In article <4b13b185-9903-447c-8069-e8aaf65c4c3an@googlegroups.com>, richsulinengineer@gmail.com says...> > Thanks Jan. Fascinating, i looked over the website. > SDRs are a vast area to explore, > if not for testing application, just for fun. > Another thing to add to my "someday" list of projects. > (when all those time-demands cease.). > > >They are for fun. I have one I paid aobut $ 120 and it goes from about 10 kHz to 2 GHz. It will let you set up multi receivers in a 10 MHz spread. Interisting to try and listen to 4 or 5 ham repeaters at the same time. Even the $ 10 to $ 20 TV type SDR that some software lets you listen in on many other things works well for the price.
$161 oscilloscope
Started by ●December 17, 2021
Reply by ●December 18, 20212021-12-18
Reply by ●December 18, 20212021-12-18
On Saturday, December 18, 2021 at 8:44:33 AM UTC-8, Phil Hobbs wrote:> And with 1000x the close-in phase noise. :(They have gotten better lately. More like 10x: http://www.miles.io/LMX2820_8672A_8663A.png Of course, the plot that ultimately matters is this one: http://www.miles.io/capture.png -- john, KE5FX
Reply by ●December 18, 20212021-12-18
On Saturday, December 18, 2021 at 4:51:26 PM UTC, Phil Hobbs wrote: [snip]> > > I'd way rather have a stack of boat anchors for the same money. My lab > has nearly $2M worth of top-of-the-line test gear (at list prices) that > I've paid probably $50k for over the years. > > SDR-style spectrum analyzers are okay for spur chasing, but mostly > useless for the kind of RF stuff I do, which requires low phase noise. >[snip] Indeed, I agree, the boat-anchors deserve love too. I'm not kicking them out of the party. Although todays gear seems more boatier and less anchory than those of previous generations' The labs at work are full of such anchors. (We have a tradition of buying only new, not used, BTW.) I have a new test coming up that will need to be "mobile" (fixed location, but in the field). So I'll be investigating what kind of performance is possible from a small size form factor. And not requiring an AC mains power generator! cheers, RS
Reply by ●December 18, 20212021-12-18
On Saturday, December 18, 2021 at 10:35:44 PM UTC, Tom Gardner wrote: [snip]> That's why it was SOP to "repurpose" transistors scavenged from > redundant PCBs. My school even had some on the floor in the > "photographic darkroom", and my physics teacher was more than > happy for me to take a couple of boards.+1 this. My parts bins still have a some of those 2N404, 2SB74, & other Ge rescues. Scavenging was my SOP too. Tho' I long abandoned all the non-solid-state (tube) stuff.... even a nice Heathkit tube tester. If I only knew then..
Reply by ●December 19, 20212021-12-19
jlarkin@highlandsniptechnology.com wrote:> On Sat, 18 Dec 2021 16:28:08 -0500, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> jlarkin@highlandsniptechnology.com wrote: >>> On Sat, 18 Dec 2021 08:27:49 -0500, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> Rich S wrote: >>>>> On Friday, December 17, 2021 at 10:54:41 PM UTC, John Larkin wrote: >>>>>> On Fri, 17 Dec 2021 16:32:48 -0500, Phil Hobbs >>>>>> <pcdhSpamM...@electrooptical.net> wrote: >>>>>> >>>>>>> John Larkin wrote: >>>>>>>> I was looking for something else and this showed up: >>>>>>>> >>>>>>>> https://www.amazon.com/s?k=0751300436685&crid=21WX22FGW2XXG&sprefix=0751300436685%2Caps%2C262&ref=nb_sb_noss >>>>>>>> >>>>>>>> Amazing. Someone could set up a garage lab and do some serious stuff >>>>>>>> really cheap these days. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> Potentially pretty useful, especially in a tool bag. >>>>>>> >>>>>>> Cheers >>>>>>> >>>>>>> Phil Hobbs >>>>>> I could keep one at home. Or in my car. >>>>>> -- >>>>>> >>>>>> If a man will begin with certainties, he shall end with doubts, >>>>>> but if he will be content to begin with doubts he shall end in certainties. >>>>>> Francis Bacon >>>>> >>>>> "Debugging Weapon" >>>>> finally, Amazon is selling weapons. >>>>> Kill those lousy oscillations. >>>>> >>>> >>>> Not with a 100 MHz scope! I did see one at 38 MHz a couple of months >>>> ago, but it's more usually 300 MHz or above. (My current record is 14 >>>> GHz iirc.) It's pretty cool to be able to get magic 60 GHz transistors >>>> for 20 cents. >>>> >>>> I remember designing 70-MHz crystal oscillators with 2N5179s back in the >>>> day, because 2N3904s were slightly too slow. (Yikes, that was 40 years >>>> ago!) >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>> In my mis-spent youth I designed an RC emitter follower + 7414 schmitt >>> gate as a system power-on reset. The 2N2219 oscillated so hard at 100 >>> MHz it never got the gate input high. >>> >>> Transistors are so much better now! >> >> Of course a CK722 would probably have worked too. ;) > > No, I needed an NPN.You didn't have a spare inverter section available?> > But CK722 was my first transistor. It cost $7, a couple of months' > allowance. > > https://www.dropbox.com/s/wuv7xjd5jg1i3lx/Ck722-0A.JPG?raw=1Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●December 19, 20212021-12-19
On a sunny day (Sat, 18 Dec 2021 18:00:32 -0500) it happened Ralph Mowery <rmowery42@charter.net> wrote in <MPG.3c28321d7ab2556b989ba9@news.eternal-september.org>:>In article <4b13b185-9903-447c-8069-e8aaf65c4c3an@googlegroups.com>, >richsulinengineer@gmail.com says... >> >> Thanks Jan. Fascinating, i looked over the website. >> SDRs are a vast area to explore, >> if not for testing application, just for fun. >> Another thing to add to my "someday" list of projects. >> (when all those time-demands cease.). >> >> >> > >Even the $ 10 to $ 20 TV type SDR that some software lets you listen in >on many other things works well for the price. >They are for fun. I have one I paid aobut $ 120 and it goes from about >10 kHz to 2 GHz. It will let you set up multi receivers in a 10 MHz >spread. Interisting to try and listen to 4 or 5 ham repeaters at the >same time.Yes, even did GPS reception with my 30$ stick. This guy showed how to do it: http://michelebavaro.blogspot.com/2012/04/spring-news-in-gnss-and-sdr-domain.html scroll down to 'panteltje' in replies my test: http://panteltje.com/pub/run_50_outside_2728000.gif
Reply by ●December 19, 20212021-12-19
On a sunny day (Sat, 18 Dec 2021 14:27:17 -0800) it happened jlarkin@highlandsniptechnology.com wrote in <srnsrglr1qa6arpsbg35bhqno86fu88fef@4ax.com>:>On Sat, 18 Dec 2021 16:28:08 -0500, Phil Hobbs ><pcdhSpamMeSenseless@electrooptical.net> wrote: > >>jlarkin@highlandsniptechnology.com wrote: >>> On Sat, 18 Dec 2021 08:27:49 -0500, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> Rich S wrote: >>>>> On Friday, December 17, 2021 at 10:54:41 PM UTC, John Larkin wrote: >>>>>> On Fri, 17 Dec 2021 16:32:48 -0500, Phil Hobbs >>>>>> <pcdhSpamM...@electrooptical.net> wrote: >>>>>> >>>>>>> John Larkin wrote: >>>>>>>> I was looking for something else and this showed up: >>>>>>>> >>>>>>>> https://www.amazon.com/s?k=0751300436685&crid=21WX22FGW2XXG&sprefix=0751300436685%2Caps%2C262&ref=nb_sb_noss >>>>>>>> >>>>>>>> Amazing. Someone could set up a garage lab and do some serious stuff >>>>>>>> really cheap these days. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> Potentially pretty useful, especially in a tool bag. >>>>>>> >>>>>>> Cheers >>>>>>> >>>>>>> Phil Hobbs >>>>>> I could keep one at home. Or in my car. >>>>>> -- >>>>>> >>>>>> If a man will begin with certainties, he shall end with doubts, >>>>>> but if he will be content to begin with doubts he shall end in certainties. >>>>>> Francis Bacon >>>>> >>>>> "Debugging Weapon" >>>>> finally, Amazon is selling weapons. >>>>> Kill those lousy oscillations. >>>>> >>>> >>>> Not with a 100 MHz scope! I did see one at 38 MHz a couple of months >>>> ago, but it's more usually 300 MHz or above. (My current record is 14 >>>> GHz iirc.) It's pretty cool to be able to get magic 60 GHz transistors >>>> for 20 cents. >>>> >>>> I remember designing 70-MHz crystal oscillators with 2N5179s back in the >>>> day, because 2N3904s were slightly too slow. (Yikes, that was 40 years >>>> ago!) >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>> In my mis-spent youth I designed an RC emitter follower + 7414 schmitt >>> gate as a system power-on reset. The 2N2219 oscillated so hard at 100 >>> MHz it never got the gate input high. >>> >>> Transistors are so much better now! >> >>Of course a CK722 would probably have worked too. ;) > >No, I needed an NPN. > >But CK722 was my first transistor. It cost $7, a couple of months' >allowance. > >https://www.dropbox.com/s/wuv7xjd5jg1i3lx/Ck722-0A.JPG?raw=1My first transistor was the OC13 (Philips) Ge PNP 10mA LF https://www.radiomuseum.org/tubes/tube_oc13.html
Reply by ●December 19, 20212021-12-19
On Sat, 18 Dec 2021 23:57:23 -0500, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>jlarkin@highlandsniptechnology.com wrote: >> On Sat, 18 Dec 2021 16:28:08 -0500, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> jlarkin@highlandsniptechnology.com wrote: >>>> On Sat, 18 Dec 2021 08:27:49 -0500, Phil Hobbs >>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>> >>>>> Rich S wrote: >>>>>> On Friday, December 17, 2021 at 10:54:41 PM UTC, John Larkin wrote: >>>>>>> On Fri, 17 Dec 2021 16:32:48 -0500, Phil Hobbs >>>>>>> <pcdhSpamM...@electrooptical.net> wrote: >>>>>>> >>>>>>>> John Larkin wrote: >>>>>>>>> I was looking for something else and this showed up: >>>>>>>>> >>>>>>>>> https://www.amazon.com/s?k=0751300436685&crid=21WX22FGW2XXG&sprefix=0751300436685%2Caps%2C262&ref=nb_sb_noss >>>>>>>>> >>>>>>>>> Amazing. Someone could set up a garage lab and do some serious stuff >>>>>>>>> really cheap these days. >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> Potentially pretty useful, especially in a tool bag. >>>>>>>> >>>>>>>> Cheers >>>>>>>> >>>>>>>> Phil Hobbs >>>>>>> I could keep one at home. Or in my car. >>>>>>> -- >>>>>>> >>>>>>> If a man will begin with certainties, he shall end with doubts, >>>>>>> but if he will be content to begin with doubts he shall end in certainties. >>>>>>> Francis Bacon >>>>>> >>>>>> "Debugging Weapon" >>>>>> finally, Amazon is selling weapons. >>>>>> Kill those lousy oscillations. >>>>>> >>>>> >>>>> Not with a 100 MHz scope! I did see one at 38 MHz a couple of months >>>>> ago, but it's more usually 300 MHz or above. (My current record is 14 >>>>> GHz iirc.) It's pretty cool to be able to get magic 60 GHz transistors >>>>> for 20 cents. >>>>> >>>>> I remember designing 70-MHz crystal oscillators with 2N5179s back in the >>>>> day, because 2N3904s were slightly too slow. (Yikes, that was 40 years >>>>> ago!) >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>> >>>> In my mis-spent youth I designed an RC emitter follower + 7414 schmitt >>>> gate as a system power-on reset. The 2N2219 oscillated so hard at 100 >>>> MHz it never got the gate input high. >>>> >>>> Transistors are so much better now! >>> >>> Of course a CK722 would probably have worked too. ;) >> >> No, I needed an NPN. > >You didn't have a spare inverter section available?It was a military job and we were supposed to use JAN-TX silicon transistors. I wrote an elaborate bit of nonsense why we had to use a commercial part (raving about capacitances and stuff) and we got away with it, out of frankly stated admiration for my BS skills. -- I yam what I yam - Popeye
Reply by ●December 19, 20212021-12-19
On Sun, 19 Dec 2021 06:27:13 GMT, Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> wrote:>On a sunny day (Sat, 18 Dec 2021 14:27:17 -0800) it happened >jlarkin@highlandsniptechnology.com wrote in ><srnsrglr1qa6arpsbg35bhqno86fu88fef@4ax.com>: > >>On Sat, 18 Dec 2021 16:28:08 -0500, Phil Hobbs >><pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>>jlarkin@highlandsniptechnology.com wrote: >>>> On Sat, 18 Dec 2021 08:27:49 -0500, Phil Hobbs >>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>> >>>>> Rich S wrote: >>>>>> On Friday, December 17, 2021 at 10:54:41 PM UTC, John Larkin wrote: >>>>>>> On Fri, 17 Dec 2021 16:32:48 -0500, Phil Hobbs >>>>>>> <pcdhSpamM...@electrooptical.net> wrote: >>>>>>> >>>>>>>> John Larkin wrote: >>>>>>>>> I was looking for something else and this showed up: >>>>>>>>> >>>>>>>>> https://www.amazon.com/s?k=0751300436685&crid=21WX22FGW2XXG&sprefix=0751300436685%2Caps%2C262&ref=nb_sb_noss >>>>>>>>> >>>>>>>>> Amazing. Someone could set up a garage lab and do some serious stuff >>>>>>>>> really cheap these days. >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> Potentially pretty useful, especially in a tool bag. >>>>>>>> >>>>>>>> Cheers >>>>>>>> >>>>>>>> Phil Hobbs >>>>>>> I could keep one at home. Or in my car. >>>>>>> -- >>>>>>> >>>>>>> If a man will begin with certainties, he shall end with doubts, >>>>>>> but if he will be content to begin with doubts he shall end in certainties. >>>>>>> Francis Bacon >>>>>> >>>>>> "Debugging Weapon" >>>>>> finally, Amazon is selling weapons. >>>>>> Kill those lousy oscillations. >>>>>> >>>>> >>>>> Not with a 100 MHz scope! I did see one at 38 MHz a couple of months >>>>> ago, but it's more usually 300 MHz or above. (My current record is 14 >>>>> GHz iirc.) It's pretty cool to be able to get magic 60 GHz transistors >>>>> for 20 cents. >>>>> >>>>> I remember designing 70-MHz crystal oscillators with 2N5179s back in the >>>>> day, because 2N3904s were slightly too slow. (Yikes, that was 40 years >>>>> ago!) >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>> >>>> In my mis-spent youth I designed an RC emitter follower + 7414 schmitt >>>> gate as a system power-on reset. The 2N2219 oscillated so hard at 100 >>>> MHz it never got the gate input high. >>>> >>>> Transistors are so much better now! >>> >>>Of course a CK722 would probably have worked too. ;) >> >>No, I needed an NPN. >> >>But CK722 was my first transistor. It cost $7, a couple of months' >>allowance. >> >>https://www.dropbox.com/s/wuv7xjd5jg1i3lx/Ck722-0A.JPG?raw=1 > >My first transistor was the OC13 (Philips) Ge PNP 10mA LF > https://www.radiomuseum.org/tubes/tube_oc13.htmlMine was prettier, a really nice translucent purple-blue paint on an aluminum can. Inside was a smaller hearing-aid transistor in a can, a reject from the main batches. -- I yam what I yam - Popeye
Reply by ●December 19, 20212021-12-19
On a sunny day (Sun, 19 Dec 2021 08:24:57 -0800) it happened jlarkin@highlandsniptechnology.com wrote in <u2nurg57orl5mk9ok6d7g6c4g2v7p0c0rn@4ax.com>:>On Sun, 19 Dec 2021 06:27:13 GMT, Jan Panteltje ><pNaOnStPeAlMtje@yahoo.com> wrote: > >>On a sunny day (Sat, 18 Dec 2021 14:27:17 -0800) it happened >>jlarkin@highlandsniptechnology.com wrote in >><srnsrglr1qa6arpsbg35bhqno86fu88fef@4ax.com>: >> >>>On Sat, 18 Dec 2021 16:28:08 -0500, Phil Hobbs >>><pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>>jlarkin@highlandsniptechnology.com wrote: >>>>> On Sat, 18 Dec 2021 08:27:49 -0500, Phil Hobbs >>>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>>> >>>>>> Rich S wrote: >>>>>>> On Friday, December 17, 2021 at 10:54:41 PM UTC, John Larkin wrote: >>>>>>>> On Fri, 17 Dec 2021 16:32:48 -0500, Phil Hobbs >>>>>>>> <pcdhSpamM...@electrooptical.net> wrote: >>>>>>>> >>>>>>>>> John Larkin wrote: >>>>>>>>>> I was looking for something else and this showed up: >>>>>>>>>> >>>>>>>>>> https://www.amazon.com/s?k=0751300436685&crid=21WX22FGW2XXG&sprefix=0751300436685%2Caps%2C262&ref=nb_sb_noss >>>>>>>>>> >>>>>>>>>> Amazing. Someone could set up a garage lab and do some serious stuff >>>>>>>>>> really cheap these days. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> Potentially pretty useful, especially in a tool bag. >>>>>>>>> >>>>>>>>> Cheers >>>>>>>>> >>>>>>>>> Phil Hobbs >>>>>>>> I could keep one at home. Or in my car. >>>>>>>> -- >>>>>>>> >>>>>>>> If a man will begin with certainties, he shall end with doubts, >>>>>>>> but if he will be content to begin with doubts he shall end in certainties. >>>>>>>> Francis Bacon >>>>>>> >>>>>>> "Debugging Weapon" >>>>>>> finally, Amazon is selling weapons. >>>>>>> Kill those lousy oscillations. >>>>>>> >>>>>> >>>>>> Not with a 100 MHz scope! I did see one at 38 MHz a couple of months >>>>>> ago, but it's more usually 300 MHz or above. (My current record is 14 >>>>>> GHz iirc.) It's pretty cool to be able to get magic 60 GHz transistors >>>>>> for 20 cents. >>>>>> >>>>>> I remember designing 70-MHz crystal oscillators with 2N5179s back in the >>>>>> day, because 2N3904s were slightly too slow. (Yikes, that was 40 years >>>>>> ago!) >>>>>> >>>>>> Cheers >>>>>> >>>>>> Phil Hobbs >>>>> >>>>> In my mis-spent youth I designed an RC emitter follower + 7414 schmitt >>>>> gate as a system power-on reset. The 2N2219 oscillated so hard at 100 >>>>> MHz it never got the gate input high. >>>>> >>>>> Transistors are so much better now! >>>> >>>>Of course a CK722 would probably have worked too. ;) >>> >>>No, I needed an NPN. >>> >>>But CK722 was my first transistor. It cost $7, a couple of months' >>>allowance. >>> >>>https://www.dropbox.com/s/wuv7xjd5jg1i3lx/Ck722-0A.JPG?raw=1 >> >>My first transistor was the OC13 (Philips) Ge PNP 10mA LF >> https://www.radiomuseum.org/tubes/tube_oc13.html > >Mine was prettier, a really nice translucent purple-blue paint on an >aluminum can. Inside was a smaller hearing-aid transistor in a can, a >reject from the main batches.Yes, but if you removed the paint from mine, then you could use it as photo transistor. It actually gave of some voltage when in the sun.
