Rubidium frequency standard Extreme Teardown

[ForViewingOnly]

Excellent video Mike, really interesting. Do be careful with that Dremel though, I know how fingers work and don't want to see a cross section of them ;-)

[mikeselectricstuff]

@ForViewingOnly Grinding wheels don't cut soft materials like flesh very well - the biggest risk is shrapnel from the wheel breaking.

[MrGerbilBrain]

aw, you should have popped the shorted circuitboard! D:

[narcoti]

What dremel tool are you using?

[mikeselectricstuff]

@narcoti Proxxon mains drill with a thin cutting disk.

[Films4You]

5:43 Watch out for you thumb / fingers. 6:01 Pliers Good...

I want you to make more Great video's like this but not be injured

[douro20]

It's interesting that they would use N-channel MOSFETs in that manner...

[EEVblog]

Excellent follow-up. thanks Mike!

[zaprodk]

Cool that you did tear it down completely! - Great seeing how this black magic works

[CampKohler]

Should any gas lamp similarly excited externally (vs. via electrodes) "last forever" on the theory that the electrodes aren't being used to interface energy with the gas and so nothing should deteriorate?

[amfan12]

@CampKohler In theory, yes. However in practice, the gas charge/metal in the lamp will end up slowly diffusing into the glass.

[CampKohler]

I put a link to here in a reply on Dave's vlog.

[TheCrazyInventor]

Thank you for continuing where Dave left off. Interesting to see all that "weird alien evil RF black magic" technology in there. :) Some funky engineering going on in that device.

[nik282000]

Not many people have said "Oh well, need more rubidium." You just joined a very elite club.

[SigEpBlue]

"Need more rubidium...." XD

It's amazing how...prototype-y(?)...the device appears, with all of the components stuck right on the cases -- that or I'm just not used to seeing that type of assembly. It's almost hard to believe those were mass-produced in that form, but I'm sure like anything else, they've got the process down to an economical science. :)

Many thanks for tearing it apart and showing us!

[mikeselectricstuff]

@SigEpBlue "Mass-produced" for this sort of thing is probably only a few thousand... remember these things would have originally cost over a grand, so a minute or two on the production line to hand-solder some wires isn't a biig deal. The high operating temperatures limit the choice of mounting methods available.

[008626]

The RF excited bulb and the cavity components were very interesting, thanks for the teardown

[kibi15]

Lucky for us you got a duff unit to conduct an extreme teardown on.

Thanks very much. I'd been wondering what exactly is inside the "physics package" since Dave did his teardown.

Cheers

[coondogtheman1234]

so what is this thing and what's it used for?

[CampKohler]

@coondogtheman1234 It is an oscillator that produces a signal whose exact frequency is determined by the physical characteristics of rubidium gas; it's super accurate and stable and is therefore a "frequency standard." At high cost, they were used to govern the operation of cellular phone sites; as low cost surplus, we can be feed them into measuring instruments to allow them to take on the same accuracy and stability.

It will NOT make pizza taste better or attract girls (or vice versa).

[coondogtheman1234]

@CampKohler

LOL!

I figured it had something to do with radio waves but I wasnt sure if it was used for a radio station or not. Thanks for the info.

[Mikkel324]

Sorry for the multiple comments, they are limited in length so I have to split them up. I think two cells serve different purposes. The one closest to the lamp should be a filter and the one closest to the photocell should be the resonance cell. If I recall correctly they contain different rubidium isotopes, the filter contains rubidium 85 and the resonance cell contains rubidium 87. The lamp contains either pure Rb87 or a mixture.

[Mikkel324]

I forgot to mention, I think the coil inside the physics package shield is for the c-field which is for fine-tuning of the frequency. I'm not sure this feature is used here though, as the DDS can be tuned in extremely fine steps.

[Mikkel324]

If you let the rubidium lamp heat up and then lower the supply voltage, the glow of the fill gas (argon?) will extinguish and you will see the spectral light from the rubidium. An incredible deep purple glow.

[JumperOneTV]

Thank you! Very interesting stuff.

[Kankki1]

@JumperOneTV When are you gonna start making videos again, dude? :D

[JumperOneTV]

@Kankki1 I'll put out new video this Fri. or Sat.

[Kankki1]

@JumperOneTV Awesome :D Your vids are awesome, and when I saw your comment I just had to ask :)

[JumperOneTV]

@Kankki1 yeah, it's time to get back on track :)

[ciprianwiner]

Nice job :D

[antadefector]

Just a thought, maybe the cavity resonant frequency is fine tuned by magnetic field. Long time ago, my friend from military showed me some microwave constructions (he called it Ig filter) which is current controlled filter.... I'm trying to find something resembling it on google but with no luck soo far. If I find something I will post....

Best Regards,

Goran

[Kilohercas]

@antadefector

as i sad before,

SRF Superconducting_Radio_Frequenc­y , well, it same thing, just not so conductive :)

[sbreheny]

@antadefector I think you mean a "YIG" filter. YIG = Yttrium Iron Garnet - a type of dielectric material whose resonant frequency (for a given shape) depends on the external DC magnetic field. They use a tiny (about 1mm diameter) sphere of this material inside the filter and then couple RF into and out of it. A simple metal cavity resonator doesn't change its resonant freq because of DC magnetic field. The Rb hyperfine freq does depend on the external mag field, though.

[antadefector]

@sbreheny I would't go any deeper into analyzing since it was about 15 (17) years ago, and I knew much less then now (not that I know much now). English, not being a natural language, is not so fluent to me that I'm able to explain in great detail with few words.

Had found something that looks like, but its not. I'm sure it's what You say it is, and @Kilohercas too.

[pieznice29]

"RF black magic" "Alien microwave technology" Brilliant.

I'm tempted to get one of these rubidium standard sources since they are so cheap. The electrodeless lamp interests me the most, might just get one to play around with that...

[Kilohercas]

screw can regulate resonant frequency of the cavity, it's called cavity resonator.

it should be very high quality resonator

[Kilohercas]

excellent, i was waiting for this tear-down of physics package