Re: [time-nuts] 10811-60111 needs repair
On 2/24/2014 8:26 AM, Tom Holmes wrote: Is there anyone on the list who repairs these guys. The one I have is dead and I would like to get it going again. Tom, the most common fault with these is the thermal fuse going open circuit. If that's your problem then fixing it yourself might be easier than sending it out... I had one with a dead thermistor; that was a little bit trickier. A lot in the archives on these, I'm sure. Dan ac6ao ___ time-nuts mailing 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] Ublox 7
On 5/24/2014 7:22 AM, ewkeh...@aol.com wrote: Having used lately ublox 6M for GPSDO work I decided to buy a couple of MAX 7C's on ebay for $ 16.00 181293242043 Super results. Now listed as: 171339542977 Dan ___ time-nuts mailing 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] HP 5335A counter top cover
On 6/13/2014 12:58 PM, Russ Ramirez wrote: I just acquired one of these on the cheap but when I received the unit, it did not come with the top cover. I'm reaching out to see if any of you would have one from a parts mule, or one you might think would fit. For example, the top cover of a 8640 is the same design, but I'm not sure it's the exact same size. It's not, the 5335 is a bit less deep than most of that series instruments at around 12.5 inches as opposed to the 15.5 of the 8640B, and I'm sorry, I don't have a spare. I don't have any others with that depth. Dan ___ time-nuts mailing 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] HP 8568B
On 6/28/2014 6:48 PM, Hui Zhang wrote: Hello all: Rencently I bought a second-hand HP8568B Spectrum Analyzer, it kind of vintage but works well. Only problem is its time base lost accurate. When I use it measured my HP Z3801A output (locked to GPS), the center frequency read is 9.12MHz, about 88Hz diffrence. So I decide to use my Z3801A for its external reference. When I connected the cable and set the reference switch in rear paneal to EXT, the CRT displayed EXT REF, I believed it worked. But when I use it measure a nother GPSDO (Trimble ThunderBolt locked to GPS), it still have 42Hz diffrence. I am very sure both of my two GPSDO is good, if I use my HP53132A counter to compare them they will has less 1E-10 (1mHz) diffrence. And then I tie a BNC three-way connect from my Z3801A, one way to 8568B's EXT stand input, one way to the signal input in front panel, the diffrence is still 42Hz - it's 10.42MHz. I was fully confused, do I need a calibration after I used external 10Mhz stand? I read the manual again but not fou nd any infomation about how to do it. What do I do now? Anyone give me a suggestion? Any infomation will be appreciate. Hui Zhang, check the supplies from the A24 board. The oscillator +20V supply is supposed to turn off when Ext is selected. Also the series transistor for the heater supply I feel is very under rated; I mean feeding an oven heater through a 2NA sounds like a good idea? It could be that you have the internal Osc still working when Ext is selected. Also the older Ovens fitted to those are not the most reliable ones ever made. I reported on the opening up and repair of one in an 8568B of mine about six months ago but that may have been on the -hp- list, not here... Good luck! Dan ac6ao ___ time-nuts mailing 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] 10811 Thermal fuse?
I'm sure this has been discussed to death before, but does anyone know of a source of thermal fuses small enough to fit in the -hp- 10811? I have found plenty of larger ones, none of which will fit and would rather not just link it out. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10811 Thermal fuse?
On 9/2/2014 12:23 PM, Dan Rae wrote: I'm sure this has been discussed to death before, but does anyone know of a source of thermal fuses small enough to fit in the -hp- 10811? I have found plenty of larger ones, none of which will fit and would rather not just link it out. Dan ___ Thanks for all the tips and advice. The Chinese eBay ones (15A) I have bought before and they are physically too big to fit. Buerklin is a German distributor and will want 28 Euros to ship to the US. I know I can link it out, but don't like doing that in something that is powered on permanently. I have found some Panasonic ones that Digikey distribute in the US, but frustratingly the data sheets have no dimensions given. I have ordered some 1A and 2A ones to try, and will report further. I suspect that the originals would have been around 115C. And for searching they seem to be called Thermal Cut Outs (TCO), not fuses. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10811 Thermal fuse?
On 9/3/2014 12:23 PM, John Miles wrote: Was the oven in a runaway condition? Like Bob, I've never seen a situation where the thermal fuse has actually done anything useful. It seems like the inner oven will go into full-blown China Syndrome before the thermal fuse on the far side of the outer PCB gets hot enough to fail. -- john, KE5FX Miles Design LLC John, I have two now with open fuses; one where the thermistor went open and the thermal fuse did blow, and the other just the usual fatigue. So despite the layer of foam between the Oven part and the board it did get hot enough to blow in the one. With an open thermistor the oven stays full on. I am waiting on Digikey to deliver some 43 cent (in qty 10 plus postage) Panasonic 1A 115C fuses, so I should be good for my lifetime... I'd still rather fit these at that price rather than link it out even if the odds are minuscule... Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 10811 Thermal fuse?
Panasonic EYP-1BF115 Thermal Cutoff 115C 1A, part number P10912 from Digikey is a perfect fit to replace the original -hp- part. Dan ___ time-nuts mailing 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] WTB: GPS Antenna Splitter
On 10/8/2014 9:01 AM, Dave M wrote: John, I found a couple Mini-Circuits ZAPD-2 splitters on Ebay for around $22 each, i I found one at the local swap meet many years ago for $1. I used that for years when I only had two gps receivers and it worked fine. Opening up the top cover you will easily see the circuit. I cut one of the strip lines from the number two port and inserted a 100 pF DC blocking cap, and a 220 Ohm R plus RF choke (several turns of thin wire) to ground. Number one port Rx feeds the antenna and the Rx on Port 2 thinks it has an antenna connected. With a well sited antenna you will not notice the 3 dB loss. Now with an 8 way -hp- splitter ($10 at the swap) I don't need it any more, but the disadvantage is that one is tempted to try to use all those ports :^( Dan ___ time-nuts mailing 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] FE5440E Cesium parts wanted
I'm looking for the A12 18V power supply and A8 secondary 5 MHz OCXO modules for an attempt to resurrect my Cesium unit before it gets too heavy for me to wrestle with... Does anyone have a parts unit or junker that they might be able to supply these from please? Thanks, Dan ___ time-nuts mailing 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] KS-24361 10 Mhz mod interesting document
On 11/19/2014 2:47 PM, paul swed wrote: Was doing a search for Lucent RFTGm-II-XO looking for alternates to the $150 solution. A 10 Mhz mod popped up. http://telcodata.us/~myself/Lucent-RFTGm-Modification.pdf Looks simple enough and I have not validated anything. Regards Paul WB8TSL Paul, that has nothing to do with the current ebay offerings that have generated so much traffic recently... Dan ___ time-nuts mailing 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] -hp- 5065A battery pack
I've just finished fitting new cells into my 5065A battery pack. A bit of a struggle since it is quite a tight fit to re-use the original plastic container. For information, the only cells I could find that just about fit, and even then one has to remove the plastic covering from them, were the tabbed version of part number CD-SC2200P from BatterySpace.com. These are 2200 mAH Sub C NiCads, so very similar in capacity to the originals. Total cost including tax and shipping, was around $60 for the 21. Southern California Edison can now resume their normal abysmal service... :^) Dan ___ time-nuts mailing 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] -hp- 5065A battery pack
On 12/4/2012 3:51 PM, Bob Camp wrote: Hi How much backup time does that battery pack give you? Bob Bob, it's at least what they claim in the manual for that Option, something like fifteen minutes from what I remember. Dan ___ time-nuts mailing 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 far can I push a crystal?
Having just adjusted a crystal oscillator at 10.715 MHz, I would hazard a guess that the most one can easily pull a crystal of nominal frequency around 10 MHz would be of the order of +/-1 kHz. Certainly not 60 kHz. dr ___ time-nuts mailing 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] Racal 9420 OCXO schematic?
On 2/5/2013 6:00 AM, Marco IK1ODO -2 wrote: The subject says it all: anyone has the schematic of the Racal 9420 OCXO? A friend has one that stopped oscillating, and want to give it a try. Marco, there is a man in Wales who offers these schematics for sale [1] and also repairs 9087 signal generators. He has never replied to several emails I sent him, so good luck! I have had several failures in the smaller 9442 OCXO, all of which, among other things had hardened and brittle very fine PVC wiring into the inner parts. It is worth looking at this first of all and replacing it with Teflon / PTFE wring, if necessary. I have the circuit for the 9442, but haven't yet had a need for doing the much more complicated 9420. Touch wood. Dan [1] for about what you would pay for the OCXO on ebay. ___ time-nuts mailing 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] FRK-L Rubidium
Since we're offering up faults for the FRK, I'll add one that I've found: there's a CMOS 4060 oscillator that should go off at 8.128 kHz, set by an adjust on test R. If this drifts off enough the lock will never happen. It provides the FM frequency for the synth. Dan ___ time-nuts mailing 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] GPIB counter logging / plotting software?
I am working on 400 - 500 MHz DDS clocks for an amateur radio project and would like to record over gpib and plot the relative frequency drifts over time of different versions of the oscillator from a cold start. I have Racal 1992 and -hp- 5345 counters available, themselves driven from gps. I have the prologix USB thingy. Does anyone know of any software that will enable me to do this, without spending lots of money? Dan ___ time-nuts mailing 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] GPIB counter logging / plotting software?
On 2/25/2013 8:15 AM, John Ackermann N8UR wrote: John Miles' most excellent TimeLab software should be able to do what you want: http://www.miles.io/TimeLab/beta.htm Thanks, John and everyone else who responded. I should have known John Miles would have the answer :^) All the best, Dan ___ time-nuts mailing 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] GPIB counter logging / plotting software?
On 2/25/2013 11:02 AM, John Miles wrote: I'm not sure about the Racal, but the HP 5345A can be placed into talk-only mode and used to stream readings to TimeLab in Acquire-Acquire from counter in talk-only mode . JohnA's link is the right one to use. The advantage to trying it with the HP 5345A is that I have one around here, so I can reproduce your setup if you have trouble getting it to work. Should be pretty straightforward, though. -- john, KE5FX Miles Design LLC John, I'm sorry, a senior moment there, it actually is the 5335A that I was thinking of, although I do have one or two 5345s and an ailing 5370B in the garage as well. The 5335A was dragged out, your program loaded, and I'm doing a 1 hr run as I type, as excellent as I thought it would be. Many, many thanks John! Dan ___ time-nuts mailing 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] hp 5065a life ?
Dott. Alfredo Rosati wrote: Is there a way to assess what remains life of hp 5065a Rubidium lamp ? I bought a 5065a is arrived in excellent condition almost like new. The only incorrect parameter was the value 2arm, over 50, after a tuning of R1 now is around 40. everything works very well, but I'd like to know how much life have more ? is possible or only the time replay me. Probably as much life as you have left Dottore, they don't wear out or get used up like Caesium. Components in them may die like with any electronics, but the lamps should last as long as you :^) They are a lot more reliable and accurate than the small newer Rb standards for sure. I am sure mine will outlive me. Dan ___ time-nuts mailing 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] Interesting piece on BBC news
About vulnerabilities of GPS. http://news.bbc.co.uk/2/hi/science/nature/8533157.stm nothing exactly new however. Dan ___ time-nuts mailing 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] HP10811 taxonomy?
Charles P. Steinmetz wrote: Has anyone compiled a taxonomy of the apparently numerous variants of 10811 OXOs? (Distinguishing features, rated performance, used in what instruments, etc.) Charles, if you have not already seen it there is a manual, I think on the Time Lord, TvB's site that has an appendix listing all the varieties of the 10811 and thus how they were selected, which makes interesting reading. Dan ___ time-nuts mailing 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] Do you have HP5065A units for sale? If so, please contact me directly. Thanks!
Bill Hawkins wrote: Peter, cheek is not the problem. The problem is that all of the Rubidium Vapor Frequency Reference assemblies have darkened with age, unless they've been rebuilt or replaced. I'm not so sure about that. There are quite a few of us time nuts that own 20 plus year old 5065As that are still performing as well as the day they were built. Darkening? Peter, if you are serious then keep an eye on the sky, or rather on eBay, they do turn up from time to time in the US at sensible prices, but in the UK I have no idea.I was lucky maybe in that the seller thought there were bits missing from mine because there was a hole where the clock option would have gone... But I'm sure I wasn't the only one to know what it was. And the original poster had obviously been trawling through the -hp- list and e-mailing directly everyone who seemed to own one before coming to this list, as if anyone who cherishes these as much as we do would even think about parting with one :^) Dan ac6ao / g3ncr ___ time-nuts mailing 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] Do you have HP5065A units for sale? If so, please contact me directly. Thanks!
Robert Atkinson wrote: Changing the thread slightly, where do the Efratom FRK- L and H fit in the hierarchy of Rb quality? I guess somewhere between the telco units and the 5065A. Opinions welcomed! Robert G8RPI. Yes, but much closer to the Telco units than to the -hp- I'd have thought... dr ___ time-nuts mailing 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] GPS antenna splitters
ashle...@aol.com wrote: Hi Everyone After a lot of learning, sweating (yes, girls do sweat), hand wringing, and a LOT of emails and great help , we have two of Mr Miller (G3RUH) GPSDO units up and working fine. Disciplined 10mhz all over the place. Now what we need is a GPS antenna splitter. When I only had two gps units in the dim and distant past, I used a passive splitter made from a Minicircuits (MCL) ZAPD-2 unit bought at the swap meet for $1, with a 100 pF series blocking cap in one of the output ports. If the receiver connected to the other port complains, you can add some resistance to ground to fool it. There are more expensive ways of doing it... Dan ___ time-nuts mailing 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] schematics for a HP117a please
paul swed wrote: Just picked up 2 units at a flea market today. Would like to fire them up without smoke. :-) Would appreciate schematics if the are out there. My search so far is 0 Thanks Paul, to get these to work, you will need the loop antenna. This has, in the early versions at least, a Nuvistor amplifier in it with a crystal filter built in to it. I think there was a later version that had transistors. I have seen the schematic somewhere, have you tried TvB's site? Dan ac6ao ___ time-nuts mailing 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] Fluke Thunderbolt Monitor Revisited
gandal...@aol.com wrote: 3...The series input and base to ground resistors on the RS232 interface are both 180 ohms, rather than 10K and 3K3 respectively as in Didier's circuit. If one wanted to use the RS232 interface to a computer at the same time as the ko4bb monitor in parallel, which I often do, then you would be well advised to stick to Didier's original values there. RS232 is quite robust, but still... I built one here quite early on to the original design and it has performed flawlessly ever since. I can not for the life of me figure out what oriental logic dictated these changes in the first place. And well done Nigel for getting to the bottom of this! Dan ___ time-nuts mailing 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] Austron 2100 going...
I have a now useless 2100 Loran receiver / comparator here, does anyone have any use for this? Before I recycle it. (Here is southern California.) Dan ac6ao ___ time-nuts mailing 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] Wanted dead oven T'bolt
I have an insane desire to marry up a T'bolt with an E1938 OCXO which I have here and can't think of a better use for. Does anyone have a T'bolt with a duff or dead OCXO? TAPR reject pile maybe? Best wishes Dan ___ time-nuts mailing 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] Austron 2100 going...
Dan Rae wrote: I have a now useless 2100 Loran receiver / comparator here, does anyone have any use for this? Before I recycle it. (Here is southern California.) The Austron is on it's way to a good home where it may still work. dr ___ time-nuts mailing 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] Austron 2100 going... Gone!
asma...@fc.up.pt wrote: Hello Dan, If it is a 2100T I would be glad to adopt that child. Antonio, as I thought I said before, it is on it's way to a new home. Dan ___ time-nuts mailing 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] RACAL-DANA 1992 Option 04E problems
bill...@aol.com wrote: I own one RACAL-DANA 1992 (Standard- TCXO). I purchased one with the Option 04E on eBAY. The 04E chassis is sealed and the internal OCXO overheats due to lack of cooling air. This causes the counter to stop taking measurements. I had to add ventilation holes on the top and right side of the chassis lid to obtain reliable operation. Both counters work up to 1,750 MHz. Bill Hanna Bill I have had several of these through my hands over the years and the outside of the crystal oven does get hot but not exceptionally so. Certainly it should /not/ require any extra ventilation. I would suspect that you have a faulty oven heater controller in there and that the heater is running at full current all the time. What frequency does the standard put out? The frequency and the current drawn by the oven should both settle down after about 15 minutes from cold. Also if you really meant 1,750 MHz on both inputs that's way better than it should be, pretty amazing really :^) Dan ___ time-nuts mailing 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] (no subject)
Bob Camp wrote: Hi Simple answer - they self calibrate to 1x10^-13 at a one day time period. Essentially zero long term drift. Bob Have I missed something? A self calibrating cheap Rb unit? a self calibrating 10811? I really must wake up :^) dr -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Mark2 Sent: Thursday, August 19, 2010 4:49 PM To: time-nuts@febo.com Subject: [time-nuts] (no subject) Sure they're good but other than it's a really cool and stable oscillator why is everyone bothering with these when you can get a decent LPRO Rubidium for the same or less . It at lest ten times more stable than the HP oven job. I just bought 5 good LPROs on Ebay for about $200.00 plus shipping... Mark ___ time-nuts mailing 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] What's the lifetime for a HP Z3801a?
My Z3801A is quite happy still plugging along at 35,208 units of life time... dr ___ time-nuts mailing 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] slightly OT: EADS/Racal 1991 opt 55M
On 9/9/2010 7:03 AM, p...@pseng.org.uk wrote: I'll second the thanks to EADS (and David). I too used too look for support for older equipment when buying for day job. Currently struggling with opt55M ie the miltary coding CIL/MATE etc for a stack of 6 1991's for TI use. Any pointers on using CIL/MATE would be much appreciated. Phil, I'm pretty sure there's a link that you can move inside to convert these to standard gpib, at least in the 1992 there was. This was covered in the past here I think. Have you checked the archives? Dan ___ time-nuts mailing 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] Questions about HP 5370B
On 9/14/2010 1:23 AM, John Miles wrote: As Bruce suggests, you'll want to peek inside to see that you really do have a 10811 oscillator. If so, then it sounds like the thermal fuse (F1, inside the 10811) might be open. Just short it out, or if you like, put in an NTE part with a similar temp rating. It serves little or no useful purpose. -- john, KE5FX I hate to disagree with John who knows a heck of lot more than I ever will, but in this case it will protect the oven from cooking up if the control circuit fails with the heater full on, which can happen. I did have a 5370B with a 10811 that had a bad thermistor in it as well as an open fuse. I'd guess that's why -hp- fitted it. But yes, the thermal fuses can and do fail open for no good reason, and it sounds like this has happened here, but I would not recommend shorting it out permanently. Dan ___ time-nuts mailing 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] T'bolt and E1938A
I am about to marry a T'bolt with an E1938A and wonder if anyone has any idea of good starting values for TC, Damping and gain? Thanks, Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt temperature spikes
Mark Sims wrote: I set up my ThunderBolt data logger to flag temperature spikes. Over a 10 hour run last night it caught five of them (TOW magnitude): 104416 0.097 deg 104898 0.022 deg 115715 0.087 deg 135298 0.098 deg 138564 0.041 deg This is a spike? Surely this kind of tiny temperature variation on the unit's board somewhere outside the oven does not have a lot of relevance or effect on anything inside the oven where it is all happening. And what is the tolerance and resolution of the temperature measuring device anyway? Or am I missing something fundamental here? I have long since stopped monitoring mine since it seems quite happy to be left alone, but I used to see diurnal variations in temperature reading several orders of magnitude greater than those spikes. Dan ___ time-nuts mailing 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] Austron 2100 keypad?
My 2100 timing receiver (no suffix) has started to give me problems with what looks like bounce from the keypad switches, with a lot of numbers repeating without being asked. Is this a known problem with these units, and is there a known fix? I don't think the guts of the pad are accessible for cleaning. Thanks, Dan ___ time-nuts mailing 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] Austron 2100 Loran-C Frequency and Timing Receiver
Skip Withrow wrote: Well, my Austron 2100 seems to have bit the dust. snip There are some software diagnostic routines in the box. The RAM test runs fine, but it appears that I get an error on the EPROM test. The test generates an E-20 error. The book states that if the EPROM test fails it will give an E-21, but nowhere do I find any hint as to what an E-20 error is. Skip, according to my manual, and I quote directly: An output of E-20 indicates a properly functioning EPROM. An output of E-21 indicates that one or more of the EPROMS are bad. Page 6-12 As to why they bother to have an 'error' message for a good eprom, well, there you have got me. The next time I have a chance I can certainly get into mine and read the EPROMS, but I suspect your trouble lies elsewhere. My experience with older microprocessors in radios at any rate, is that if an EPROM dies, then you will not be able to run any test routines anyway :^( Dan ac6ao / g3ncr ___ time-nuts mailing 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] Checking accuracy of Rubidium standards
Randy wrote: I was wondering if it is worthwhile or even feasible to compare an LPRO Rubidium standard against a Z3801. Since their frequencies are probably going to be extremely close anyway it would seem some special method/equipment would be required for high precision. Suggestions? Randy, As I have just been doing this, I'll offer my 2 cent's worth. The problem I found is that the Rb standard, in my case an hp 5065A, has better short term stability than the gps unit. So for getting down to the best accuracy that the Rb unit is capable of requires integration of some kind over a longish period.I find using a pen recorder on the IF output of a mixer, with crude LP filtering on it will permit setting an Rb standard with confidence down to the 10 e -11 level. For approximate setting, triggering a double beam scope from your reference with the time base at it's fastest setting and the x 10 magnifier in, and the gain on the channel with the unit under test wound right up to give near vertical zero crossings, will enable you to see small phase shifts of the unit under test. With the 465B I was using for example that's 2 nanoseconds per major division But it gets tiring watching it for a long time :^) Fun though! Dan ___ time-nuts mailing 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] To improve a Tbolt?
I have been reading with interest John Miles' page about his Tbolt 'upgrade'. http://www.thegleam.com/ke5fx/tbolt.htm I have a newly acquired Tbolt here, and also have lying around an almost identical 10811-60111 OCXO which I am considering using with it, exactly as John describes. However my Tbolt is of a later vintage than John's (2005 date code) and I wonder if that would show as big an improvement as John reports. The on board OCXO on this one has a Trimble sticker on it, but otherwise looks similar to the one pictured on John's page. The GPS receiver area of my board also looks very different, but I don't think this would have any effect. Not having the sort of phase noise measuring facilities here to be able to test it, I am wondering if anyone else has done this with a similar vintage Tbolt, and could say if it is likely to show as big an improvement as John seems to be getting. I was a little surprised at the amount of short term variation, of the order of minutes duration, that I was seeing on another Tbolt when using it to set a Rb standard. The obvious answer to my question is to try it and see, but I'd appreciate hearing from anyone who has tried it! Dan ___ time-nuts mailing 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] To improve a Tbolt?
John Miles wrote: I've upgraded the graph on the http://www.ke5fx.com/tbolt.htm page to show the performance of my Thunderbolt from the TAPR group buy (in orange) next to the traces for my older unit before and after the 10811 upgrade. Thanks John, it looks like the Tapr ones have a very good oven fitted already, and thus I will leave well alone. There must be something else I can use the 10811 for :^) Dan ___ time-nuts mailing 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] Wenzel Associates 100 Mhz osc
Lux, James P wrote: Just send Wenzel an email and ask them. James, they might answer you with your email address, but when I e-mailed them, several times, to ask the price of one of the OCXOs they advertised as being in stock, I never got an answer... I suspect they have anti individual time nut spam filters :^( What I did when faced with one of their custom 10 MHz ovens, was to find the stock model that it most resembled, and then a bit of Ohmmeter measuring confirmed that it indeed had the same pin out. This may not be possible if it is an older one of course. Good luck! Dan ___ time-nuts mailing 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] Build my own dist. amp ??
Dave M wrote: Randy, There are a couple distribution amp projects on the RealHamRadio web site (http://www.realhamradio.com). One has 8 isolated 75-ohm outputs; the other has 3 non-isolated outputs. Here are the links to each: http://www.realhamradio.com/10mhz-video-amp.htm http://www.realhamradio.com/g8lmx-amplifier.htm Dave, the problem with those, and indeed the TAPR kit eventually, is that all the Maxim ICs involved have been discontinued, and are no longer easily sourced. dr ___ time-nuts mailing 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] Programming an 8051 for Didier's Tbolt monitor?
Can someone here in the US kindly do this for me? I have the blank DIP IC, 20 pin version, but none of my old eprom programmers or PIC programmers will talk to it, and I didn't really want to buy or build something just for this one task... Dan ac6ao / g3ncr ___ time-nuts mailing 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 TOCs this year
I have reset my Austron 2100 to the new UTC time, but the TOCs given by the USNO seem to be off. Should I maybe assume they have not allowed for the extra second and subtract one second from the posted times? Can the US Navy have got it wrong? Tbolt got it right... Dan ___ time-nuts mailing 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] Radio clock fails to leap
Scott Newell wrote: My low-end Radio Shack 'atomic clock' did not handle the leap second. It will, just give it time. (Sorry!) Those normally sync up once a day around 3AM local, so will catch the daylight savings hour change but not the leap seconds as they happen... dr ___ time-nuts mailing 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 TOCs this year
Dan Rae wrote: I have reset my Austron 2100 to the new UTC time, but the TOCs given by the USNO seem to be off. Should I maybe assume they have not allowed for the extra second and subtract one second from the posted times? Can the US Navy have got it wrong? Tbolt got it right... Answering my own post, yes, that did it. The Navy got it wrong... dr ___ time-nuts mailing 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 TOCs this year
Tom Van Baak wrote: I have reset my Austron 2100 to the new UTC time, but the TOCs given by the USNO seem to be off. Should I maybe assume they have not allowed for the extra second and subtract one second from the posted times? Can the US Navy have got it wrong? Tbolt got it right... How do your TOC's compare with the one here: http://www.leapsecond.com/java/gpsclock.htm /tvb Yes, yours are correct Tom, it shows 01 10 05 for the next; while the USNO has 01 10 06. My Austron is happy now with the 1 second correction. I'll know where to look next time I need one after a power outage... dr ___ time-nuts mailing 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] 10 MHz Band-Pass Filter Needed
Richard W. Solomon wrote: The GPSDO I want to use has an output rich in harmonics. In some cases that is good, but Murphy rules and in the application I have today, it is not good. I need a 10 MHz Band-Pass Filter, Bandwidth is not critical, something small with SMA connectors would be ideal, but I can live with BNC. Anyone have such a beast or know where I can get one ? I checked Mini-Circuits and choked on the price !! Dick, it is really easy to build one. The wonderful (free!) filter design program ELSIE will give you all the help you need. I would have thought an hour or so with a couple of toroids would do the trick. Even just a Low Pass filter would usually do to turn a square wave into a sine... Dan ac6ao / g3ncr ___ time-nuts mailing 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] Wenzel Oscillator Repair
Ed Palmer wrote: Does anyone have any hints tips on how to open or repair one of these soldered-can oscillators? Ed, I have opened and repaired several sealed oscillators, OCXOs and TCXOs, as well as crystal filters, with some success. In fact the Isotemp OCXO in my homebrew GPS standard is still going strong after I replaced the TL431 regulator in that ten years ago. What I do is to use a box cutter type knife on the seams, side by side, repeatedly scraping out as much of the solder as possible. After a while the seam can usually be opened up enough to break any remaining solder towards the corners. I think the fact that this avoids any prolonged heating is probably the main advantage of using this method. It takes time, but so far I have not found one that wouldn't open in the end... Do I have to say: be careful and always work away from your fingers? It works for me at any rate, and by not using heat you avoid any extra damage :^) Dan ___ time-nuts mailing 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] -hp- 10811 repair (Thermistor)
The 10811-60111 that came in my 5370B counter turned out to have an open circuit Thermistor in it. This is a non-replaceable part in theory. However, nothing to lose, I have successfully substituted a Digikey Part number: 317-1371 100 kOhm 1% Thermistor ( from Cantherm, part number: MF51B104F3950 ). I measured the resistance of it at the target oven temperature, working back from the selected value of R20 that was installed in mine, in this case 0 Ohms for 84C. In fact this thermistor must be very similar to the one used originally, since I only needed to use a value of 110 Ohms for R20 to get bridge balance, instead of the short that was in there previously. Good enough for me... Dan ___ time-nuts mailing 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] -hp- 10811 repair (Thermistor)
Bruce Griffiths wrote: Meanwhile, before posting a correction I was trying to find data on the oven setpoint temperature tolerance. The relevant HP Journal with an article on the HP10811A is: http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1981-03.pdf One concern is: How accurate does one' thermometer which one uses to calibrate the thermistor bridge setpoint have to be? Bruce Bruce, I'm guessing that since they quote values of R20 in the manual in intervals of 0.1 Degrees, that is how close they got. Except oddly enough for 83.9 and 84.0 degrees, which are the same, but shouldn't be, IMHO. I don't claim to have got that close in my thermistor tests, maybe 0.5 degrees using a lab type mercury thermometer. But my original point is still valid: I now have a working oven. In my case I will use an external reference for the 5370B so it is kind of not that important anyway... Dan ___ time-nuts mailing 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] HP 117 paper ?
Pete Lancashire wrote: Does anyone know if the chart paper is still available ? I got some many years ago from a local electrical wholesaler in LA, the name Granger comes to mind. It wasn't cheap then, something like $40 a box, but it moves slowly :^) Dan ___ time-nuts mailing 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] Chart recorder consumables (was HP 117 paper )
Further to my earlier note, this paper was used in a number of other instruments, Truetime for one. The Box of Rolls I got way back was made by Amprobe. I just found a bit of it I had used as a bookmark, and it has a Catalog Number printed on the edge: 830AV600. Dan ___ time-nuts mailing 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] E1938 question
I have one of the Chinese E1938 modules I bought about a month ago. I just tried it out on the bench, and have not had much luck with it. The 5 Volt supply never goes above 50 mA or so, none of the heaters seem to be powered looking at the hockey puck D-sub connector pins. The four leds up by the PIC (?) seem to flash once on switch on and then pulse about once a second. The other led which seems to be on the 5 V supply is on. It does oscillate, but very low since it never warms up. Is there any point in my trying to go any further with this? It seems pretty dead to me, the PIC maybe? :^( Nice museum piece perhaps, but a bit expensive for only that... Dan ac6ao ___ time-nuts mailing 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] E1938 PIC hex files?
I am beginning to think that the PIC in my Chinese Ebay 1938 is dead or at least injured. Does anyone have the hex files for this one? Blank PIC16C74As can be had and it may be worth my trying to program a new one. Nothing else seems to make it work and as the PIC seems to be asleep, I'm not sure that attempting to talk to it with the serial program is going to help me much, but I will try. The part number is: E1938-80002 Dan ac6ao ___ time-nuts mailing 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] Connector For Trimble/Nortel GPSTM (NTGS50AA) ?
On 6/3/2013 7:57 AM, Frederick Bray wrote: So, I gather that most folks are just connecting power to the appropriate 2 pins on the 110 position connector. I wasn't sure whether people were wiring directly to the DC converter. Neither, in my case; I've connected to the fat PC traces that lead from the connector to the filtering and protection components. Others I'm sure will have done similarly. Incidentally, I have also taken a +12V feed to the distribution amp directly from the board, I reckoned it could spare the 40 mA or so that needs once the Oven warmed up. And another thing: I have two Thunderbolts here, one regular and and the other mated to an -hp- E1938 oven, and according to LH the Nortel outperforms them both. Dan ___ time-nuts mailing 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] BBC Precision: Measure of All Things
On 6/26/2013 6:53 PM, David Kirkby wrote: On 27 June 2013 01:45, Doug Calvert dfc-l...@douglasfcalvert.net wrote: The BBC recently did a three part series titled Precisoin: The Measure of All Things. Part 1 is Time and Distance Part 2 Mass and Moles Part 3 Is Heat, Light and Electricity Probably nothing ground breaking for any time nuts but may be interesting to watch with friends and amily. http://www.bbc.co.uk/programmes/b02xbjmf Note the BBC only makes programs playable for a short duration (I think 30 days), and there is only 5 days left. Even if you download a program, it wont run beyond its expiry date. Not that I suspect it would be too hard for a time-nut to circumvent it - set back the time of machine, run in a virtual machine etc. And BBC tv shows are not available (legitimately) for download or on demand outside the UK anyway. dr ___ time-nuts mailing 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] GPS antenna splitter
On 6/29/2013 11:35 AM, Graham wrote: I find my self in need of either splitting a current GPS antenna feed or putting up yet another antenna, I would prefer splitting the current feed. There are a few options one of which is a Mini Circuits ZAPD-2DC+ splitter/combiner whose data sheet specifically states DC pass through from one port to the combined port. Fair enough, this should work very well. However, there is another model, the ZAPD-2-N (having type N connectors) whose data sheet states neither DC feed through or not, in other words, it is does not say explicitly that it does or doesn't. I think the ZAPD-2-N splitter would work to split the antenna but I am sure about being able to feed the antenna through this splitter/combiner and was hoping someone could state yay or nay on that point. Graham, back in the past before I got the 8 way -hp- splitter I now use, I used an MCL ZAPD-2 (SMA connectors) for feeding two GPS receivers, and it worked very well. I left one port intact to feed DC to the antenna from that receiver, and put a small cap in series with the other to block that one. As the second gps connected to that port then complained I added a 220 Ohm R in series with a small choke to ground which lets that receiver think it is powering an antenna. Unmodified, there is a DC connection between all three ports which I think would not be a good idea for two receivers both looking for a powered antenna. If you can find one of these splitters cheaply, it's a very good way to go, but I wouldn't want to pay the new price for one :^) Dan ___ time-nuts mailing 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] HP 3325a 3325-18 service note needed
On 7/5/2013 7:34 PM, cdel...@juno.com wrote: My 3325A is having intermittent resets back to the power on default values. I ran across a reference to service note 3325-18 that relates to it. (my SN is in the range the note specifies.) Does anyone have a copy of the service note or know where I can access it? Corby, I don't have the service note, but I do have a late paper version of the manual which has, in the back dating section, notes of all the engineering changes by serial prefix. If you'd care to share your serial prefix, I could look and see if there is anything that looks relevant, and scan it. Dan ___ time-nuts mailing 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] Datum / Efratom MFTD Distribution units?
Does anyone have any details, schematics etc., on these units? I have two racks with various modules, both set up for multiple 5 MHz and 1 PPS distribution and would like to modify if possible to 10 MHz. I have found two versions of the MBF RF output unit, one with series tuned outputs as well as a 5 MHz MCL LPF inside, and the other with only the LPF. I have two versions of the input unit, one a BFI, the other a BFM. The BFM appears to do some 5 MHz filtering somehow, but I don't see any obvious frequency determining components... If anyone has done any investigation of these, I'd be glad to hear what the results were! Dan ___ time-nuts mailing 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] Datum / Efratom MFTD Distribution units?
On 9/1/2013 3:34 PM, Dan Rae wrote: Does anyone have any details, schematics etc., on these units? I have two racks with various modules, both set up for multiple 5 MHz and 1 PPS distribution and would like to modify if possible to 10 MHz. Replying to my own question :^) I have successfully changed the 5MHz MDP units over to 10 MHz. This turned out to be relatively simple; removing the Minicircuits 5 MHz LP filters revealed the PC board and silk screen had been laid out for a discrete 2 section LP filter, easy to populate as desired. The output circuits on each channel similarly seem to allow for different versions. I changed the 5 MHz series filters where fitted to 10 MHz ones by changing the L part to an appropriate value. The BFI / BFM input units appear to be broad band. Dan ___ time-nuts mailing 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] Doppler and FMT
On 9/19/2013 6:48 AM, quartz55 wrote: I was playing with SpecLab and my TS-2000 just to see how accurately I could measure frequencies in the HF region. I notice when I set the rx on cw and listen to the 750 Hz output of WWV at 15 or 20 MHz with SL, I get like 2 and sometimes more tracks about 2 Hz apart constantly shifting around. I assume this is Doppler going in and out? If that's so, how can anyone reasonably expect to measure any ionospheric HF signal in the mHz range? Dave, it's not that easy. I did the ARRL FMTs a few years back when they were transmitting from the other side of the States and thought I was doing well to get within 0.1 Hz. The phase shifts on 7 and 14 MHz I was seeing due to Doppler were up to 360 degrees, and quite rapid. Mind you I was using non computer techniques [1], so averaging by eyeball was possible. Also if you are using WWV / WWVH, here at least, you often get both signals at similar strength, so you might well be seeing two different offsets. Dan ac6ao [1] looking at the 100 kHz IF output of the receiver on a scope, both scope trigger and Rx reference driven by homebrew GPS unit. ___ time-nuts mailing 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] AD9850 boards
On 2/29/2012 1:42 PM, Don Latham wrote: Dunno if you have seen this on ebay: 260967834514 It's an AD9850 with a 125 MHz crystal mounted up on a .1 spacing board There are several vendors selling similar things. I bought a couple and have just pulled the 9850 off one for another project of mine. Build quality is a bit odd, and documentation is extremely variable to be polite. And the 9850 was good :^) Dan ___ time-nuts mailing 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] Antenna Position
And in any case, with four receivers, wouldn't a single aerial and a splitter be more economical and save on feeder costs? Mind you, having an eight way splitter as I do does tend to encourage gps proliferation :^) Dan ___ time-nuts mailing 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] Antenna for T-bolt
There's a lot of five Racal survey antennae on eBay, lot 370600485855 which have been round at least once before. I use one of these with a T'bolt and it performs extremely well; I'm not sure what one would do with the other four however... 5 Volt operation, TNC connector, c. 30 dB gain. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt Question
Ed, the message about leap pending refers to an impending leap second, in June I think but others may know more... It will happen and the message will go away. From your LH screen, I would say that your signal levels are way too low. I don't know why, perhaps low antenna gain, a badly sited antenna, even indoors maybe? I suspect the t'bolt is working as it should. You don't show your signal strength numbers, but here in Southern California with a well sited -hp- antenna, I see all visible sats with between 47 and 50 signal strength numbers and thus large circles on the map display. Dan ___ time-nuts mailing 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] Anyone from Italy here ?
And as a first step you might want to tell eBay. Contrary to the general impression they do care :^( Dan ___ time-nuts mailing 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] NTGS50AA, better than Thunderbolt
I just bought one of these. I was /really/ annoyed when I go to pay to find out that he has doubled the shipping fee since earlier this morning from $30 to $60. I'm not a happy camper... Dan ___ time-nuts mailing 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] NTGS50AA, better than Thunderbolt
On 5/3/2012 1:08 PM, Steve wrote: Did the seller double the shipping cost today? I could have sworn it was $30 the last time I looked at the listing. Steve Yes, he did. Unfortunately I didn't check since I still had the page open from earlier, and didn't find out till I went to Paypal... He certainly isn't getting positive feedback from me. Dan ___ time-nuts mailing 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] Oh dear
All this kerfuffle about that Rubidium Clock kind of misses the point. This is not some Audiophool thing but a serious piece of gear used for recording studios. I am not going to get into the pricing of it, but if you add up the cost of a /new/ Rb unit, distribution amp, power supply and back up batteries built into a case, it starts to add up. I see nothing odd about wanting to get the best possible source for the Master Clock for your master recordings. My son does run a small studio and for him I was able to make a version of that unit, for a lot less money of course. If he says it improves the sound of the recordings, and his customers agree, I am inclined to believe him. What could be more time nuts than wanting a precise clock? Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Morion Crystal Oscillator Double Oven
On 5/20/2012 3:27 PM, Chuck Forsberg WA7KGX N2469R wrote: Is this any good? Price on Ebay is affordable. It depends what you mean by any good. I bought one and it has what is to me, an unacceptable level of spurious signals on the 10 MHz output, some very close to the desired output. Not just the fundamental 5 MHz and 15 but others. There are some spectrum plots around that show this also, so it's not just mine. Dan ___ time-nuts mailing 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] Another Guatemalan NTG50AA
Mine came from near Esquipulas Palo Gordo 2,593 meters up on a hilltop. It works well with Tboltmon but I cannot get LH 3.0 to talk to it. There must be some trick that I am ignorant of... Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Morion Crystal Oscillator Double Oven
Mark, I was referring to the MV89A, yes, and I think the original query was to that as well. I presume mine is faulty and have not managed to get it open to investigate further, but the output on a spectrum analyser looks pretty grim, so it's in the big box of things to look at one day... Dan On 5/20/2012 4:29 PM, Mark Spencer wrote: If you are referring to the mv89 I can probably dig up some adev plots from one of mine if you are interested. Sent from my iPad On 2012-05-20, at 4:17 PM, Dan Raedan...@verizon.net wrote: On 5/20/2012 3:27 PM, Chuck Forsberg WA7KGX N2469R wrote: Is this any good? Price on Ebay is affordable. It depends what you mean by any good. I bought one and it has what is to me, an unacceptable level of spurious signals on the 10 MHz output, some very close to the desired output. Not just the fundamental 5 MHz and 15 but others. There are some spectrum plots around that show this also, so it's not just mine. Dan ___ time-nuts mailing 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] Morion Crystal Oscillator Double Oven
Mark, take a look at the plots on the following link: http://www.rbarrios.com/projects/MV89A/ which I think are from a list member. Mine is similar to the first of the group of three at the end of the page, not very pretty. What I assume is correct behavior is the second one. Dan ___ time-nuts mailing 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] NTGS50AA, better than Thunderbolt?
On 5/20/2012 7:56 PM, Mark Sims wrote: An interesting test would be to test a Nortel unit and a Tbolt with the same oscillator and see if the basic hardware had any difference in performance (I bet they would be very close) I had my Nortel running on the bench, in the open, for about 48 Hours, fed with a pretty good quality Lambda power supply. I suspect that any perceived diiference between it and the T'bolts may be down to the oven, which I suspect may be a double oven in the case of the Nortel. Due to the seller putting a sticky label on it helpfully saying used any identification has gone, but the size of it for it's age would indicate that it is something like the Morion inside. I don't see the temperature variation effects on the LH display that both my t'bolts show. It's performance at the 10,000 Tau level after 24 hours, with only the quick survey, and no tuning of any parameters was on a par with my T'bolt / E1938 and a little better than the standard t'bolt, all fed from the same antenna / splitter. It does, as Mark pointed out, see a better signal strength than the standard t'bolts, but as there are two RF amp stages visible on the board, with three filters, that doesn't surprise. I suspect the three LEDs grouped on the left of the little board may be more than just a power on indicator. Watching them and the LH 3.1 display with a cold start, I would guess that the red led is a cold oven / warm up indicator, and possibly the yellow one is a minor alert flag, with green being all OK. Only the imminent coming of the leap second will prove this one way or the other. The other two LEDs are steady green for phase lock, green flashing for recovery and the other, yellow, for holdover. These are all a bit delayed compared with the LH display. So, at the right price, worth getting, if you can live with the physical size and power supply needs. I'll be looking for a nice 2U case at the next swap meet. And many thanks to Mark for his swift LH changes! Dan ___ time-nuts mailing 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] NTGS50AA glitches
On 6/12/2012 12:25 PM, Charles P. Steinmetz wrote: Dan wrote: The attached LH plot shows what happened when it was moved slightly on the bench two or three times. What surprises me is that the DAC plot remains offset after everything else has settled. The movement event(s) appear to coincide with about 3 hours of significant temperature events. Both physical jostling and temperature may have an observable effect on the required EFC voltage. IME, the ~2 mV ECF shift seems somewhat high for normal jostling, but not beyond reason. Charles, the apparent temperature shifts were only caused by the movement, and were a surprise to me. The board is open on my bench in a room with an open window and the regular diurnal variation can be clearly seen and this has little effect on the performance. The movement of the unit was caused by my pulling slightly on the antenna coax by accident and then putting the board back in place. The last move was a deliberate one, but again was only a few inches on the bench. I'm not going to obsess over it; when I get the thing boxed up it won't be moving very far :^) Even with no optimisation of the settings, it still outperforms both my regular T'bolt and one I have that has an E1938 oven in it. Dan ___ time-nuts mailing 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] NTGS50AA glitches
On 6/12/2012 2:48 PM, Mark Sims wrote: I saw a similar DAC jump when I replaced the SMB pigtail to my board. The unit went into a brief holdover and came out with a shift in the dac vaue. I would try wiggling the coax connection (without moving the board) and also gently tapping around the board (maybe start with the oscillator can) with a screwdriver handle to see if anything causes an upset. Interesting. I just picked it up gently and rotated it through 90 degrees. This has produced another 1.5 mV DAC step and corresponding temporary jumps in the PPs and Temp traces. I seem to recall much bigger effects than this when adjusting ovens like the 10811 which I always would try to adjust in the orientation that they were to be finally used in, so I really shouldn't be surprised. Dan ___ time-nuts mailing 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] Vectron Type 229 Crystal Oscillator
I have a couple of Vectron 229-5657-1 OCXOs, nominal 80 MHz, that have a different pin out to that reported by Nigel. These have the SMA output and only a 24 V supply to pins 2 for + and 6 ground. No EFC. From the output spectrum, I think these are also doubling from a 40 MHz crystal. Dan ___ time-nuts mailing 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] US 5065A standby battery cell source?
All this discussion of the excellence of these Rb units reminds me that another cell must have died in my battery pack since the slightest glitch in the power here now makes the green light go out. The last time a cell died I just took it out since it actually seems to work well enough with 20 instead of the specified 21, but another one seems to have gone high resistance. So, my question is: where might be a good place in the US to get tabbed NiMH AA cells to replace the battery in mine? I am currently using generic Chinese ones, but am not at all happy with their longevity. And this one came from eBay, quite a bit less than $500 because it looked filthy, but it took a lot of patience to find it and a bit of TLC to get it going, but it has been working superbly for about four years now. Dan ___ time-nuts mailing 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] US 5065A standby battery cell source?
On 7/1/2012 5:51 PM, J. L. Trantham wrote: I have used Batteries America tabbed cells to make up packs for several pieces of equipment and have been well pleased. Joe Thanks both, they look a lot better quality than the ones I have... Dan ___ time-nuts mailing 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] Is this a cesium frequency standard?
On 8/23/2012 7:44 AM, David Kirkby wrote: Em, that's a lot of money for a Rubidium. I wonder what all the controls are for? It seems a complex rubidium compared to those that I've seen. David, if you compare it to the -hp- 5065A which last sold new for around $35,000 and upwards with options you will see the similarities. That was indeed in a class of it's own, a little better performance than the $100 ebay bricks :^) I've no idea how this Russian stuff compares, nor any great desire to find out. Dan ___ time-nuts mailing 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] US ebay sellers who won't ship outside the US
The problem here, more likely than not, is the restrictive provisions made by the US authorities over the end use of military surplus. It is not worth upsetting the men in black, believe me. A lot of surplus gear cannot legally be sold to a non US citizen, even with a US address. dr ___ time-nuts mailing 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] AC cord or connector for 5061A
J. L. Trantham wrote: If this means that the rotation can be 'user selected' as you assemble the connector, I am home free. I have not tried to disassemble the connector yet but will when I get back from work today. I bought one of these recently from Digikey for a 5065A (and for nearer to $25 than the $15 that tvb quotes alas ), and yes, you can take it apart and rotate the insert to the required orientation for the -hp- units. dr ___ time-nuts mailing 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] Method for comparing oscillators
ewkeh...@aol.com wrote: The only component I have trouble buying is the 74 AC 112. Newark has them, but you have to buy thousands. Material cost based on part searches is below $ 200.00. Digikey has them in stock for 68 cents US. dr ___ time-nuts mailing 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] TAC32 support?
Does anyone know if support for this is still available to those who bought it through TAPR? TAPR refer inquiries to CNS who do not answer my emails. It's not a big problem, simply that I upgraded to the latest version (2.7.8) only to find that I didn't have the password, and could not revert to the older version, 2.7.5, that I do have the password for because it had been over written. TAPR group emails seem to have ceased with version 2.7.6 I eventually tracked down an old version on a laptop, so all is well for me. But I don't advise anyone to upgrade without having the password :^) Dan ac6ao ___ time-nuts mailing 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] HP 5065A Rubidium
Brian Kirby wrote: Anybody know where I can find a PDF of the HP 5065A rubidium frequency standard ? Brian, assuming you mean the manual, Artek Media have one for sale, but it is for the older versions. I have never been able to find one for the later versions that use the 10811 OCXO. Dan ___ time-nuts mailing 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] HP catalogs and HP 5065A
Corby Dawson wrote: Hi, I'm curious what year was the last year that HP offered the 5065A for sale and what the list price was for that year. It is in the 1993,94,95, or 96 catalog. Can any one who has one of these years catalogs check and see? OK Corby, it is NOT in the 1993 or later catalogs. I see it in 1991 offered for $36,200 for the base model, but can't find 1992. Maybe someone has that one, or there is a site with a lot of them on line as pdfs. That narrows it down a bit! Dan ___ time-nuts mailing 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] Splitting GPS antenna output
Keep an eye open at swap meets etc., or even eBay, for something like an MCL ZAPD-2, http://www.minicircuits.com/pdfs/ZAPD-2+.pdf which is a 1 to 2 GHz splitter. It has DC continuity from 1 and 2 to the common. I put a 100 pF blocking cap in one of the ports, the other feeds DC to the antenna. An R and choke could be fitted if the receiver connected to the isolated port complains. I used one of these for years when I only had two gps units; now a lucky find of one of the 8 way -hp- splitters serves me well, and still has one or two empty ports... -hp- did make a four way one but not I think, a two way. Incidentally these things and similar are very useful just as boxes with SMA sockets, for the usual $1 or so they fetch at swap meets, they are well worth grabbing. Dan ___ time-nuts mailing 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] Racal 2201 Frequency Counter
gandal...@aol.com wrote: Following recent discussions about the merits, or otherwise, of the Racal 1991/92 counters, is anybody familiar with the 225MHz two channel 2201 which was marketed as being the 1991 replacement? With an optional 1.3GHz third channel fitted it was also offered as the replacement for the 1992. Nigel, the 1992 with Hi Stab Oven option was bought in /very/ large numbers by the US military, hence the relative popularity of that one over the 1991, 1998 and later models over here. I have never even seen the one you refer to :^) Even the 1992 duff button problem was solved by some kind soul who was selling bags of 100 replacements on eBay recently for a very good price, enough for three 1992s. With all the counters I have here it is the 1992 that stays on the bench, the -hp- ones sit in the garage. Dan ___ time-nuts mailing 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] HP 5065A Manual
Brian Kirby wrote: I purchased a original HP 5065A manual and scanned it. The pictures, oscilloscope pictures and some of the schematics were greyscaled to bring out the details. Its available at http://www.kennethkuhn.com/hpmuseum/scans/ Its in three parts, each part being around 10 mb. Brian - KD4FM Thanks for doing this Brian. I see it also has the updates for the later 1980s versions using the 10811 Oven which have proved so elusive in the past. Dan ___ time-nuts mailing 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] HP 5065A Manual
Funnily enough none of the Update changes that I have found specifically refer to my Serial Prefix, 2432, but I think I'm covered anyway :^) Thanks again for the effort Brian, Dan ___ time-nuts mailing 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] Dual Mixer
ewkeh...@aol.com wrote: As part of the Dual Mixer project I am looking for a source of reasonably priced 80 MHz Xtal's in HC 49 holder. International Crystal wants $12 in fifty Qty. In my opinion to high. Any help will be appreciated. Thanks Bert Kehren How about XC1567CT-ND from Digikey, around $5 each? http://www.ecsxtal.com/store/pdf/ecx-2236.pdf Dan ___ time-nuts mailing 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 demise
Mark Spencer wrote: Yep... There is some room for experimenation. As an example looking at some of the results reported from the ARRL Frequency measuring test, it seems that some of the participants are able to determine the frequencies of HF signals progated via sky waves with an accuracy considerably better (maybe two orders of magnitude ?) than common literature would suggest is possible.Something to do when I retire (: The last time I did it, in 2003, I got to within 0.1 Hz ( in California) by dint of averaging by eye and no computer in use, the total variation was about 1 Hz on 20 meters. Some sort of computerized logging would have achieved the same result I'm sure. Looking at WWV here one sees a similar picture, up to one cycle of phase shift at 10 MHz, depending a lot on the time of day. Given that many amateurs now have frequency standards several orders of magnitude better than this any FMT that is not line of sight becomes mainly an exercise in logging and averaging. Dan ac6ao / g3ncr ___ time-nuts mailing 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] Sparkfun
There has to be a better way to get a prologix. An hour to get to the page to order it and now I cannot proceed to the check out section at all. Ridiculous! There is indeed no such thing as a free lunch or a cheap GPIB adapter :^) Dan ___ time-nuts mailing 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] Sparkfun
F1ETB wrote: Good Advertisement for a company in Electronics... Happy New Year to everyone, Bernard I don't know Bernard. Having just wasted an hour plus of my life on it I don't think I will return there again. Dan ___ time-nuts mailing 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] Accurate Position
I just found out that Google Earth now gives a seemingly quite accurate position at the mouse pointer which I don't remember seeing before. This would seem like a good way to start for a T-bolt survey for example. Dan ___ time-nuts mailing 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] HP 58516A GPS distribution amplifier information
Bob Camp wrote: Hi Has anybody torn into one to see how easy/hard that would be? Sometimes HP's construction techniques are not very hacker friendly.. Bob, I had to do that because my 8 way version came from the swap meet fried ( it was only $5). The circuitry inside is very obvious since it is all surface mount. Since you probably will have multiple GPS's on the gizmo (why have it otherwise...) Leaving the 200 ohm DC resistors in place does not sound like a problem. Maybe you short out two of the DC blocks rather than just one. Converting it to be powered from the No 1 output is easy, but you do NOT want to try to power the antenna from two outputs. Unless you want a schizoid divider. Dan ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
