lot of amps with BFG591s, and they also got the axe recently. Small-signal RF bipolars seem to be an endangered species. -- john, KE5FX Miles Design LLC ___ 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] how to find low noise transistors
Good afternoon, another low noise recommended transistor is the http://www.cel.com/pdf/datasheets/ne856m02.pdf and for frequencies below 10 Mhz the 2N2857. This nice fact is that the AF and KF values are published, the bad part is the the AF=1 value violates the law of physics. http://www.microsemi.com/existing-parts/parts/47966 http://espice.ugr.es/espice/src/modelos_subckt/spice_complete/RF.LIB Be careful ! Who says EE is easy. Best regards , Ulrich N1UL In a message dated 7/18/2015 3:56:53 P.M. Eastern Daylight Time, time-nuts@febo.com writes: Good afternoon, There is a problem in the literature that people confuse the spot noise figure and the large signal noise properties. Here AF and KF needs to be known and considered. Here is the mathematical correct formula in a Word for Windows Form attached file. If you use it for publications, please quote me . Thanks My advise is take a BIP transistor , fT not much more then 20 x operating frequency (lower flicker component) and operate it at 15 to 20 % of ICmax. The BFG540 is amongst the best Oscillators oscillators http://www.nxp.com/documents/data_sheet/BFG540_X_XR_N.pdf Now you outperform most colleagues 73 de Ulrich N1UL x In a message dated 7/18/2015 1:19:57 P.M. Eastern Daylight Time, p...@petelancashire.com writes: https://scholar.google.com/scholar?q=measuring+transistor+noisehl=enas_sdt =0as_vis=1oi=scholart ___ 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.
