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How to select transistor for oscillator ?

Started by Unknown September 11, 2018
John Larkin wrote
>Does anybody know what this is? > >https://www.dropbox.com/s/np4s7ifgg5f4gbz/DSC01841.JPG?raw=1 > >https://www.dropbox.com/s/6ckipx3z8v4nf72/DSC01844.JPG?raw=1 > >Spark gap? Waveguide T/R switch?
It is probably one of those fortune telling machines that you have to rotate and then you see the future in it. google does not know that number, you should tell them.
> > CK722 was slow, maybe under 1 MHz, but the data sheets didn't spec it. > I think it was a nasty alloy-junction part. > >
2N107 my first transistor m
On Thu, 13 Sep 2018 15:02:14 GMT, <698839253X6D445TD@nospam.org>
wrote:

>John Larkin wrote >>Does anybody know what this is? >> >>https://www.dropbox.com/s/np4s7ifgg5f4gbz/DSC01841.JPG?raw=1 >> >>https://www.dropbox.com/s/6ckipx3z8v4nf72/DSC01844.JPG?raw=1 >> >>Spark gap? Waveguide T/R switch? > >It is probably one of those fortune telling machines that you have to rotate and then you see the future in it. >google does not know that number, you should tell them.
OK, you don't know. -- John Larkin Highland Technology, Inc lunatic fringe electronics
<698839253X6D445TD@nospam.org> wrote in
news:pndu81$1l3q$1@gioia.aioe.org: 

> John Larkin wrote >>Does anybody know what this is? >> >>https://www.dropbox.com/s/np4s7ifgg5f4gbz/DSC01841.JPG?raw=1 >> >>https://www.dropbox.com/s/6ckipx3z8v4nf72/DSC01844.JPG?raw=1 >> >>Spark gap? Waveguide T/R switch? > > It is probably one of those fortune telling machines that you have to > rotate and then you see the future in it. google does not know that > number, you should tell them. >
It is either a diode vacuum tube or a vacuum tube triode. Used in transmitter output sections.
>John Larkin wrote >>>>>>But most CCROs are probably used as >>>>>>bandpass filters. >>>>>> >>>>>>http://www.mpdigest.com/2017/01/23/ceramic-resonator-band-pass-filter/ >>>>> >>>>> >>>>> >>>>>Yes of course, those ceramic filters, or should I say SAW filters, are everywhere, >>>>>for example in TVs as IF filter. >>> >>>>A CCRO is different from a SAW. And different from a mechanically >>>>resonant ceramic filter. I guess you knew that.
What you probably meant by CCRO is a dielectric resonator based oscillator https://en.wikipedia.org/wiki/Dielectric_resonator The link you pointed to says ceramic-resonator-band-pass-filter CCRO filter stands for Closed Circuit Reverse Osmosis filter something entirely different. Yes dielectric resonators are the same as the 'pucks' in the picture I showed earlier: http://panteltje.com/pub/5_dollar_LNB_PCB_IMG_3582.GIF People can tune those (increase frequency) by removing something of the material. or add something to decrease frequency. Those are not very stable compared to a crystal controlled PLL.
>>No, there is no motion. Each tube is a shorted coaxial transmission >>line. The dielectric constant of the ceramic is so high that the line >>is short relative to the round-trip frequency. In the filter, the CCRs >>are coupled somehow, classic multiple-resonator math.
dielectric resonators! Anyways, now we know what we talk about.
On Sep 13, 2018, John Larkin wrote
(in article<ratkpdd8tm9gdtnqvmup0ip6rrjlmritjk@4ax.com>):

> On Thu, 13 Sep 2018 01:32:15 -0700 (PDT), whit3rd<whit3rd@gmail.com> > wrote: > > > On Wednesday, September 12, 2018 at 8:04:55 PM UTC-7, bill....@ieee.org > > wrote: > > > On Thursday, September 13, 2018 at 6:09:16 AM UTC+10, John Larkin wrote: > > > > > > Spark gaps can be impressive! > > > > > > But erosive. And the glow-to-arc transition takes closer a microsecond > > > than a picosecond. > > > > Erosion is real; there's a molybdenum electrode with a few grams missing > > in my junk box. The platinum button in a spark plug, though, lasts quite a > > while > > with modest currents. Probably the metal ions just aren't part of that kind > > of arc. > > Does anybody know what this is? > > <https://www.dropbox.com/s/np4s7ifgg5f4gbz/DSC01841.JPG?raw=1> > > <https://www.dropbox.com/s/6ckipx3z8v4nf72/DSC01844.JPG?raw=1> > > Spark gap? Waveguide T/R switch?
I&rsquo;d say HV spark gap. It does not look like it world work as a T/R switch - wrong shape, although I suppose it could be between two pillars transverse to a rectangular waveguide (shorting the long walls). Joe Gwinn