Has anyone attempted to build a maser before?

[mfo]

What the title says. I'm sure it's not the brightest of ideas for the average person, but I'm sure it would be cool if you could do it with all of the safety precautions in place. So, has anyone built/seen one?

 

[suiraM]

Building one would be a major feat, I think.

Really, making any kind of maser is expensive and difficult.

A ready made hydrogen maser unit will sell for a quarter million or so. As far as I know, there is only one person that owns his own hydrogen maser (actually, five of them), in the form of hydrogen maser atomic clocks. These atomic clocks are precise to better than a femtosecond per year, which is rather impressive.

What kind of experience do you have with DIY gas lasers?

 

[mfo]

What kind of experience do you have with DIY gas lasers?

Absolutely none. What you said was interesting though.

 

[suiraM]

Start out with a Nitrogen TEA gas laser. Get the goggles first, as 337nm is going to leave scars on your eyeball if it hits you. Then move on to pure nitrogen transverse excitation types, carbon dioxide and helium-neon. Look up Venturi pumps to save a bit of money at this point. Then move on to pulsed oxygen, copper vapor, iodine and so forth.

At some point, you will either stop, or move on to the maser, or decide that you would rather use the skills you acquired in building your own linear accelerator and then move on to a synchrotron instead. Then you're screwed, and hopefully loving it. Then your wife, or the FCC, whichever finds out first, will put a stop to it. Either way, the maser remains a long shot.

 

[HIMNL9]

Uhm ..... a MASER is based on microwaves (Microwave Amplification by Stimulated Emission of Radiation) ..... and i know microwaves enough to not want to play around them in high power beams form (not without a complete shielded suit, at least )

Still i have to have around an old klystron from a microwave oven, but it's sitting somewhere collecting dust from a lot of years ..... never decided to hook it up and play with it, til now

 

[mfo]

Start out with a Nitrogen TEA gas laser. Get the goggles first, as 337nm is going to leave scars on your eyeball if it hits you. Then move on to pure nitrogen transverse excitation types, carbon dioxide and helium-neon. Look up Venturi pumps to save a bit of money at this point. Then move on to pulsed oxygen, copper vapor, iodine and so forth.

At some point, you will either stop, or move on to the maser, or decide that you would rather use the skills you acquired in building your own linear accelerator and then move on to a synchrotron instead. Then you're screwed, and hopefully loving it. Then your wife, or the FCC, whichever finds out first, will put a stop to it. Either way, the maser remains a long shot.

Haha, very nicely put.

Uhm ..... a MASER is based on microwaves (Microwave Amplification by Stimulated Emission of Radiation) ..... and i know microwaves enough to not want to play around them in high power beams form (not without a complete shielded suit, at least )

Still i have to have around an old klystron from a microwave oven, but it's sitting somewhere collecting dust from a lot of years ..... never decided to hook it up and play with it, til now

Glad I've inspired you!

 

[digital_blue]

Still i have to have around an old klystron from a microwave oven, but it's sitting somewhere collecting dust from a lot of years ...../QUOTE]

Do you mean magnetron? IIRC a klystron is a special type of vacuum tube used to amplify microwaves...

 

[HIMNL9]

Do you mean magnetron? IIRC a klystron is a special type of vacuum tube used to amplify microwaves...

Wait, wait, i'm making confusion with the names, as usual .....

i have two microwave emitters from my militar times (new sealed units, that in the army become trashed after the usage date, also if they are still on a shelf, and when we had to throw away them, i saved a pair for my collection ), that looks like this one, just with a rectangular flange, and these are klystron

then have one like this, and another similar, but round, both come from old mangled microwave ovens (and probably one is burned, but never tried to hook up them), and these ones are magnetrons, you're right, my mistake ..... thanks.

 

[digital_blue]

Is that klystron made by varian? If so, those are worth quite a bit of money($1300USD or so).

 

[suiraM]

Unlike a hydrogen maser, a klystron actually has a real, high power output.

A hydrogen maser puts out picowatts.

A klystron can put out from a few watts to several megawatts, depending on type.

 

[Hemlock_Mike]

I have one of those Varian Klystrons --- VA220C ----
I never knew how to test it but it looks like the above picture.
Mine appears to have a fillament too !!
HMike

 

[HIMNL9]

Yes, these ones are Varian units ..... the only difference with the one in the pic (pic is not mine), is that my ones have a rectangular flange, instead a round one like this, where the ceramic window cover the output, cause they was produced for fit the wave guides in military apparates (under the army, i worked for some months in the lab where we made maintenance on these and other units)

The "funny" thing was that, as army rules, any single piece had its own "expiration date", regardless from the fact that you used it or not ..... each month, we had to throw away the units and parts that had expired date, and substitute them also if for all the time they was just sitting on a shelf ..... i throwed away so much brand new, still sealed things, too big for take them at home, that sometimes i almost cried .....

 

[Benm]

..... and i know microwaves enough to not want to play around them in high power beams form (not without a complete shielded suit, at least )

What makes you affraid of microwaves? They arent more dangerous than light at equal power levels, and usually not that easy to focus on a small area due to the larger wavelength.

As long as you stay within the couple-of-watts range the danger is limited, unless you would decide to have a look into an output coupler of a running system or something crazy like that. With DIY is in the high operating voltages.

One thing to avoid especially is mucking with microwave oven parts - a few kilowatts of supply power at a couple of kilovolts will readily kill you when you get your hands in the wrong place.

At this power level the output from the waveguide still is not crazily dangerous from a bit of distance. I wouldn't suggest you put your hand in front of it, but from a few feet away you could feel the heat, at best.

 

[HIMNL9]

^ @ Benm: Don't know ..... i feel myself safe with high voltages, with high power lasers, also with high explosives, but not with microwaves ..... maybe it's not logic, it's just a personal feeling.

 

[Hemlock_Mike]

Why should a klystron "expire" unused? Is the cathode thorium coated with short half life? It's just a tuned cavity tube.

HMike

 

[digital_blue]

Why should a klystron "expire" unused? Is the cathode thorium coated with short half life? It's just a tuned cavity tube.

HMike

A klystron is similar to vacuum tubes; the less you run it, the more air will leach inside. This can cause premature filament failure or(in some cases) catastrophic failure of the tube. If you want to keep that klystron in working condition, you should probably run it once a year.