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Re: Cannot download IR2117_test.zip because of certificate error
Helmut wrote: "Have you seen Tony's answer?" Maybe not, because most of my messages don't seem to get relayed by email; they are only visible on Yahoo! groups site. I use several different computers with different email clients, and I often find I don't receive quite a few messages - not just mine - by email. Sometimes I receive an answer to a question, but not the original question. I have to go to the Yahoo! site to see all the messages in a thread. Perhaps it's because I access the Yahoo! groups with a non-Yahoo! email address? I don't know, but it used to work properly, years ago. Yahoo! is now just basically unreliable. If my business depended on Yahoo!, I would find a new provider. Regards, Tony |
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Re: Cannot download IR2117_test.zip because of certificate error
Hello Dave, Have you seen Tony's answer? He tried with the wrong web-address? One will get such temporay adresses with a right-mouse-click and "Copy link" on the filename in the Files section. The corerct address is below. IR2117_test.zip Best regards, Helmut |
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Re: Cannot download IR2117_test.zip because of certificate error
¿ªÔÆÌåÓýProbably not the only person. The error says your PC does not trust the certificates on xa.yimg.com. I have seen several reports of this here and on other groups. The info you have given is not enough to know if the error is with the server which has an invalid certificate, or with your PC which is missing a root certificate, or if you are in a commercial environment and there is a proxy that¡¯s messing things up ? E.g. ? https://superuser.com/questions/1083766/how-do-i-deal-with-neterr-cert-authority-invalid-in-chrome ? Hopefully clearing the browser cache and starting from the top of the files section will sort things out. If not make sure your browser is up to date. It looks like you are using CHROME and chrome needs to be up to date for its certificate checking to work reliably¡ Also note that xa.yming.com will actually be an array of load balanced servers so it could just be one has of the array has some issue. If so some times it will work and at other times it won¡¯t. ? .. hope this helps.. ? ? Dave G4UGM ? ? ? ? ? ?
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Re: Cannot download IR2117_test.zip because of certificate error
vermaak.jj@... wrote: "I am trying to download the IR2117_test.zip file found under "Files" Clicking on the link takes me to website?, but I get error message?NET::ERR_CERT_AUTHORITY_INVALID Am I the only one that cannot access the download files under TAB Files?" That sounds a bit like paranoia... The URI you posted is incomplete, and in its entirety, is a transient URI valid for only a short time, and likely valid for only one user - this is a peculiarity of Yahoo! platform, and frequently causes consternation in this group. The real URI for the file you seek is: Clicking on this link will probably just take you to Files > Lib. Use Ctrl-F to find the file on that page, which is quite long. I just checked it and the file you seek is there and downloadable. Regards, Tony |
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Re: Cannot download IR2117_test.zip because of certificate error
¿ªÔÆÌåÓýI get ¡°Requested resource is not available¡± ?from Apple Safari browser.Jim James Wagner Oregon Research Electronics
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Re: Single supply VCO
Hello
Would you, please, reveal the math performed by the MODULATE block on theIf I am wrong, I apologize, but not Helmut, nor anyone here, work at LTspice or are affiliated with them. Therefore, asking to "reveal" whatever LTspice thinks is not a request that anyone here can, or could divulge. -- Vlad ______________________ ltspicegoodies.ltwiki.org -- holding, among others: a universal analog/digital filter, block-level models for power electronics (and not only), math blocks with a more stream-lined approach, some digital ADC, DAC, (synchronous-)counter, JKflop, etc. |
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Re: LTSpice Model for Photo Triac - VOM160
Hi Andy, Sorry for the incomplete upload. Learning woes I guess. Actually the one modified from the original circuit ran. I think because I didn't delete any text that was on the original schematic. While the fresh? made one? wouldn't and has the error. So I got puzzled again what was going on. I actually did step 2 before but still it wouldn't run. I did not do step 3. So now I do both and wallah it runs! Please would like to request one more help. How do I now permanently save the part that has already MOC3083 on it instead of? LED_TRIAC_ZCS, and what needs to be done so I don't have to add the directive? ?.lib MOC308x.lib? everytime I use this part? Thanks and best regards, Eric
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Re: LTSpice Model for Photo Triac - VOM160
Eric wrote: ? ? "I uploaded both circuits so you can maybe is it okay you can take a look." So I copied over the two files (LED_TRIAC_ZCS.asy and?MOC308x.lib) that I said you needed. When I run "Heater-circuit-MOC3083_modified.asc", it won't run because that schematic tries to load "st_standard_snubberless_triacs_LTspice.lib" which isn't there either.? I don't think it's needed in that schematic, is it?? So then I copied that file over too, anyway.? Now when I run it, it runs without any errors.? Is this the one you said had an "Unknown subcircuit" error? When I run "Heater-circuit-MOC3083-fresh drawn.asc" (after having added the symbol and library files), I get the error about "Unknown subcircuit".? The reason is because you forgot to do steps (2) and (3) that I described earlier.? The text immediately under the symbol needs to be changed to "MOC3083", and there must be the line to include the library file that has its subcircuit definition: ? ? .lib MOC308x.lib Fix those two, then it should work. Regards, Andy |
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Re: LTSpice Model for Photo Triac - VOM160
Hi Eric, If you run LTspice with the schematic that's inside the ZIP file, then that is the problem.? When you open something in a ZIP archive, Windows creates a temporary copy of JUST that one file, nothing else.? So none of the library and symbol files are there with it.? They are still in the ZIP file, but not in the temporary folder where Windows put the schematic file before sending it to LTspice. You have to extract the contents of the ZIP file.? Then you can run it.? Running from a ZIP file works only if there are no other files involved. (I don't think it matters, but I use a separate program for opening ZIP files on my PC.? I'm aware that MS-Windows itself can open ZIP files, but I don't let it do that.) There is no need to move any files to other locations, not with this ZIP file. ? ? "By the way, the LTSpice XXVII program is on my C drive while I save all my trial schematics on my D drive. Is this an issue?" Nope. More later. Regards, Andy |
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Re: Single supply VCO
I completely agree with Helmut, that the MODULATE block works correctly.? It has whenever I have used it. None of us knows the actual code.? Well, Panama Mike does.? But he is not likely to reveal it. You can create your own FM modulator circuit (using a B source) with idt() to integrate the FM input voltage, and apply it to the phase of a sine wave, thus producing a correct frequency modulated signal.? The MODULATE block's output is the same.? Therefore I conclude that it PROBABLY also integrates the input voltage and adds it to the phase. Why are you asking? Andy |
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Re: LTSpice Model for Photo Triac - VOM160
Hi Andy, I have LTSpice XVII which was just updated then. When I opened the zip file, I just clicked into the heater circuit schematic file? and it opened automatically in the LTSpice space.?? So I clicked Run but I remember it displayed something like MOC308x.lib can't be found. I didn't know what was going on and I thought you will also see the same thing when you open it.? Thus I posted it . After reading your instructions, I loaded the .lib files to "sub" directory, and all symbols to the "sym" directory, and loaded the schematics to my drive D simulations file. Then on LTSpice space, I opened the saved schematics and Run it. Wallah it ran:). By the way, the LTSpice XXVII program is on my C drive while I save all my trial schematics on my D drive. Is this an issue? So now I tried to draw a simple fresh schematic using the newly loaded??LED_TRIAC_ZCS?part. It wouldn't run. It flagged this issue " Unknown subcircuit called in: xu2 n002 0 n003 0 led_triac_ZCS. So I tried to copy the original heater schematic, paste it into a new schematic page in LTSpice space, then modify it to be exactly like my fresh circuit, it works. So I'm not sure where the problem is.? I uploaded both circuits so you can maybe is it okay you can take a look. The description? is MOC3083 Trial Circuit Comparison. Thanks and best regards, Eric On Wed, Nov 21, 2018 at 11:08 AM Eric Henares <eohenares@...> wrote:
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Re: Trying to simulate a 27Mhz receiver. Couple of questions
Another thing comes to mind: It could be useful to do an .AC analysis rather than (or in addition to) .TRAN analysis.? .AC analysis involves sweeping the frequency, so it is helpful for looking at tuned circuits.? To do an .AC analysis, you should remove the Modulate component and substitute an ordinary voltage source (keeping the series resistor), with its "AC" value set to 1V.? In SPICE .AC analysis is a linear analysis, so you get the same results whether signals are microvolts or megavolts; therefore it is often convenient to set the signal source's amplitude to 1V. I might start with .AC analysis until I get the tuned circuits where I want them, then change to .TRAN analysis with the modulated signal source. An .AC analysis doesn't tell you anything about circuits that are nonlinear.? Therefore, it would be meaningless for the detector portion of your receiver.? Likewise, RF mixers in a heterodyne receiver would not simulate correctly in .AC analysis.? But it's useful for checking the linear RF circuits. Regards, Andy |
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Re: Trying to simulate a 27Mhz receiver. Couple of questions
Interposted -
*Plain Text* email -- it's an accessibility issue () no proprietary attachments; no html mail /\ <> On 2018-11-21 7:28 p.m., chuck@... [LTspice] wrote: Actually a BUNCH of questions. LOLUse a 27MHz voltage source with a Modulate device. (F2 or [Edit]->[Component]) -> SpecialFunctions -> modulate) Apply your modulation signal to the AM or FM input as required. Trying to simulate a "toy" receiverInsert a capacitor. Set its value to "{varCapVal}" (right-click on the cap symbol and type {varCapVal} into the Capacitance box) Set the capacitor value in a .param statement (e.g. ".param varCapVal=1u" (without the "" marks)) You can use a list for the varCapVal (Help is very useful for syntax help) to get a variety of capacitances, or enter a formula so that the capacitance varies with time (then use the oscilloscope to look for whatever characteristic is important, and use the time at the max/min of that characteristic to figure out what capacitance is desirable.) Can't use the PC out of the toy. Want to be able to turn VCC on and off to save battery life.I don't understand this question. The simulation has all the energy in the universe available; the PeeCee uses a little to simulate your circuit and calculate the answer. It takes very little time and/or battery. If you need the simulated Vcc to turn on/off, right-click on the V symbol you put on the schematic and set the off voltage, on voltage, delay time, on time, ... Brand new to spice and not the sharpest pencil in the drawer, so I really need some help. |
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Re: Trying to simulate a 27Mhz receiver. Couple of questions
Chuck asked about radio receiver simulations: ? ? "1.How do I add a antenna. Or can I use a 27Mhz voltage source." SPICE doesn't do antennas.? Yes, you can use a signal source, connected to the appropriate point in your circuit.? I'd recommend a voltage source in series with a resistance, because I'm sure the antenna doesn't behave like an ideal voltage source, and it would likely mess up your receiver circuit if driven directly by a voltage source. ? ? "Need to modulate it with 1K sig. How do I modulate the 27Mhz." There are a lot of ways to do that, depending on how you want it to be modulated.? AM?? FM?? PM? LTspice has a most helpful circuit element, called "Modulate".? It is an AM and FM modulator.? I strongly urge you to use that, rather than any other method for making an AM or FM signal for simulations.? Find it in the Components menu, in the [SpecialFunctions] folder.? You'll have to scroll to the end to find it.? The "Modulate2" component is the same except that it has quadrature (Sine and Cosine) outputs. To use them, connect the 1kHz voltage source to either the AM or FM input (not both).? The other input can either be connected to a suitable voltage, or left floating.? Then right-click on the Modulate symbol, and add these two parameters to the Value field: ? ? Mark=27MEGHz? Space=27MEGHz The Space parameter value will be the output frequency when the FM input voltage is 0V. The Mark parameter value will be the output frequency when the FM input voltage is 1V. Note that SPICE requires "MEG".? If you use "MHz" you'll get milliHertz.? Can be just "MEG" because SPICE ignores what comes after it. If you want the signal to be AM, you can set both Mark and Space to 27MEGHz and leave the FM input disconnected or grounded. If you want AM, the voltage that you apply to the AM input pin needs to be suitably offset, so that its value never goes negative.? When the voltage at the AM input just reaches 0V on the negative peaks, you are at 100% modulation, so anything more than that would be overmodulation.? Yes you could do that, but then you don't have a proper AM signal anymore. The output of the Modulate device has a 1 ohm output impedance.? So you probably should add a series resistor between it and your receiver circuit.? How much resistance, well that depends on what sort of antenna you have.? You might also want to attenuate the signal too -- either that, or drive the AM input with a very small voltage. ? ? "How can I tune a tank circuit? Variable cap? Model somewhere?" Do you want to change the tuning during a simulation?? It's probably better to run a simulation, then change the tuning and run another.? Use the .STEP command to automate this process. If you do want to vary a capacitor during a simulation, be careful because it's not just a matter of changing its capacitance.? That would violate conservation of charge.? LTspice lets you overcome that problem by specifying the charge instead of the capacitance.? See the Help page for capacitors. If you run into problems with your simulations, consider uploading the circuit you've done to the "Temp" folder, and send a message with your questions. Regards, Andy |
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Trying to simulate a 27Mhz receiver. Couple of questions
Actually a BUNCH of questions. LOL ? 1.How do I add a antenna. Or can I use a 27Mhz voltage source. Need to modulate it with 1K sig. How do I modulate the 27Mhz. Was able to model a sine wave source at 27Mhz but sticking the 1K signal on that is what is got me stumped.? Trying to simulate a "toy" receiver? How can I tune a tank circuit? Variable cap? Model somewhere? Can't use the PC out of the toy. Want to be able to turn VCC on and off to save battery life.? Brand new to spice and not the sharpest pencil in the drawer, so I really need some help.? Thanks Chuck |
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Re: Is there any good 8 Ohm 0.5W loudspeaker model?
¿ªÔÆÌåÓý
I am sorry if I sound ignorant or misled by my own lack of understanding the problem at hand but a little while ago In this forum I derived some equations for simulating an electrostatic loudspeaker using what is similar to the old type analogue computer approach
to simulate in LTspice the variation of capacitance with the voltage having assumed that the charge on the membrane remains constant. (also made reference to Weakepidia on the internet to try to get some understanding of how the ELECTROSTATIC loudspeaker works
basically) I am not an Audio engineer and I have not as yet fully explained the interesting curves I got. Unfortunatey, neither did the person who paused the question to the forum replied nor make any
comments on my brief work despite my publication in this forum of my hand written derivations. I still have my hand written notes and equations. The reason I have mentioned this work is that It occurs to me that by making inferences to the first law of thermodynamics
one can work out the power developed within the speaker having? taken the energy stored in the capacitors or electric field developed and more accurately consider the losses incurred in the process. If you are interested in my Ideas, please reply to this e-mail
and we will exchange views.? I think it would be interesting.
Best regards,
Michael P Kiwanuka
From: LTspice@... on behalf of rjc@... [LTspice]
Sent: 21 November 2018 18:25 To: LTspice@... Subject: [LTspice] Re: Is there any good 8 Ohm 0.5W loudspeaker model? ?
?
think of it this way - the loud speaker is like a
or a with relatively poor ratio that is near
input
google[] , []
SUM :: for adequate model you should include the physical membrane displacement tracking . . . which would make the model over exhaustive for processing power point of view -- that unless you succeed to define some simplified
mathematical model that relates the electrical I/O to mechanical response (the analogy is the
(about ) , etc. ...)
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Tony Casey
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