Re: [time-nuts] homebrew maser

On Tue, 31 Aug 2010 17:02:16 -0700 John Miles jmi...@pop.net wrote: Microwave test gear and plumbing is very significantly harder to get at 24 GHz than at 1.4 GHz. At a guess I've seen easily 100 times more stuff available at 1.4 GHz. That is so far down the list of 101 Things That

Re: [time-nuts] homebrew maser

time and frequency measurement Subject: Re: [time-nuts] homebrew maser How about a Laser-Cooled Mercury Ion Frequency Standard? http://tf.nist.gov/general/pdf/1225.pdf Here's another approach: A diode-laser optical frequency standard based on laser-cooled Ca atoms:Sub-kilohertz spectroscopy

Re: [time-nuts] homebrew maser

On 09/01/2010 04:11 AM, Heathkid wrote: How about a Laser-Cooled Mercury Ion Frequency Standard? http://tf.nist.gov/general/pdf/1225.pdf I have way too little liquid helium dewar flasks at all... but sure, it would be fun. I would certainly see a bunch of challenges in mixing down from about

Re: [time-nuts] homebrew maser

To: time-nuts@febo.com Sent: Wednesday, September 01, 2010 2:51 PM Subject: Re: [time-nuts] homebrew maser On 09/01/2010 04:11 AM, Heathkid wrote: How about a Laser-Cooled Mercury Ion Frequency Standard? http://tf.nist.gov/general/pdf/1225.pdf I have way too little liquid helium dewar flasks

[time-nuts] homebrew maser

Attila, The precision on the cavity itself does not need to be so tight as a mechanical tuning plunger takes up the initial tuning slack. The varactor tuning covers more than 10Khz This cavity is held at approx. 50 degrees C. The collimator for an active maser is a bundle of MANY hollow glass

Re: [time-nuts] homebrew maser

Corby, Do you know if the collimator is made from an uncoated microchannel plate? If so, an old, broken Gen II image intensifier might be a viable source. Best, -John Attila, The precision on the cavity itself does not need to be so tight as a mechanical tuning plunger takes

[time-nuts] homebrew maser

Same general idea,  but an image intensifier plate would probably not work well.  They are usually thinner and are cut at a bias so the electrons ricochet along its length.  You might be able to mount one so that it cancels the bias angle. They are made by stretching a bundle of hollow glass

Re: [time-nuts] homebrew maser

PTFE wall storage bulb wall coatings haven't been used for some decades, FEP (or the Russian fluoropolymer ) is better in that a smoother coat is achievable see: http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2doc=GetTRDoc.pdfAD=ADA509340

Re: [time-nuts] homebrew maser

...@febo.com [mailto:time-nuts-boun...@febo.com]on Behalf Of Bruce Griffiths Sent: Tuesday, August 31, 2010 1:23 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] homebrew maser PTFE wall storage bulb wall coatings haven't been used for some decades, FEP

Re: [time-nuts] homebrew maser

Griffiths Sent: Tuesday, August 31, 2010 1:23 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] homebrew maser PTFE wall storage bulb wall coatings haven't been used for some decades, FEP (or the Russian fluoropolymer ) is better in that a smoother coat

Re: [time-nuts] homebrew maser

Microwave test gear and plumbing is very significantly harder to get at 24 GHz than at 1.4 GHz. At a guess I've seen easily 100 times more stuff available at 1.4 GHz. That is so far down the list of 101 Things That Are Hard About Building a Hydrogen Maser I'm not even sure it makes the top

Re: [time-nuts] homebrew maser

?pub_id=105042 - Original Message - From: John Miles jmi...@pop.net To: j...@quik.com; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Tuesday, August 31, 2010 8:02 PM Subject: Re: [time-nuts] homebrew maser Microwave test gear and plumbing is very

Re: [time-nuts] homebrew maser

: [time-nuts] homebrew maser Microwave test gear and plumbing is very significantly harder to get at 24 GHz than at 1.4 GHz. At a guess I've seen easily 100 times more stuff available at 1.4 GHz. That is so far down the list of 101 Things That Are Hard About Building a Hydrogen Maser

[time-nuts] Homebrew Maser

John, Initial tuning is not the bugaboo. It's fairly easy to set the frequency with a synthesizer as a probe into the cavity via the circulator. Once within 10Khz or so you then pick up the difference with the cavity temp. You adjust so that the cavity is set within the varactor tuning range.