On Sun, 19 Dec 2021 16:52:25 GMT, Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> wrote:>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.I used to use selenium solar cells as photoreceivers. A flashlight bulb and a selenium-cell receiver made a surprisingly good audio link. I wonder what the selenium efficiency was. 1% ? I also used a Ge transistor in a flashlight reflector as a thermal IR detector. It could detect my hand from a foot or two away. -- I yam what I yam - Popeye
$161 oscilloscope
Started by ●December 17, 2021
Reply by ●December 19, 20212021-12-19
Reply by ●December 19, 20212021-12-19
On a sunny day (Sun, 19 Dec 2021 09:40:29 -0800) it happened jlarkin@highlandsniptechnology.com wrote in <9crurg9b3tl4sq9pns0tlu1dv6k0fi02qm@4ax.com>:>On Sun, 19 Dec 2021 16:52:25 GMT, Jan Panteltje ><pNaOnStPeAlMtje@yahoo.com> wrote: > >>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. > >I used to use selenium solar cells as photoreceivers. A flashlight >bulb and a selenium-cell receiver made a surprisingly good audio link. > >I wonder what the selenium efficiency was. 1% ?Googing (it that knows [almost] everything) for 'selenium solar cell efficiency' gives scholar articles, 5.7%.>I also used a Ge transistor in a flashlight reflector as a thermal IR >detector. It could detect my hand from a foot or two away.Nice, did you just measure output of the transistor or use it in some powered circuit with gain? I still have some OC71 (I think it is) here that I took from old army equipment.
Reply by ●December 19, 20212021-12-19
On Sun, 19 Dec 2021 20:02:42 GMT, Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> wrote:>On a sunny day (Sun, 19 Dec 2021 09:40:29 -0800) it happened >jlarkin@highlandsniptechnology.com wrote in ><9crurg9b3tl4sq9pns0tlu1dv6k0fi02qm@4ax.com>: > >>On Sun, 19 Dec 2021 16:52:25 GMT, Jan Panteltje >><pNaOnStPeAlMtje@yahoo.com> wrote: >> >>>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. >> >>I used to use selenium solar cells as photoreceivers. A flashlight >>bulb and a selenium-cell receiver made a surprisingly good audio link. >> >>I wonder what the selenium efficiency was. 1% ? > >Googing (it that knows [almost] everything) for 'selenium solar cell efficiency' gives scholar articles, 5.7%. > > >>I also used a Ge transistor in a flashlight reflector as a thermal IR >>detector. It could detect my hand from a foot or two away. > >Nice, did you just measure output of the transistor or use it in some powered circuit with gain? >I still have some OC71 (I think it is) here that I took from old army equipment.It has been a while. I think I put it in series with a battery and a pot and a mA meter and ran it partly into thermal runaway, which greatly increased the sensitivity. I did a lot of crazy stuff as a kid. Flashtube/PMT lidar. Poisonous HV Kerr cells. Thyratrons dumping caps into auto ignition coils. Filament-controlled HV rectifiers on neon sign transformers charging big oil caps. Giant electrolytic cap bank magnetizers. Radioactive stuff. All kinds of fun dangerous things. -- I yam what I yam - Popeye
Reply by ●December 19, 20212021-12-19
Jan Panteltje 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 >I think the first one I bought was a TR01-C, a TO3-packaged germanium made by IR. (I think it was germanium, anyway, but I was 11 years old, so I don't suppose I had any idea of the distinction.) I haven't been able to pull up a datasheet on it. Cheers 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 20, 20212021-12-20
On Sun, 19 Dec 2021 16:18:54 -0500, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>Jan Panteltje 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 >> > >I think the first one I bought was a TR01-C, a TO3-packaged germanium >made by IR. (I think it was germanium, anyway, but I was 11 years old, >so I don't suppose I had any idea of the distinction.) I haven't been >able to pull up a datasheet on it. > >Cheers > >Phil HobbsNTE calls this an equivalent - probably close enough: https://weisd.com/uploads/product/sheet_pdf/3758/NTE121.pdf ft of 300kHz .. it's hard to be worse than a 2N3055 but that does it. -- Best regards, Spehro Pefhany
Reply by ●December 20, 20212021-12-20
On a sunny day (Sun, 19 Dec 2021 12:50:37 -0800) it happened jlarkin@highlandsniptechnology.com wrote in <t46vrghsjiqpgakhn3c322vgirf37d1sc3@4ax.com>:>On Sun, 19 Dec 2021 20:02:42 GMT, Jan Panteltje ><pNaOnStPeAlMtje@yahoo.com> wrote: > >>On a sunny day (Sun, 19 Dec 2021 09:40:29 -0800) it happened >>jlarkin@highlandsniptechnology.com wrote in >><9crurg9b3tl4sq9pns0tlu1dv6k0fi02qm@4ax.com>: >> >>>On Sun, 19 Dec 2021 16:52:25 GMT, Jan Panteltje >>><pNaOnStPeAlMtje@yahoo.com> wrote: >>> >>>>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. >>> >>>I used to use selenium solar cells as photoreceivers. A flashlight >>>bulb and a selenium-cell receiver made a surprisingly good audio link. >>> >>>I wonder what the selenium efficiency was. 1% ? >> >>Googing (it that knows [almost] everything) for 'selenium solar cell efficiency' gives scholar articles, 5.7%. >> >> >>>I also used a Ge transistor in a flashlight reflector as a thermal IR >>>detector. It could detect my hand from a foot or two away. >> >>Nice, did you just measure output of the transistor or use it in some powered circuit with gain? >>I still have some OC71 (I think it is) here that I took from old army equipment. > >It has been a while. I think I put it in series with a battery and a >pot and a mA meter and ran it partly into thermal runaway, which >greatly increased the sensitivity.I may scrape the paint of an OC71 and see if it sees me in IR..>I did a lot of crazy stuff as a kid. Flashtube/PMT lidar. Poisonous HV >Kerr cells. Thyratrons dumping caps into auto ignition coils. >Filament-controlled HV rectifiers on neon sign transformers charging >big oil caps. Giant electrolytic cap bank magnetizers. Radioactive >stuff. All kinds of fun dangerous things.Yea, I remeber having a big round TV CRT with HV generated by an audio amp feeding into a car ignition coil, on my bed. That was also the horizontal scan IIRC. And then an other audio amp on the vertical deflection coils. My oscilloscope! No sync... Dangerous, implosion danger. In my last year at highschool I tried donating it to our physics teacher, but he did not want it (should have made a nice display in the auditorium) maybe he was afraid of it?, so the tube went back to the local TV repair shop where I got it from. BIG scope! Before that all sort of RF transmitters, even one with transistors, had our own radio FM station in the basement. :-) Before that 1.5 V tubes. Before that crystal radios.. Now we are in the early fifties. Chemicals? I build some thing that increased pressure in some can, and put it under the teahers desk, the lid went boom after a while. The danger was not much in the boom but in me being kicked out of school... Not that I gave a dime in those years, parents then send me to a boarding school... You shall study. Rebellion? Sinatra 'I did it my way'
Reply by ●December 20, 20212021-12-20
On 19/12/21 21:18, Phil Hobbs wrote:> Jan Panteltje 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 >> > > I think the first one I bought was a TR01-C, a TO3-packaged germanium made by > IR.� (I think it was germanium, anyway, but I was 11 years old, so I don't > suppose I had any idea of the distinction.)� I haven't been able to pull up a > datasheet on it.Mine came in the Philips EE-20 kit produced "63-65?" which would make me around 9. I still have a few of the parts, sad to say. (Yes, the rest of my house is as that implies, compounded by being in the middle of clearing my parents' house) The manual was remarkably good: - top half explained circuit theory - bottom half explained construction techniques Hans Otten seems to have a pleasing fetish for the Philips EE kits :) http://www.hansotten.com/electronic-kits/ee-series/ee8-ee20-a20/
Reply by ●December 20, 20212021-12-20
On Mon, 20 Dec 2021 07:56:24 GMT, Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> wrote:>On a sunny day (Sun, 19 Dec 2021 12:50:37 -0800) it happened >jlarkin@highlandsniptechnology.com wrote in ><t46vrghsjiqpgakhn3c322vgirf37d1sc3@4ax.com>: > >>On Sun, 19 Dec 2021 20:02:42 GMT, Jan Panteltje >><pNaOnStPeAlMtje@yahoo.com> wrote: >> >>>On a sunny day (Sun, 19 Dec 2021 09:40:29 -0800) it happened >>>jlarkin@highlandsniptechnology.com wrote in >>><9crurg9b3tl4sq9pns0tlu1dv6k0fi02qm@4ax.com>: >>> >>>>On Sun, 19 Dec 2021 16:52:25 GMT, Jan Panteltje >>>><pNaOnStPeAlMtje@yahoo.com> wrote: >>>> >>>>>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. >>>> >>>>I used to use selenium solar cells as photoreceivers. A flashlight >>>>bulb and a selenium-cell receiver made a surprisingly good audio link. >>>> >>>>I wonder what the selenium efficiency was. 1% ? >>> >>>Googing (it that knows [almost] everything) for 'selenium solar cell efficiency' gives scholar articles, 5.7%. >>> >>> >>>>I also used a Ge transistor in a flashlight reflector as a thermal IR >>>>detector. It could detect my hand from a foot or two away. >>> >>>Nice, did you just measure output of the transistor or use it in some powered circuit with gain? >>>I still have some OC71 (I think it is) here that I took from old army equipment. >> >>It has been a while. I think I put it in series with a battery and a >>pot and a mA meter and ran it partly into thermal runaway, which >>greatly increased the sensitivity. > >I may scrape the paint of an OC71 and see if it sees me in IR.. > > >>I did a lot of crazy stuff as a kid. Flashtube/PMT lidar. Poisonous HV >>Kerr cells. Thyratrons dumping caps into auto ignition coils. >>Filament-controlled HV rectifiers on neon sign transformers charging >>big oil caps. Giant electrolytic cap bank magnetizers. Radioactive >>stuff. All kinds of fun dangerous things. > >Yea, I remeber having a big round TV CRT with HV generated by an audio amp feeding into a car ignition coil, on my bed. >That was also the horizontal scan IIRC. >And then an other audio amp on the vertical deflection coils. >My oscilloscope! No sync... >Dangerous, implosion danger. >In my last year at highschool I tried donating it to our physics teacher, but he did not want it (should have made a nice display in the auditorium) >maybe he was afraid of it?, so the tube went back to the local TV repair shop where I got it from. >BIG scope! >Before that all sort of RF transmitters, even one with transistors, had our own radio FM station in the basement. :-) >Before that 1.5 V tubes. >Before that crystal radios.. Now we are in the early fifties. >Chemicals? I build some thing that increased pressure in some can, and put it under the teahers desk, the lid went boom after a while. >The danger was not much in the boom but in me being kicked out of school... >Not that I gave a dime in those years, parents then send me to a boarding school... >You shall study. >Rebellion? > >Sinatra 'I did it my way'Kids are so much more protected now, and so much more afraid. -- I yam what I yam - Popeye
Reply by ●December 20, 20212021-12-20
On Monday, December 20, 2021 at 11:28:36 AM UTC-4, jla...@highlandsniptechnology.com wrote:> On Mon, 20 Dec 2021 07:56:24 GMT, Jan Panteltje > >Chemicals? I build some thing that increased pressure in some can, and put it under the teahers desk, the lid went boom after a while. > >The danger was not much in the boom but in me being kicked out of school... > >Not that I gave a dime in those years, parents then send me to a boarding school... > >You shall study. > >Rebellion? > > > >Sinatra 'I did it my way' > Kids are so much more protected now, and so much more afraid.It shows that the average age in this group is over 60. The irony is that the old line is getting old enough that they are fading away and the average age is probably getting younger now. After all, none of us keep getting older indefinitely. -- Rick C. -- Get 1,000 miles of free Supercharging -- Tesla referral code - https://ts.la/richard11209
Reply by ●December 20, 20212021-12-20
Spehro Pefhany wrote:> On Sun, 19 Dec 2021 16:18:54 -0500, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> Jan Panteltje 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 >>> >> >> I think the first one I bought was a TR01-C, a TO3-packaged germanium >> made by IR. (I think it was germanium, anyway, but I was 11 years old, >> so I don't suppose I had any idea of the distinction.) I haven't been >> able to pull up a datasheet on it. >> >> Cheers >> >> Phil Hobbs > > NTE calls this an equivalent - probably close enough: > https://weisd.com/uploads/product/sheet_pdf/3758/NTE121.pdf > > ft of 300kHz .. it's hard to be worse than a 2N3055 but that does it. > >Looks about right, thanks. It was a megaphone project from a book--used a carbon mic button, a speaker, and +-3V from four AA cells. Worked fine but really chewed batteries. Cheers 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