Well, I already have a 3458A, a 34420A, a GPSDO (with 10Mhz output), and so all I need is something that produces a fixed 10V (and 1V would be OK too). I was thinking of something like the "Compact Josephson Junction Array" [CJJA] that is used for inter-comparisons, etc. This unit has an SIS array, and is very "finicky" to get working-- so something based on a SINIS array (highly damped) or something similar that can be used without having a PhD... It is already understood that NIST has the best solution for this if you want the "Cadillac" version, (and have virtually unlimited funds)-- but I don't have unlimited funds, and I don't need a programmable output, and I don't need to generate AC waveform, and I don't need or want all of the complexity. $400K is *WAY* out of my budget. I was looking more for something on the surplus market-- or some "cast away" JJA that someone is getting ready to throw into the dumpster-- something that nobody wants anymore that I can get working on a _very_limited_ budget... That's why I mentioned the CJJA, because that has the RF source and everything built-in (well, except for the programmable current source, but I can build those all day long in my sleep). -Ken

On 19 October 2016 at 20:15, Ken Peek <ken.peek@diligentminds.com> wrote: > Well, I already have a 3458A, OK, quite an expensive multimeter. Otuside my budget for something I don't really need, but would like! $400K is *WAY* out of my budget. I was looking more for > something on the surplus market-- or some "cast away" JJA that someone is > getting ready to throw into the dumpster-- something that nobody wants > anymore that I can get working on a _very_limited_ budget... It might be worth mentioning how much money you are willing to spend on it, as it may give people ideas about what could possibly be done yourself, and what is just not going to be practical. You may well find getting liquid helium impossible. Here in the UK it is very difficult to get chemicals dangerous chemical if you are not on an industrial site. I very much doubt British Oxygen Company (BOC) would delivery liquid helium to my house. Stage 1 would be to see what you would need in order to get the He delivered. Without that you are not going to get anywhere, and I doubt you will get that delivered unless you have vessels that have been properly maintained. I would imagine that just getting the stuff delivered would be next to impossible without spending a lot of money, especially in the USA.

$400K is *WAY* out of my budget.  I was looking more for

Hello Ken, you can also buy it here: http://www.supracon.com/en/dc_josephson_voltage_standard.html there is also a version with cyro cooler so no need to handle with dangerous liquids. With best regards Andreas Am 19.10.2016 um 22:56 schrieb Dr. David Kirkby (Kirkby Microwave Ltd): > On 19 October 2016 at 20:15, Ken Peek <ken.peek@diligentminds.com> wrote: > >> Well, I already have a 3458A, > > OK, quite an expensive multimeter. Otuside my budget for something I don't > really need, but would like! > > > $400K is *WAY* out of my budget. I was looking more for >> something on the surplus market-- or some "cast away" JJA that someone is >> getting ready to throw into the dumpster-- something that nobody wants >> anymore that I can get working on a _very_limited_ budget... > > It might be worth mentioning how much money you are willing to spend on it, > as it may give people ideas about what could possibly be done yourself, and > what is just not going to be practical. > > You may well find getting liquid helium impossible. Here in the UK it is > very difficult to get chemicals dangerous chemical if you are not on an > industrial site. I very much doubt British Oxygen Company (BOC) would > delivery liquid helium to my house. > > > Stage 1 would be to see what you would need in order to get the He > delivered. Without that you are not going to get anywhere, and I doubt you > will get that delivered unless you have vessels that have been properly > maintained. > > I would imagine that just getting the stuff delivered would be next to > impossible without spending a lot of money, especially in the USA. > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there.

		Attila Kinali

On Wed, 19 Oct 2016 12:15:56 -0700 Ken Peek <ken.peek@diligentminds.com> wrote: > Well, I already have a 3458A, a 34420A, a GPSDO (with 10Mhz output), and so > all I need is something that produces a fixed 10V (and 1V would be OK too). > > I was thinking of something like the "Compact Josephson Junction Array" > [CJJA] that is used for inter-comparisons, etc. This unit has an SIS > array, and is very "finicky" to get working-- so something based on a SINIS > array (highly damped) or something similar that can be used without having > a PhD... > > It is already understood that NIST has the best solution for this if you > want the "Cadillac" version, (and have virtually unlimited funds)-- but I > don't have unlimited funds, and I don't need a programmable output, and I > don't need to generate AC waveform, and I don't need or want all of the > complexity. $400K is *WAY* out of my budget. I was looking more for > something on the surplus market-- or some "cast away" JJA that someone is > getting ready to throw into the dumpster-- something that nobody wants > anymore that I can get working on a _very_limited_ budget... That's why I > mentioned the CJJA, because that has the RF source and everything built-in > (well, except for the programmable current source, but I can build those > all day long in my sleep). Uhmm.. you are aware that any Josephson junction based system requires cryogenic temperatures. Even the "high temperature" JJA still need liquid helium, which is, as other have said, nothing that you can just buy. Even the gear you need to keep liquid helium costs several 10k at least on the surplus market... if you can get your hands on that stuff anyways (that's lab equipment and lab equipment is usually used until it breaks and cannot be repaired anymore). Even the microwave gear will cost you at least a couple of thousand. If you want to get an idea how much gear you need to run a JJA, have a look at page 30 of [1]. But don't worry, none of these systems need a PhD to use. Even though the theory behind them is quite complicated and involves some heavy math and physics, their use is pretty straight forward (at least for a quantum physical system). Attila Kinali [1] http://www.wmi.badw.de/teaching/Lecturenotes/AS/AS2013_Chapter6_Slides.pdf -- Malek's Law: Any simple idea will be worded in the most complicated way.