Reply by Lasse Langwadt Christensen●May 27, 20162016-05-27
Den fredag den 27. maj 2016 kl. 18.10.40 UTC+2 skrev mrda...@gmail.com:
> On Wednesday, May 25, 2016 at 6:47:28 AM UTC-7, Phil Hobbs wrote:
> > On 05/24/2016 07:41 PM, klaus.kragelund@gmail.com wrote:
> > > Hey
> > >
> > > Been trying to find the post with the lossless snubber, with AFAIR a
> > > capacitor from the drain node to a regenerative point.
> > >
> > > I am working on a 2 switch flyback and some other schemes, but would
> > > like to try that novel idea out....
> > >
> > > Anyone knows a pointer to the thread?
> > >
> > > Regards
> > >
> > > Klaus
> > >
> > Well, there's The Vlad Memorial Antiseptic Converter, e.g.
> >
> > <http://electrooptical.net/www/sed/antiseptic_converter.asc>
> >
> > Cheers
> >
> > Phil Hobbs
> >
> > --
> > Dr Philip C D Hobbs
> > Principal Consultant
> > ElectroOptical Innovations LLC
> > Optics, Electro-optics, Photonics, Analog Electronics
> >
> > 160 North State Road #203
> > Briarcliff Manor NY 10510
> >
> > hobbs at electrooptical dot net
> > http://electrooptical.net
>
>
> Why did you name it the Vlad Memorial?
>
> :D
>
> Michael
On Wednesday, May 25, 2016 at 6:47:28 AM UTC-7, Phil Hobbs wrote:
> On 05/24/2016 07:41 PM, klaus.kragelund@gmail.com wrote:
> > Hey
> >
> > Been trying to find the post with the lossless snubber, with AFAIR a
> > capacitor from the drain node to a regenerative point.
> >
> > I am working on a 2 switch flyback and some other schemes, but would
> > like to try that novel idea out....
> >
> > Anyone knows a pointer to the thread?
> >
> > Regards
> >
> > Klaus
> >
> Well, there's The Vlad Memorial Antiseptic Converter, e.g.
>
> <http://electrooptical.net/www/sed/antiseptic_converter.asc>
>
> Cheers
>
> Phil Hobbs
>
> --
> Dr Philip C D Hobbs
> Principal Consultant
> ElectroOptical Innovations LLC
> Optics, Electro-optics, Photonics, Analog Electronics
>
> 160 North State Road #203
> Briarcliff Manor NY 10510
>
> hobbs at electrooptical dot net
> http://electrooptical.net
Why did you name it the Vlad Memorial?
:D
Michael
Reply by Tim Wescott●May 26, 20162016-05-26
On Thu, 26 May 2016 09:23:02 -0700, Jim Thompson wrote:
> On Thu, 26 May 2016 11:10:27 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>>On 05/25/2016 03:26 PM, John S wrote:
>>> On 5/25/2016 11:35 AM, Jim Thompson wrote:
>>>> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott
>>>> <tim@seemywebsite.com>
>>>> wrote:
>>>>
>>>>> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>>>>>
>>>>>> Hey
>>>>>>
>>>>>> Been trying to find the post with the lossless snubber, with AFAIR
>>>>>> a capacitor from the drain node to a regenerative point.
>>>>>>
>>>>>> I am working on a 2 switch flyback and some other schemes, but
>>>>>> would like to try that novel idea out....
>>>>>>
>>>>>> Anyone knows a pointer to the thread?
>>>>>>
>>>>>> Regards
>>>>>>
>>>>>> Klaus
>>>>>
>>>>> I'll have to go look at whatever clever idea I had. The circuit
>>>>> ended up not working but not, I think, because of my inadequate
>>>>> snubbing.
>>>>>
>>>>> A circuit that I did not work on directly, but which I know worked
>>>>> well,
>>>>> was a fairly high-power flyback that just had a diode-capacitor
>>>>> snubber,
>>>>> but which then had a switcher from the snubber cap's voltage back to
>>>>> the primary DC rail. I can't remember whether it was called an
>>>>> active snubber or a regenerative snubber, but the circuit worked.
>>>>>
>>>>> (The company went down the tubes -- it was a startup trying to make
>>>>> a super-efficient solar panel inverter that did not use
>>>>> electrolytics anywhere, and would, thus, "last forever". It was run
>>>>> by someone with a PhD in engineering, and I'm pretty sure it died
>>>>> due to lack of a sales and marketing network.)
>>>>
>>>> "It was run by someone with a _PhD_ in engineering" _is_ probably why
>>>> it failed >:-}
>>>>
>>>> ...Jim Thompson
>>>
>>> Why do you have to be so hateful? You're no jewel, yourself.
>>
>>Jim's just being Jim. Button pushing is what he does when he's bored,
>>like so many other denizens of SED. If he had a Ph.D., he'd be saying
>>the same about "undereducated engineers" or people who think that a MSEE
>>makes you a "master" like him. ;)
>>
>>He used to rag on me like that, until we collaborated on a project. ;)
>>
>>As far as competence goes, the worst engineer I've ever encountered had
>>a Ph.D. in "Industrial Engineering", a very nebulous field that (as I
>>belatedly discovered, to my cost) seems to be a dumping ground for
>>people who couldn't hack real engineering grad school.
>>
>>This guy was lead designer for a company that was hired to productize an
>>instrument proto of mine, one that worked very well but didn't look very
>>pretty. (*) Among other exploits, he coded up a digital lock-in--in
>>LabView--using *least squares curve fitting* to pull a sinusoid out of
>>noisy sampled data, instead of multiply-and-accumulate with N whole
>>cycles of the sine and cosine of the (known) frequency like a normal
>>person. (Turned out he knew zero signals-and-systems.) To make it
>>worse, he had a DC restore function that masked the problem to some
>>degree.
>>
>>Like most crappy detectors, it kinda sorta worked at high SNR, but fell
>>completely apart at noise levels that a real lock-in wouldn't even have
>>noticed. The client (an angel-funded start-up) called me back in at the
>>11th hour to iron it out, but there were so many onion layers of
>>crappiness in that project, and the crapmeisters had gone so far over
>>budget, that they ran out of money before I could find them all. A
>>pity--it's still a great gizmo.
>>
>>Cheers
>>
>>Phil Hobbs
>>
>>(*) It also used an RC airplane servo to rotate a diffraction grating,
>>which was fine as long as it had a preload spring. You do _not_ show
>>the FDA an instrument made with toy parts. ;)
>
> Let me amend (ever so slightly :-)... my contact with PhD's without
> significant "on-the-battle-field" experience has been pitiful...
> school-only-experience is a recipe for disaster.
I've worked with some PhD's _with_ experience, and they've been golden.
One of them is now a friend, who showed up doing contract software work
to get his on-the-ground software experience before he went off to be a
neural-network wonk.
He's the _only guy_ I've met who not only made money doing neural
networks (still does, AFAIK), but who worked for companies that made
money doing neural networks.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
I'm looking for work -- see my website!
Reply by John S●May 26, 20162016-05-26
On 5/26/2016 10:10 AM, Phil Hobbs wrote:
> On 05/25/2016 03:26 PM, John S wrote:
>> On 5/25/2016 11:35 AM, Jim Thompson wrote:
>>> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott <tim@seemywebsite.com>
>>> wrote:
>>>
>>>> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>>>>
>>>>> Hey
>>>>>
>>>>> Been trying to find the post with the lossless snubber, with AFAIR a
>>>>> capacitor from the drain node to a regenerative point.
>>>>>
>>>>> I am working on a 2 switch flyback and some other schemes, but would
>>>>> like to try that novel idea out....
>>>>>
>>>>> Anyone knows a pointer to the thread?
>>>>>
>>>>> Regards
>>>>>
>>>>> Klaus
>>>>
>>>> I'll have to go look at whatever clever idea I had. The circuit
>>>> ended up
>>>> not working but not, I think, because of my inadequate snubbing.
>>>>
>>>> A circuit that I did not work on directly, but which I know worked well,
>>>> was a fairly high-power flyback that just had a diode-capacitor snubber,
>>>> but which then had a switcher from the snubber cap's voltage back to the
>>>> primary DC rail. I can't remember whether it was called an active
>>>> snubber or a regenerative snubber, but the circuit worked.
>>>>
>>>> (The company went down the tubes -- it was a startup trying to make a
>>>> super-efficient solar panel inverter that did not use electrolytics
>>>> anywhere, and would, thus, "last forever". It was run by someone with a
>>>> PhD in engineering, and I'm pretty sure it died due to lack of a sales
>>>> and marketing network.)
>>>
>>> "It was run by someone with a _PhD_ in engineering" _is_ probably why
>>> it failed >:-}
>>>
>>> ...Jim Thompson
>>
>> Why do you have to be so hateful? You're no jewel, yourself.
>
> Jim's just being Jim. Button pushing is what he does when he's bored,
> like so many other denizens of SED. If he had a Ph.D., he'd be saying
> the same about "undereducated engineers" or people who think that a MSEE
> makes you a "master" like him. ;)
My business partner has a MSEE. It is my company but I made him "boss"
because he has sales, accounting, and more design experience than I. If
we butt heads, he wins because I felt that in a two-man company, one of
us needed the final say. He has never pulled the MSEE thing on me and,
in fact, he never brought it up until asked. He doesn't care about
credentials, just capabilities. And we agree on that.
> He used to rag on me like that, until we collaborated on a project. ;)
>
> As far as competence goes, the worst engineer I've ever encountered had
> a Ph.D. in "Industrial Engineering", a very nebulous field that (as I
> belatedly discovered, to my cost) seems to be a dumping ground for
> people who couldn't hack real engineering grad school.
>
> This guy was lead designer for a company that was hired to productize an
> instrument proto of mine, one that worked very well but didn't look very
> pretty. (*) Among other exploits, he coded up a digital lock-in--in
> LabView--using *least squares curve fitting* to pull a sinusoid out of
> noisy sampled data, instead of multiply-and-accumulate with N whole
> cycles of the sine and cosine of the (known) frequency like a normal
> person. (Turned out he knew zero signals-and-systems.) To make it
> worse, he had a DC restore function that masked the problem to some degree.
>
> Like most crappy detectors, it kinda sorta worked at high SNR, but fell
> completely apart at noise levels that a real lock-in wouldn't even have
> noticed. The client (an angel-funded start-up) called me back in at the
> 11th hour to iron it out, but there were so many onion layers of
> crappiness in that project, and the crapmeisters had gone so far over
> budget, that they ran out of money before I could find them all. A
> pity--it's still a great gizmo.
>
> Cheers
>
> Phil Hobbs
>
> (*) It also used an RC airplane servo to rotate a diffraction grating,
> which was fine as long as it had a preload spring. You do _not_ show
> the FDA an instrument made with toy parts. ;)
>
Reply by Phil Hobbs●May 26, 20162016-05-26
On 05/26/2016 12:23 PM, Jim Thompson wrote:
> On Thu, 26 May 2016 11:10:27 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>> On 05/25/2016 03:26 PM, John S wrote:
>>> On 5/25/2016 11:35 AM, Jim Thompson wrote:
>>>> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott <tim@seemywebsite.com>
>>>> wrote:
>>>>
>>>>> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>>>>>
>>>>>> Hey
>>>>>>
>>>>>> Been trying to find the post with the lossless snubber, with AFAIR a
>>>>>> capacitor from the drain node to a regenerative point.
>>>>>>
>>>>>> I am working on a 2 switch flyback and some other schemes, but would
>>>>>> like to try that novel idea out....
>>>>>>
>>>>>> Anyone knows a pointer to the thread?
>>>>>>
>>>>>> Regards
>>>>>>
>>>>>> Klaus
>>>>>
>>>>> I'll have to go look at whatever clever idea I had. The circuit
>>>>> ended up
>>>>> not working but not, I think, because of my inadequate snubbing.
>>>>>
>>>>> A circuit that I did not work on directly, but which I know worked well,
>>>>> was a fairly high-power flyback that just had a diode-capacitor snubber,
>>>>> but which then had a switcher from the snubber cap's voltage back to the
>>>>> primary DC rail. I can't remember whether it was called an active
>>>>> snubber or a regenerative snubber, but the circuit worked.
>>>>>
>>>>> (The company went down the tubes -- it was a startup trying to make a
>>>>> super-efficient solar panel inverter that did not use electrolytics
>>>>> anywhere, and would, thus, "last forever". It was run by someone with a
>>>>> PhD in engineering, and I'm pretty sure it died due to lack of a sales
>>>>> and marketing network.)
>>>>
>>>> "It was run by someone with a _PhD_ in engineering" _is_ probably why
>>>> it failed >:-}
>>>>
>>>> ...Jim Thompson
>>>
>>> Why do you have to be so hateful? You're no jewel, yourself.
>>
>> Jim's just being Jim. Button pushing is what he does when he's bored,
>> like so many other denizens of SED. If he had a Ph.D., he'd be saying
>> the same about "undereducated engineers" or people who think that a MSEE
>> makes you a "master" like him. ;)
>>
>> He used to rag on me like that, until we collaborated on a project. ;)
>>
>> As far as competence goes, the worst engineer I've ever encountered had
>> a Ph.D. in "Industrial Engineering", a very nebulous field that (as I
>> belatedly discovered, to my cost) seems to be a dumping ground for
>> people who couldn't hack real engineering grad school.
>>
>> This guy was lead designer for a company that was hired to productize an
>> instrument proto of mine, one that worked very well but didn't look very
>> pretty. (*) Among other exploits, he coded up a digital lock-in--in
>> LabView--using *least squares curve fitting* to pull a sinusoid out of
>> noisy sampled data, instead of multiply-and-accumulate with N whole
>> cycles of the sine and cosine of the (known) frequency like a normal
>> person. (Turned out he knew zero signals-and-systems.) To make it
>> worse, he had a DC restore function that masked the problem to some degree.
>>
>> Like most crappy detectors, it kinda sorta worked at high SNR, but fell
>> completely apart at noise levels that a real lock-in wouldn't even have
>> noticed. The client (an angel-funded start-up) called me back in at the
>> 11th hour to iron it out, but there were so many onion layers of
>> crappiness in that project, and the crapmeisters had gone so far over
>> budget, that they ran out of money before I could find them all. A
>> pity--it's still a great gizmo.
>>
>> Cheers
>>
>> Phil Hobbs
>>
>> (*) It also used an RC airplane servo to rotate a diffraction grating,
>> which was fine as long as it had a preload spring. You do _not_ show
>> the FDA an instrument made with toy parts. ;)
>
> Let me amend (ever so slightly :-)... my contact with PhD's without
> significant "on-the-battle-field" experience has been pitiful...
> school-only-experience is a recipe for disaster.
I wouldn't disagree. A 30-year-old Ph.D. has probably 2 years of work
experience. Of course it depends a lot on what his thesis project
was--somebody who just knows how to write signal processing code has a
lot to learn after graduating, whereas somebody who had to get real
hardware working is a much better bet.
And of course finding somebody who can do all of those things is always
a win, especially if he was a hobbyist as a kid.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
Reply by Jim Thompson●May 26, 20162016-05-26
On Thu, 26 May 2016 11:10:27 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
>On 05/25/2016 03:26 PM, John S wrote:
>> On 5/25/2016 11:35 AM, Jim Thompson wrote:
>>> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott <tim@seemywebsite.com>
>>> wrote:
>>>
>>>> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>>>>
>>>>> Hey
>>>>>
>>>>> Been trying to find the post with the lossless snubber, with AFAIR a
>>>>> capacitor from the drain node to a regenerative point.
>>>>>
>>>>> I am working on a 2 switch flyback and some other schemes, but would
>>>>> like to try that novel idea out....
>>>>>
>>>>> Anyone knows a pointer to the thread?
>>>>>
>>>>> Regards
>>>>>
>>>>> Klaus
>>>>
>>>> I'll have to go look at whatever clever idea I had. The circuit
>>>> ended up
>>>> not working but not, I think, because of my inadequate snubbing.
>>>>
>>>> A circuit that I did not work on directly, but which I know worked well,
>>>> was a fairly high-power flyback that just had a diode-capacitor snubber,
>>>> but which then had a switcher from the snubber cap's voltage back to the
>>>> primary DC rail. I can't remember whether it was called an active
>>>> snubber or a regenerative snubber, but the circuit worked.
>>>>
>>>> (The company went down the tubes -- it was a startup trying to make a
>>>> super-efficient solar panel inverter that did not use electrolytics
>>>> anywhere, and would, thus, "last forever". It was run by someone with a
>>>> PhD in engineering, and I'm pretty sure it died due to lack of a sales
>>>> and marketing network.)
>>>
>>> "It was run by someone with a _PhD_ in engineering" _is_ probably why
>>> it failed >:-}
>>>
>>> ...Jim Thompson
>>
>> Why do you have to be so hateful? You're no jewel, yourself.
>
>Jim's just being Jim. Button pushing is what he does when he's bored,
>like so many other denizens of SED. If he had a Ph.D., he'd be saying
>the same about "undereducated engineers" or people who think that a MSEE
>makes you a "master" like him. ;)
>
>He used to rag on me like that, until we collaborated on a project. ;)
>
>As far as competence goes, the worst engineer I've ever encountered had
>a Ph.D. in "Industrial Engineering", a very nebulous field that (as I
>belatedly discovered, to my cost) seems to be a dumping ground for
>people who couldn't hack real engineering grad school.
>
>This guy was lead designer for a company that was hired to productize an
>instrument proto of mine, one that worked very well but didn't look very
>pretty. (*) Among other exploits, he coded up a digital lock-in--in
>LabView--using *least squares curve fitting* to pull a sinusoid out of
>noisy sampled data, instead of multiply-and-accumulate with N whole
>cycles of the sine and cosine of the (known) frequency like a normal
>person. (Turned out he knew zero signals-and-systems.) To make it
>worse, he had a DC restore function that masked the problem to some degree.
>
>Like most crappy detectors, it kinda sorta worked at high SNR, but fell
>completely apart at noise levels that a real lock-in wouldn't even have
>noticed. The client (an angel-funded start-up) called me back in at the
>11th hour to iron it out, but there were so many onion layers of
>crappiness in that project, and the crapmeisters had gone so far over
>budget, that they ran out of money before I could find them all. A
>pity--it's still a great gizmo.
>
>Cheers
>
>Phil Hobbs
>
>(*) It also used an RC airplane servo to rotate a diffraction grating,
>which was fine as long as it had a preload spring. You do _not_ show
>the FDA an instrument made with toy parts. ;)
Let me amend (ever so slightly :-)... my contact with PhD's without
significant "on-the-battle-field" experience has been pitiful...
school-only-experience is a recipe for disaster.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I'm looking for work... see my website.
Reply by Phil Hobbs●May 26, 20162016-05-26
On 05/25/2016 03:26 PM, John S wrote:
> On 5/25/2016 11:35 AM, Jim Thompson wrote:
>> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott <tim@seemywebsite.com>
>> wrote:
>>
>>> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>>>
>>>> Hey
>>>>
>>>> Been trying to find the post with the lossless snubber, with AFAIR a
>>>> capacitor from the drain node to a regenerative point.
>>>>
>>>> I am working on a 2 switch flyback and some other schemes, but would
>>>> like to try that novel idea out....
>>>>
>>>> Anyone knows a pointer to the thread?
>>>>
>>>> Regards
>>>>
>>>> Klaus
>>>
>>> I'll have to go look at whatever clever idea I had. The circuit
>>> ended up
>>> not working but not, I think, because of my inadequate snubbing.
>>>
>>> A circuit that I did not work on directly, but which I know worked well,
>>> was a fairly high-power flyback that just had a diode-capacitor snubber,
>>> but which then had a switcher from the snubber cap's voltage back to the
>>> primary DC rail. I can't remember whether it was called an active
>>> snubber or a regenerative snubber, but the circuit worked.
>>>
>>> (The company went down the tubes -- it was a startup trying to make a
>>> super-efficient solar panel inverter that did not use electrolytics
>>> anywhere, and would, thus, "last forever". It was run by someone with a
>>> PhD in engineering, and I'm pretty sure it died due to lack of a sales
>>> and marketing network.)
>>
>> "It was run by someone with a _PhD_ in engineering" _is_ probably why
>> it failed >:-}
>>
>> ...Jim Thompson
>
> Why do you have to be so hateful? You're no jewel, yourself.
Jim's just being Jim. Button pushing is what he does when he's bored,
like so many other denizens of SED. If he had a Ph.D., he'd be saying
the same about "undereducated engineers" or people who think that a MSEE
makes you a "master" like him. ;)
He used to rag on me like that, until we collaborated on a project. ;)
As far as competence goes, the worst engineer I've ever encountered had
a Ph.D. in "Industrial Engineering", a very nebulous field that (as I
belatedly discovered, to my cost) seems to be a dumping ground for
people who couldn't hack real engineering grad school.
This guy was lead designer for a company that was hired to productize an
instrument proto of mine, one that worked very well but didn't look very
pretty. (*) Among other exploits, he coded up a digital lock-in--in
LabView--using *least squares curve fitting* to pull a sinusoid out of
noisy sampled data, instead of multiply-and-accumulate with N whole
cycles of the sine and cosine of the (known) frequency like a normal
person. (Turned out he knew zero signals-and-systems.) To make it
worse, he had a DC restore function that masked the problem to some degree.
Like most crappy detectors, it kinda sorta worked at high SNR, but fell
completely apart at noise levels that a real lock-in wouldn't even have
noticed. The client (an angel-funded start-up) called me back in at the
11th hour to iron it out, but there were so many onion layers of
crappiness in that project, and the crapmeisters had gone so far over
budget, that they ran out of money before I could find them all. A
pity--it's still a great gizmo.
Cheers
Phil Hobbs
(*) It also used an RC airplane servo to rotate a diffraction grating,
which was fine as long as it had a preload spring. You do _not_ show
the FDA an instrument made with toy parts. ;)
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
"master" like him.
hobbs at electrooptical dot net
http://electrooptical.net
Reply by Klaus Kragelund●May 26, 20162016-05-26
On Thursday, May 26, 2016 at 5:13:06 AM UTC+2, bill....@ieee.org wrote:
> On Thursday, May 26, 2016 at 9:05:03 AM UTC+10, Tim Wescott wrote:
> > On Wed, 25 May 2016 14:02:03 -0700, klaus.kragelund wrote:
> >
> > > On Wednesday, 25 May 2016 18:31:21 UTC+2, Tim Wescott wrote:
> > >> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
> > >>
> > >> > Hey
> > >> >
> > >> > Been trying to find the post with the lossless snubber, with AFAIR a
> > >> > capacitor from the drain node to a regenerative point.
> > >> >
> > >> > I am working on a 2 switch flyback and some other schemes, but would
> > >> > like to try that novel idea out....
> > >> >
> > >> > Anyone knows a pointer to the thread?
> > >> >
> > >> > Regards
> > >> >
> > >> > Klaus
> > >>
> > >> I'll have to go look at whatever clever idea I had. The circuit ended
> > >> up not working but not, I think, because of my inadequate snubbing.
> > >>
> > >> A circuit that I did not work on directly, but which I know worked
> > >> well, was a fairly high-power flyback that just had a diode-capacitor
> > >> snubber, but which then had a switcher from the snubber cap's voltage
> > >> back to the primary DC rail. I can't remember whether it was called an
> > >> active snubber or a regenerative snubber, but the circuit worked.
> > >>
> > > Yes, that's also a nice idea. Will have to try that sometime :-)
> > >
> > > Some patents are lurking on that implementation, so will have to be
> > > careful not to breach one of those
> >
> > I think that the other way I did it was to drive the coil primary with a
> > half-bridge. The top FET would get power from the leakage inductance and
> > give it back in the same cycle.
> >
> > I'm not sure if it's really a practical thing in practice, though -- it
> > never got beyond simulation.
>
> Sounds like the series version of the Baxandall Class-D oscillator, as opposed to the parallel version popularised by Jim Williams.
>
> http://sophia-elektronica.com/0344_001_Baxandal.pdf
>
> at figure 8. Baxandall didn't have MOSFETs to play with.
>
On Thursday, May 26, 2016 at 9:05:03 AM UTC+10, Tim Wescott wrote:
> On Wed, 25 May 2016 14:02:03 -0700, klaus.kragelund wrote:
>
> > On Wednesday, 25 May 2016 18:31:21 UTC+2, Tim Wescott wrote:
> >> On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
> >>
> >> > Hey
> >> >
> >> > Been trying to find the post with the lossless snubber, with AFAIR a
> >> > capacitor from the drain node to a regenerative point.
> >> >
> >> > I am working on a 2 switch flyback and some other schemes, but would
> >> > like to try that novel idea out....
> >> >
> >> > Anyone knows a pointer to the thread?
> >> >
> >> > Regards
> >> >
> >> > Klaus
> >>
> >> I'll have to go look at whatever clever idea I had. The circuit ended
> >> up not working but not, I think, because of my inadequate snubbing.
> >>
> >> A circuit that I did not work on directly, but which I know worked
> >> well, was a fairly high-power flyback that just had a diode-capacitor
> >> snubber, but which then had a switcher from the snubber cap's voltage
> >> back to the primary DC rail. I can't remember whether it was called an
> >> active snubber or a regenerative snubber, but the circuit worked.
> >>
> > Yes, that's also a nice idea. Will have to try that sometime :-)
> >
> > Some patents are lurking on that implementation, so will have to be
> > careful not to breach one of those
>
> I think that the other way I did it was to drive the coil primary with a
> half-bridge. The top FET would get power from the leakage inductance and
> give it back in the same cycle.
>
> I'm not sure if it's really a practical thing in practice, though -- it
> never got beyond simulation.
Sounds like the series version of the Baxandall Class-D oscillator, as opposed to the parallel version popularised by Jim Williams.
http://sophia-elektronica.com/0344_001_Baxandal.pdf
at figure 8. Baxandall didn't have MOSFETs to play with.
--
Bill Sloman, Sydney
Reply by ●May 26, 20162016-05-26
On Thursday, May 26, 2016 at 2:35:55 AM UTC+10, Jim Thompson wrote:
> On Wed, 25 May 2016 11:31:17 -0500, Tim Wescott <tim@seemywebsite.com>
> wrote:
>
> >On Tue, 24 May 2016 16:41:44 -0700, klaus.kragelund wrote:
>
> >> Been trying to find the post with the lossless snubber, with AFAIR a
> >> capacitor from the drain node to a regenerative point.
> >>
> >> I am working on a 2 switch flyback and some other schemes, but would
> >> like to try that novel idea out....
> >>
> >> Anyone knows a pointer to the thread?
> >
> >I'll have to go look at whatever clever idea I had. The circuit ended up
> >not working but not, I think, because of my inadequate snubbing.
> >
> >A circuit that I did not work on directly, but which I know worked well,
> >was a fairly high-power flyback that just had a diode-capacitor snubber,
> >but which then had a switcher from the snubber cap's voltage back to the
> >primary DC rail. I can't remember whether it was called an active
> >snubber or a regenerative snubber, but the circuit worked.
> >
> >(The company went down the tubes -- it was a startup trying to make a
> >super-efficient solar panel inverter that did not use electrolytics
> >anywhere, and would, thus, "last forever". It was run by someone with a
> >PhD in engineering, and I'm pretty sure it died due to lack of a sales
> >and marketing network.)
>
> "It was run by someone with a _PhD_ in engineering" _is_ probably why
> it failed >:-}
Probably the best electronic engineer I know has a Ph.D. in Engineering - on a design study for an electric motor for oil tankers using super-conducting windings.
His nick-name around the lab was "Puker" - which can be translated as somebody who makes other people throw up - because of his habit of coming up with simple, horrible solutions (many of them one-transistor) for other peoples circuit problems.
EMI took out some 25 patents naming him as the inventor, or one of the inventors, which do commemorate rather more complicated innovations.
Nobody would have wasted his time getting him to run a business - you can hire people for that.
--
Bill Sloman, Sydney