Re: [time-nuts] [EXTERNAL EMAIL] Sayrosa 607B Frequency Synthesiser
Hi Nigel, It will also be the first info on the 607B that I have ever seen I will certainly download it when I get home (work filtering forbids it, with much else). Should allow me to fish my one out of the attic and actually use it - after letting the magic smoke out of the tants, of course :-) Many thanks, in advance, for your efforts. Regards, Paul,G8GJA -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of gandalfg8--- via time-nuts Sent: 10 June 2018 20:31 To: time-nuts@febo.com Subject: [EXTERNAL EMAIL] [time-nuts] Sayrosa 607B Frequency Synthesiser Perhaps not a very common item, and probably restricted to the UK, but I have seen these mentioned here before. The 607B was a very nice 2 to 30MHz synthesiser used as the drive unit in the UK Diplomatic Service Piccolo radio system. Both Sayrosa and Piccolo are long gone, and information has always been hard to come by, but I've just scanned the 607B Training Manual and 607B Technical Handbook and uploaded PDF versions of both to Mediafire. This documentation is quite limited but so far is all I've ever seen for the 607B. Both can be found in a single file at http://www.mediafire.com/file/c6vv5t71cq741sd/Sayrosa%20607B.zip For what it's worth, my experience with these has been that by far the most common fault is the familiar shorted tantalum syndrome. Nigel GM8PZR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] ?==?utf-8?q? a newbie question: where can I purchase 794.7 nm VCSEL for building CPT rubidium clock?
One might then ask what the availability and pricetag is for nonlinear chrystal needed for frequency doubling. If it is esoteric enough to get and priced similar, well then the gain is lost. Cheers, Magnus On 06/07/2018 09:18 PM, Henk Peek wrote: > Rb vapor-cell clock demonstration with a frequency-doubled telecom laser > > Applied Optics Vol. 57, Issue 16, pp. 4707-4713 (2018) > •https://doi.org/10.1364/AO.57.004707 > > Abstract > > We employ a recently developed laser system, based on a low-noise telecom > laser emitting around 1.56 μm, to evaluate its impact on the performance of > an Rb vapor-cell clock in a continuous-wave double-resonance scheme. The > achieved short-term clock instability below 2.5·10−13·𝜏−1/2 demonstrates, for > the first time, the suitability of a frequency-doubled telecom laser for this > specific application. We measure and study quantitatively the impact of laser > amplitude and frequency noises and of the ac Stark shift, which limit the > clock frequency stability on short timescales. We also report on the detailed > noise budgets and demonstrate experimentally that, under certain conditions, > the short-term stability of the clock operated with the low-noise telecom > laser is improved by a factor of three compared to clock operation using the > direct 780-nm laser. > > © 2018 Optical Society of America under the terms of the OSA Open Access > Publishing Agreement > > Henk Peek > > On Tuesday, June 5, 2018 11:11 CEST, Attila Kinali wrote: > >> On Mon, 4 Jun 2018 21:31:56 +0800 >> mimitech mimitech wrote: >> >>> I'm planning to build a CPT (coherent-population-trapping) rubidium clock >>> as my next hobby project. The main purpose is to learn the principles >>> behind CPT rubidium clock, and hopefully got similar or better performance >>> than commercial miniature rubidium clock such as FE-5680A. >> >> Building a CPT clock is slightly more involved than you might think >> at first. The laser diode is only one part of it. You will most likely >> be able to improve on the short-term stability of the FE-5680 (which >> is rather poor). But I doubt you will be able to improve much on >> the long term stability, which is where things actually become interesting, >> if you use a naive approach. >> >> Nevertheless, I have not seen many 794/795nm diodes around. The only >> one that I have the datasheet of is the one from Vixar. >> You might want want to consider going for the D2 line instead of the >> D1 line, as 780nm diodes are more commonly available than 795nm. You will >> also need to buy several of those and select the ones that come closest >> to the wavelength at the desired opearating conditions (usuall spread >> is +/-1nm to +/-10nm). Do not assume you can tune more than 0.1nm with >> temperature and current (rule of thumb is that you get about 10GHz >> per °C and mA). If you need more tuning range, you will need to add an >> external cavity (can give you up to 5nm range), which then needs to be >> tuned to the 3.45GHz (ie it's length needs to be approximately 8-9cm). >> >> Alternatively, you can get two S1-0780-XXX from Sacher Laser >> (cost IIRC 2500€ each) and keep them 6.9GHz apart (using an optical PLL). >> If you have enough money to spend, I'd go for two Cateye diode laser CEL's >> from Moglabs (cost AFAIK 5000€ each) >> >> No matter what you choose, you will need some wavelength stabilization >> scheme. You can either do that with the vapor cell itself or use >> an additional cell and do a DVALL or a saturated absorption locking. >> Note that this addtional cell will need to be without buffer gas. >> An external cell will offer better stability and thus lower noise, >> which directly translates into higher stability. >> >> As polarisation scheme, I suggest using σ+/σ- as it seems to be more >> robust than the lin/lin schemes. >> >> Attila Kinali >> -- >> It is upon moral qualities that a society is ultimately founded. All >> the prosperity and technological sophistication in the world is of no >> use without that foundation. >> -- Miss Matheson, The Diamond Age, Neil Stephenson >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > > > > ___ > time-nuts mailing 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] 2 X R-388's W/non-original cases for sale
Hi List, Besides a four sail ad, it's a bit of a bottom feeder story. Several weeks ago, I made a post of 3 R-338's for sale. One was missing the S-meter so I listed it a *parts unit*. I also stated that FedEx shipping based on my experience for the units with cases would be in the $125 range each. The next day I get a long distance call from X who lives in XX, a state far, far away from CA. Who wanted to buy both R-388's with cases. He askes me *Am I near a military base?* No, I reply curiously asking why he asked? Well he was retired militay he vagely implied a had some special shipping araignment available. He then asks *Do I know of a freight shipping place nearby?* I reply that I have no idea, but I curiously ask why? His relpy was that they *could be strapped to a palate for cheap shipping.* Next he asks if * I would hold the radios for 24 hours while he checked shipping prices?* Sure, No Problemo. So the next or so I get an email stating that the cheapest shipping that he could find was $225 and *these were PARTS radios and he coluld get an estate R-388 for IIRC $250.* I took that to mean he felt my prices were too high. Now I don't know how he missed the part whereI had said that the radios came with IREC tube shields and a case, but were complete. Now any radio with *Bathtub* cap need to have them replaced because of high ESR being 60 years old. It has been well reported by Bill Orr and others that the resistor network in the HV that's used to create negative bias chages value resulting in poor performance. So I still have 2 X R-388's for sale that have IREC tube shields, are in non-OEM cases, have bath tub and a electrolytic filter cap that should be repla retired as it is OEM. So the price is still $125 each plus a larger shipping price due to the weight of case. Estimate $100+ (Do an original email please) If one can find a better deal, please but it and inform the list so we all can be envious. Like the guys who got WWII surplus jeeps for $50 in long past times. Regards, Perrier ___ time-nuts mailing 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] Sayrosa 607B Frequency Synthesiser
SayRosa may be long gone but a lot of their IP went over to Wayne Kerr and some is still produced to this day, the 257 automatic modulation meter is one I think. On Sun, 10 Jun 2018 at 20:31, gandalfg8--- via time-nuts wrote: > Perhaps not a very common item, and probably restricted to the UK, but I > have seen these mentioned here before. > > The 607B was a very nice 2 to 30MHz synthesiser used as the drive unit in > the UK Diplomatic Service Piccolo radio system. > > Both Sayrosa and Piccolo are long gone, and information has always been > hard to come by, but I've just scanned the 607B Training Manual and 607B > Technical Handbook and uploaded PDF versions of both to Mediafire. > > This documentation is quite limited but so far is all I've ever seen for > the 607B. > > Both can be found in a single file at > > http://www.mediafire.com/file/c6vv5t71cq741sd/Sayrosa%20607B.zip > > For what it's worth, my experience with these has been that by far the > most common fault is the familiar shorted tantalum syndrome. > > Nigel GM8PZR > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Clint. M0UAW IO83 *No trees were harmed in the sending of this mail. However, a large number of electrons were greatly inconvenienced.* ___ time-nuts mailing 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] Sayrosa 607B Frequency Synthesiser
Perhaps not a very common item, and probably restricted to the UK, but I have seen these mentioned here before. The 607B was a very nice 2 to 30MHz synthesiser used as the drive unit in the UK Diplomatic Service Piccolo radio system. Both Sayrosa and Piccolo are long gone, and information has always been hard to come by, but I've just scanned the 607B Training Manual and 607B Technical Handbook and uploaded PDF versions of both to Mediafire. This documentation is quite limited but so far is all I've ever seen for the 607B. Both can be found in a single file at http://www.mediafire.com/file/c6vv5t71cq741sd/Sayrosa%20607B.zip For what it's worth, my experience with these has been that by far the most common fault is the familiar shorted tantalum syndrome. Nigel GM8PZR ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Inside a dead Lucent 40 db cone
https://photos.app.goo.gl/oDjphd6DQhyrQp1w7 ___ time-nuts mailing 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] HP5065C or the 5065Jr.
Very Nice!! What is mounted on top of the 10811? Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of cdel...@juno.com Sent: Saturday, June 09, 2018 4:58 PM To: time-nuts@febo.com Subject: [time-nuts] HP5065C or the 5065Jr. Hi, Thought I'd share some PIX of an HP5065A I made up from spare parts. Chassis was from an HP8620C and there is no AC supply, it runs off of external +24VDC. Unit has 5 and 10 Mhz outputs. It tests well and easily exceeds the HP specs. Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP5065C or the 5065Jr.
nicely done ! On Sun, Jun 10, 2018 at 8:53 AM wrote: > Hi, > > Thought I'd share some PIX of an HP5065A I made up from spare parts. > > Chassis was from an HP8620C and there is no AC supply, it runs off of > external +24VDC. > > Unit has 5 and 10 Mhz outputs. > > It tests well and easily exceeds the HP specs. > > Cheers, > > Corby___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
