On 2023-09-09 05:42, upsidedown@downunder.com wrote:> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI > <spamme@not.com> wrote: > >> >> Note the 1N4007 diodes are replaced by a regular bridge rectifier with >> suitable ratings. It is easier to model using 1N4007s than trying to find a >> bridge rectifier in LTspice. > > The 1N4007 works more like a PIN diode, the other 1N400x diodes are > normal diodes. >IIRC it's 1N4005 and up that are PIN structures. 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
Kill LED lamp flicker
Started by ●September 8, 2023
Reply by ●September 11, 20232023-09-11
Reply by ●September 11, 20232023-09-11
On 08/09/2023 8:10 pm, Mike Monett VE3BTI wrote:> piglet <erichpwagner@hotmail.com> wrote: > >> >> The model you used for 1N4007 has something very wrong - if I replace >> with one of the 600V types included with LTSpice then the crazy currents >> disappear and the circuit does more as you describe. Have you checked >> Pdiss in R4? >> >> piglet > > VII doesn't have the 1N4007, so I got the model from LTspice IV. It shows a > PIV of 1,500 v. There are no 600 V versions in IV. > > I see no crazy currents in IV or VII. Can you tell me more about what you are > seeing? > > I tried to plot the power in R4 but had no luck in IV or VII. I tried to > calculate pwr(V(x), V(a)) but got 9.65e+307 with no units. So I have to > guess. I'll try a 2W wirewound. > > >Problem solved! During line wrap demangling I had corrupted the 1N4007 model Ibv=10u to become bv=10u so the extraordinary diode currents in my sim were it breaking down at microvolts. Now it sims more like you saw. piglet
Reply by ●September 11, 20232023-09-11
On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 2023-09-09 05:42, upsidedown@downunder.com wrote: >> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI >> <spamme@not.com> wrote: >> >>> >>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with >>> suitable ratings. It is easier to model using 1N4007s than trying to find a >>> bridge rectifier in LTspice. >> >> The 1N4007 works more like a PIN diode, the other 1N400x diodes are >> normal diodes. >> >IIRC it's 1N4005 and up that are PIN structures. > >Cheers > >Phil HobbsThe higher voltage rectifiers often make great drift-step-recovery (Grehkov) diodes. 2KV negative pulse: https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1
Reply by ●September 11, 20232023-09-11
On 2023-09-11 14:08, John Larkin wrote:> On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 2023-09-09 05:42, upsidedown@downunder.com wrote: >>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI >>> <spamme@not.com> wrote: >>> >>>> >>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with >>>> suitable ratings. It is easier to model using 1N4007s than trying to find a >>>> bridge rectifier in LTspice. >>> >>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are >>> normal diodes. >>> >> IIRC it's 1N4005 and up that are PIN structures. >> >> Cheers >> >> Phil Hobbs > > The higher voltage rectifiers often make great drift-step-recovery > (Grehkov) diodes. > > 2KV negative pulse: > > https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1 >I'm impressed that it survived enough pulses for a full trace. ;) 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 ●September 11, 20232023-09-11
On Mon, 11 Sep 2023 14:14:38 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 2023-09-11 14:08, John Larkin wrote: >> On Mon, 11 Sep 2023 12:33:29 -0400, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 2023-09-09 05:42, upsidedown@downunder.com wrote: >>>> On Fri, 8 Sep 2023 08:10:41 -0000 (UTC), Mike Monett VE3BTI >>>> <spamme@not.com> wrote: >>>> >>>>> >>>>> Note the 1N4007 diodes are replaced by a regular bridge rectifier with >>>>> suitable ratings. It is easier to model using 1N4007s than trying to find a >>>>> bridge rectifier in LTspice. >>>> >>>> The 1N4007 works more like a PIN diode, the other 1N400x diodes are >>>> normal diodes. >>>> >>> IIRC it's 1N4005 and up that are PIN structures. >>> >>> Cheers >>> >>> Phil Hobbs >> >> The higher voltage rectifiers often make great drift-step-recovery >> (Grehkov) diodes. >> >> 2KV negative pulse: >> >> https://www.dropbox.com/s/q82toc257fv43z8/DSRD_neg-2KV.JPG?raw=1 >> > >I'm impressed that it survived enough pulses for a full trace. ;) > >Cheers > >Phil HobbsThe rep-rate was low, with about 50 amps forward and reverse current into the DSRD. Hers's a water-cooled Pockels Cell driver. https://www.dropbox.com/scl/fi/5arhyamrp0bl3tgb2fasn/DSC02771.JPG?rlkey=3ttcc2yt6s9nrtdouuv3aneol&raw=1 The big problem was inductors. I kept frying them when I was making 1200 volt pulses at 4 MHz. Skin effect and such. What worked was that air-core inductor, hand-wound on a selected Sharpie, with a gap-pad to conduct heat through the board to the water-cooled baseplate below.
Reply by ●September 12, 20232023-09-12
piglet <erichpwagner@hotmail.com> wrote:> > Problem solved! During line wrap demangling I had corrupted the 1N4007 > model Ibv=10u to become bv=10u so the extraordinary diode currents in my > sim were it breaking down at microvolts. Now it sims more like you saw. > > pigletI once tried to bypass the line wrap by zipping the files and uploading to Google Drive. But I got so many complaints that people could not unzip them that I gave up. Now, after having good experience with bare unzipped files, I may try again. As a favor, try this and see how it works: https://tinyurl.com/r6r2m9kc It will say "No Preview Available", but give you the opportunity to download the file. Do so, and separate the files into ASC and PLT. Now, any wrap will happen in your text editor. Set the line width to the maximum and you should have no trouble. I'm going to experiment with uploading ASC and PLT files directly. If I can get Google Drive to stop using one of its editors and wrapping the lines, then it should work. -- MRM
Reply by ●September 12, 20232023-09-12
Mike Monett VE3BTI <spamme@not.com> wrote:> I'm going to experiment with uploading ASC and PLT files directly. If I > can get Google Drive to stop using one of its editors and wrapping the > lines, then it should work.It works! I gave it gibberish extentions that it doesn't know what to do with. Just move the last letter in the extension to the first place. ASC = CAS PLT = TPL Here's the files: https://tinyurl.com/mr32zynw - cas https://tinyurl.com/upr8yeap - tpl No unzipping, no editing, no line wrap, just rename and go. -- MRM
