On Friday, February 7, 2014 9:48:21 PM UTC-5, John Larkin wrote:> > 2001. UWB was very hot back then, but seems to have faded.Depends on the application but increased signal processing power ( and other advances) has enabled real time synthetic wideband.> > > > > > -- > > > > John Larkin Highland Technology Inc > > www.highlandtechnology.com jlarkin at highlandtechnology dot com > > > > Precision electronic instrumentation
Radar generating transistor circuit?
Started by ●February 7, 2014
Reply by ●February 8, 20142014-02-08
Reply by ●February 8, 20142014-02-08
On Friday, February 7, 2014 10:28:54 AM UTC-5, John Larkin wrote:> On Fri, 7 Feb 2014 05:09:02 -0800 (PST), haiticare2011@gmail.com wrote: >=20 >=20 >=20 > >I remember reading some while ago that LLL was working with fast switchi=ng transistors which generated "radar wavelength" signals. Then, as events = go, a Georgia Tech Prof. raised a stink since he had previously developed t= hose applications. Again, a vague memory. Does anyone recall this?>=20 > >TIA >=20 > >JB >=20 >=20 >=20 > The idea was broadband impulse radar, using step-recovery diode pulsers a=nd some>=20 > sort of audio-IF-range receive mixer. The guy was McKeon or something lik=e that.>=20 > He has a bunch of patents, and started his own company, but it didn't see=m to>=20 > go. >=20 >=20 >=20 >=20 >=20 > --=20 >=20 >=20 >=20 > John Larkin Highland Technology Inc >=20 > www.highlandtechnology.com jlarkin at highlandtechnology dot com =20 >=20 >=20 >=20 > Precision electronic instrumentationI am curious, what do the police traffic radars use ? They cannot=20 be very heavy or require very=20 heavy-duty power supplies.
Reply by ●February 8, 20142014-02-08
On Friday, February 7, 2014 11:05:00 AM UTC-5, bloggs.fred...@gmail.com wro= te:> On Friday, February 7, 2014 8:09:02 AM UTC-5, haitic...@gmail.com wrote: >=20 > > I remember reading some while ago that LLL was working with fast switch=ing transistors which generated "radar wavelength" signals. Then, as events= go, a Georgia Tech Prof. raised a stink since he had previously developed = those applications. Again, a vague memory. Does anyone recall this?>=20 > >=20 >=20 > > TIA >=20 > >=20 >=20 > > JB >=20 >=20 >=20 > Do you want to know about the radar circuits or the tiff between a bunch =of nobodies at overfunded cesspool bureaucracies??? This is a classic description of a lot of the academic old geezer profs, and their isolated, cut-off-from- reality work environment.
Reply by ●February 8, 20142014-02-08
John Larkin wrote:> On Fri, 07 Feb 2014 16:44:20 +0100, Jeroen Belleman<jeroen@nospam.please> > wrote: > >> On 2014-02-07 16:28, John Larkin wrote: >>> On Fri, 7 Feb 2014 05:09:02 -0800 (PST), haiticare2011@gmail.com >>> wrote: >>> >>>> I remember reading some while ago that LLL was working with fast >>>> switching transistors which generated "radar wavelength" signals. >>>> Then, as events go, a Georgia Tech Prof. raised a stink since he >>>> had previously developed those applications. Again, a vague memory. >>>> Does anyone recall this? TIA JB >>> >>> The idea was broadband impulse radar, using step-recovery diode >>> pulsers and some sort of audio-IF-range receive mixer. The guy was >>> McKeon or something like that. He has a bunch of patents, and started >>> his own company, but it didn't seem to go. >>> >>> >> >> McEwan? >> >> Jeroen Belleman > > Yes. Tom McEwan > > http://www.osti.gov/includes/doepatents/includes/MicroPower.pdf > > >Address Not Found www.osti.gov could not be found. Please check the name and try again.
Reply by ●February 8, 20142014-02-08
On Fri, 07 Feb 2014 21:59:55 -0800, Robert Baer <robertbaer@localnet.com> wrote:>John Larkin wrote: >> On Fri, 07 Feb 2014 16:44:20 +0100, Jeroen Belleman<jeroen@nospam.please> >> wrote: >> >>> On 2014-02-07 16:28, John Larkin wrote: >>>> On Fri, 7 Feb 2014 05:09:02 -0800 (PST), haiticare2011@gmail.com >>>> wrote: >>>> >>>>> I remember reading some while ago that LLL was working with fast >>>>> switching transistors which generated "radar wavelength" signals. >>>>> Then, as events go, a Georgia Tech Prof. raised a stink since he >>>>> had previously developed those applications. Again, a vague memory. >>>>> Does anyone recall this? TIA JB >>>> >>>> The idea was broadband impulse radar, using step-recovery diode >>>> pulsers and some sort of audio-IF-range receive mixer. The guy was >>>> McKeon or something like that. He has a bunch of patents, and started >>>> his own company, but it didn't seem to go. >>>> >>>> >>> >>> McEwan? >>> >>> Jeroen Belleman >> >> Yes. Tom McEwan >> >> http://www.osti.gov/includes/doepatents/includes/MicroPower.pdf >> >> >> >Address Not Found > >www.osti.gov could not be found. Please check the name and try again.Works for me. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation
Reply by ●February 8, 20142014-02-08
On Fri, 7 Feb 2014 20:39:19 -0800 (PST), dakupoto@gmail.com wrote:>On Friday, February 7, 2014 10:28:54 AM UTC-5, John Larkin wrote: >> On Fri, 7 Feb 2014 05:09:02 -0800 (PST), haiticare2011@gmail.com wrote: >> >> >> >> >I remember reading some while ago that LLL was working with fast switching transistors which generated "radar wavelength" signals. Then, as events go, a Georgia Tech Prof. raised a stink since he had previously developed those applications. Again, a vague memory. Does anyone recall this? >> >> >TIA >> >> >JB >> >> >> >> The idea was broadband impulse radar, using step-recovery diode pulsers and some >> >> sort of audio-IF-range receive mixer. The guy was McKeon or something like that. >> >> He has a bunch of patents, and started his own company, but it didn't seem to >> >> go. >> >> >> >> >> >> -- >> >> >> >> John Larkin Highland Technology Inc >> >> www.highlandtechnology.com jlarkin at highlandtechnology dot com >> >> >> >> Precision electronic instrumentation > >I am curious, what do the police >traffic radars use ? They cannot >be very heavy or require very >heavy-duty power supplies.Gunn-diode CW doppler, or lately rangefinder lasers. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation
Reply by ●February 8, 20142014-02-08
On Friday, February 7, 2014 11:05:00 AM UTC-5, bloggs.fred...@gmail.com wro= te:> On Friday, February 7, 2014 8:09:02 AM UTC-5, haitic...@gmail.com wrote: >=20 > > I remember reading some while ago that LLL was working with fast switch=ing transistors which generated "radar wavelength" signals. Then, as events= go, a Georgia Tech Prof. raised a stink since he had previously developed = those applications. Again, a vague memory. Does anyone recall this?>=20 > >=20 >=20 > > TIA >=20 > >=20 >=20 > > JB >=20 >=20 >=20 > Do you want to know about the radar circuits or the tiff between a bunch =of nobodies at overfunded cesspool bureaucracies??? the former, I think. :) jb
Reply by ●February 8, 20142014-02-08
<dakupoto@gmail.com> wrote in message news:d69405c1-8dfb-4a87-983c-33638ac1950a@googlegroups.com...> On Friday, February 7, 2014 10:28:54 AM UTC-5, John Larkin wrote: >> On Fri, 7 Feb 2014 05:09:02 -0800 (PST), haiticare2011@gmail.com wrote: >> >> >> >> >I remember reading some while ago that LLL was working with fast >> >switching transistors which generated "radar wavelength" signals. Then, >> >as events go, a Georgia Tech Prof. raised a stink since he had >> >previously developed those applications. Again, a vague memory. Does >> >anyone recall this? >> >> >TIA >> >> >JB >> >> >> >> The idea was broadband impulse radar, using step-recovery diode pulsers >> and some >> >> sort of audio-IF-range receive mixer. The guy was McKeon or something >> like that. >> >> He has a bunch of patents, and started his own company, but it didn't >> seem to >> >> go. >> >> >> >> >> >> -- >> >> >> >> John Larkin Highland Technology Inc >> >> www.highlandtechnology.com jlarkin at highlandtechnology dot com >> >> >> >> Precision electronic instrumentation > > I am curious, what do the police > traffic radars use ? They cannot > be very heavy or require very > heavy-duty power supplies.Didn't used to be so portable - years ago I zinged past a collection of coppers assembling various cables into a floor standing box about 1 1/2' cube. It was the first morning at the end of daylight saving, there was freezing rain and I was doing about 70. Further up the road I found myself gaining on a sports car that seemed to be in difficulty, from a good distance back I eased off the throttle but didn't touch the brakes. Suddenly the car just spun - a cyclist coming the other way ended up in someone's front garden.
Reply by ●February 8, 20142014-02-08
"miso" <miso@sushi.com> wrote in message news:ld3msp$d62$1@speranza.aioe.org...> Ian Field wrote: > >> >> >> <haiticare2011@gmail.com> wrote in message >> news:6473bf77-f37e-4207-81a1-7bba9945a7ba@googlegroups.com... >>> I remember reading some while ago that LLL was working with fast >>> switching transistors which generated "radar wavelength" signals. Then, >>> as events go, a Georgia Tech Prof. raised a stink since he had >>> previously >>> developed those applications. Again, a vague memory. Does anyone recall >>> this? >> >> On one of my downloading sprees, I got various radar circuit schematics >> with a smattering of transistor types and vintage stuff dating back to >> WW2. >> >> A prominent book on the site I think they might have come from is: >> gunplexer cookbook, if you search that you might find a site with all >> kinds of UHF/EHF military stuff. >> >> If you're doing really low power stuff, the ZTX415 avalanche transistor >> might do for producing narrow pulses - you go for a Vcc of 60V or more, >> your energy storage device is a tuned length of co-ax cable, you set the >> transistor up just short of breakdown and trigger it with a pulse to the >> base. Pulsewidths of a few nS are a typical application. > > How do you focus the energy? A dish is broadband, but the feed horn > generally is a band limited device.No idea - I only read little bits I can find about radar out of idle curiosity. Its my understanding so far, that waveguides can be tuned pretty sharp.
Reply by ●February 8, 20142014-02-08
On 8.2.14 19:01, Ian Field wrote:> > > "miso" <miso@sushi.com> wrote in message > news:ld3msp$d62$1@speranza.aioe.org... >> Ian Field wrote: >> >>> >>> >>> <haiticare2011@gmail.com> wrote in message >>> news:6473bf77-f37e-4207-81a1-7bba9945a7ba@googlegroups.com... >>>> I remember reading some while ago that LLL was working with fast >>>> switching transistors which generated "radar wavelength" signals. Then, >>>> as events go, a Georgia Tech Prof. raised a stink since he had >>>> previously >>>> developed those applications. Again, a vague memory. Does anyone recall >>>> this? >>> >>> On one of my downloading sprees, I got various radar circuit schematics >>> with a smattering of transistor types and vintage stuff dating back to >>> WW2. >>> >>> A prominent book on the site I think they might have come from is: >>> gunplexer cookbook, if you search that you might find a site with all >>> kinds of UHF/EHF military stuff. >>> >>> If you're doing really low power stuff, the ZTX415 avalanche transistor >>> might do for producing narrow pulses - you go for a Vcc of 60V or more, >>> your energy storage device is a tuned length of co-ax cable, you set the >>> transistor up just short of breakdown and trigger it with a pulse to the >>> base. Pulsewidths of a few nS are a typical application. >> >> How do you focus the energy? A dish is broadband, but the feed horn >> generally is a band limited device. > > No idea - I only read little bits I can find about radar out of idle > curiosity. > > Its my understanding so far, that waveguides can be tuned pretty sharp.You're probably thinking about cavity resonators. Waveguides are transmission lines, and they are not supposed to resonate. -- -TV
