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Re: Incandescent lamp model

 

开云体育

LOL!? 4X the hits with the wrong spelling

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From: [email protected] <[email protected]> On Behalf Of Andy I via groups.io
Sent: Monday, March 17, 2025 12:31 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] Incandescent lamp model

?

Might try searching for "Wien Bridge".? And the incorrect spelling with "Wein".
Re: Incandescent lamp model

 

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I was trying for the “classical” hardware implementation (cf. HP201C, e.g.)

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I got a LTspice model working well, using a diode and filter feedback to adjust a behavioral resistor, but that’s cheating.

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From: [email protected] <[email protected]> On Behalf Of John Woodgate
Sent: Monday, March 17, 2025 12:22 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] Incandescent lamp model

?

That model is probably for a gas-filled lamp, but a pilot light is probably a vacuum lamp. That could make quite a difference. I'm surprised that a 6 V 10mA lamp is still made. Do you really need low distortion? Diode clipping can get down to about 1% with careful design. A JFET as a voltage-controlled resistor (VCR) can do better, but only for a one-off, because the FETs vary too much unless you use a very costly part designed and selected as a VCR.

On 2025-03-17 18:39, Bell, Dave via groups.io wrote:

I’m trying to adapt and use the model in LampModel.zip, uploaded by analogspiceman last September.

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The test circuit supplied works fine for a 120VAC lamp.

I want to adapt it to a small pilot lamp, as a stabilizer for a Wein network oscillator.

?

There are a number of parameters defined in the model, but except foe ambient temperature, not well explained.

I commented the .param block and passed them externally, and that works exactly the same, as expected.

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Now, can anyone suggest what needs “tuning”, to get? about 600 ohms at 10mA, after warm-up?

Ka, ambient temp (Kelvin) is easy.

Kc looks like design voltage (120RMS), but doesn’t really act like it; left alone.

Kf seems to be a heat transfer coefficient, maybe good for warmup timing, but slightly changes stable resistance.

CTf is a coupling factor from Tambient to Tfilament, sets warmup timing; left alone.

RTf is filament resistance, but changing that parameter makes only a very small difference to the preset, ~150 ohms.

?

Thanks,

Dave

--
OOO - Own Opinions only If something is true: * as far as we know - it's science *for certain - it's mathematics *unquestionably - it's religion

?

Virus-free.

Re: Incandescent lamp model

 

Might try searching for "Wien Bridge".? And the incorrect spelling with "Wein".
Re: Incandescent lamp model

 

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Where did I have DS1 ?

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From: [email protected] <[email protected]> On Behalf Of Richard Andrews via groups.io
Sent: Monday, March 17, 2025 12:24 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] Incandescent lamp model

?

Is "DS1" an actual part number? I see it as a HID xenon lamp.
Re: Incandescent lamp model

 

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I searched for “incandescent”…

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“lamp” returns 76 hits, such as clamp, differentialamp, CFL-lamp, Koren tubes, and my favorite:

“Electrical Pulsing of a Laser Diode for Usage in Fluorescence Microscopy.pdf??? ??Report File

Master of Science Thesis with LTspice simulation of step recovery diode and laser diode circuits”

?

?

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From: [email protected] <[email protected]> On Behalf Of Andy I via groups.io
Sent: Monday, March 17, 2025 12:09 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] Incandescent lamp model

?

Just FYI -

?

There must be several more incandescent models here in this group.? Others have simulated with them in Wien Bridge oscillators.? But Analogspiceman's models are quite good quality so it's a good place - but not the only one - to start.

?

Andy
Re: Incandescent lamp model

 

Is "DS1" an actual part number? I see it as a HID xenon lamp.
Re: Incandescent lamp model

 

开云体育

That model is probably for a gas-filled lamp, but a pilot light is probably a vacuum lamp. That could make quite a difference. I'm surprised that a 6 V 10mA lamp is still made. Do you really need low distortion? Diode clipping can get down to about 1% with careful design. A JFET as a voltage-controlled resistor (VCR) can do better, but only for a one-off, because the FETs vary too much unless you use a very costly part designed and selected as a VCR.

On 2025-03-17 18:39, Bell, Dave via groups.io wrote:

I’m trying to adapt and use the model in LampModel.zip, uploaded by analogspiceman last September.

?

The test circuit supplied works fine for a 120VAC lamp.

I want to adapt it to a small pilot lamp, as a stabilizer for a Wein network oscillator.

?

There are a number of parameters defined in the model, but except foe ambient temperature, not well explained.

I commented the .param block and passed them externally, and that works exactly the same, as expected.

?

Now, can anyone suggest what needs “tuning”, to get? about 600 ohms at 10mA, after warm-up?

Ka, ambient temp (Kelvin) is easy.

Kc looks like design voltage (120RMS), but doesn’t really act like it; left alone.

Kf seems to be a heat transfer coefficient, maybe good for warmup timing, but slightly changes stable resistance.

CTf is a coupling factor from Tambient to Tfilament, sets warmup timing; left alone.

RTf is filament resistance, but changing that parameter makes only a very small difference to the preset, ~150 ohms.

?

Thanks,

Dave

--
OOO - Own Opinions only If something is true: * as far as we know - it's science *for certain - it's mathematics *unquestionably - it's religion

Virus-free.
Re: Incandescent lamp model

 

Hello, I am looking at the files now. Be patient, because I am slow as molasses.
Re: Incandescent lamp model

 

Just FYI -
?
There must be several more incandescent models here in this group.? Others have simulated with them in Wien Bridge oscillators.? But Analogspiceman's models are quite good quality so it's a good place - but not the only one - to start.
?
Andy
Re: Incandescent lamp model

 

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Umm, yeah. Read 04 as 24!

?

From: [email protected] <[email protected]> On Behalf Of Andy I via groups.io
Sent: Monday, March 17, 2025 11:50 AM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] Incandescent lamp model

?

I think you mean 21 years ago, that he uploaded it.

?

He left us about 4-5 years ago.

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Andy
Re: Incandescent lamp model

 

Sorry, I am not near my PC so can't check it out just now.
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Andy
Re: Incandescent lamp model

 

I think you mean 21 years ago, that he uploaded it.
?
He left us about 4-5 years ago.
?
Andy
Incandescent lamp model

 

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I’m trying to adapt and use the model in LampModel.zip, uploaded by analogspiceman last September.

?

The test circuit supplied works fine for a 120VAC lamp.

I want to adapt it to a small pilot lamp, as a stabilizer for a Wein network oscillator.

?

There are a number of parameters defined in the model, but except foe ambient temperature, not well explained.

I commented the .param block and passed them externally, and that works exactly the same, as expected.

?

Now, can anyone suggest what needs “tuning”, to get? about 600 ohms at 10mA, after warm-up?

Ka, ambient temp (Kelvin) is easy.

Kc looks like design voltage (120RMS), but doesn’t really act like it; left alone.

Kf seems to be a heat transfer coefficient, maybe good for warmup timing, but slightly changes stable resistance.

CTf is a coupling factor from Tambient to Tfilament, sets warmup timing; left alone.

RTf is filament resistance, but changing that parameter makes only a very small difference to the preset, ~150 ohms.

?

Thanks,

Dave
Re: LM121 model??

 

SWEET! Thank you very much, eT. This looks to work in the circuit being modeled. Now I can probe a bit more to work out the intricacies.?
Re: LM121 model??

 

On Wed, Mar 12, 2025 at 11:59 AM, DerekK wrote:
I am trying to work out some old schematic and circuit issues and am looking for a model for the old LM121 opamp. Anyone have such a thing? I found the LM118, as I can use the LTSpice LT118A model. Now for the front end.
Hi
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I've made a LM121 model from the datasheet but didn't test everything.
I'll be uploading file "LM121_Model_20250317.zip" that include a test circuit, model file and symbol.
I'll also post a couple of snapshot of plots.
You are welcome to use if you wish.
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FYI-The LM108A used on the datasheet circuit is included with LTspice 24.
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eT
Re: How to create IEC 61000-4-5 surge waveform in time & s behavioral ?

 

On Mon, Mar 17, 2025 at 02:19 AM, <ericsson.sunshine@...> wrote:

Sorry, forgot, I have used 1e-9 today in Matlab, I didn't wait it ran all
200us, Just 23% to see the most shape of the leading, the scale is the same,
peak approx 40mV.
You only need the first 40us, and even 1us should already be enough...

-marcel
Re: defining special kind of behavioral for current controlled oscilator in ltspice

 

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It's common for the TUNE input to be voltage driven through a low value resistor. It may be that the YIG already has that resistor built-in, but it's usually external because the tuning current can be a few hundred mA, and the dissipation could be considerable.

--
Regards,
Tony

On 17/03/2025 16:08, Andy I via groups.io wrote:

If that is true, then john23's specifications are wrong, and the LTspice "model" I made for it is wrong.
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The Tune input should have been driven by a current, not by a voltage.
Re: defining special kind of behavioral for current controlled oscilator in ltspice

 

On Mon, Mar 17, 2025 at 03:56 AM, Tony Casey wrote:
That's exactly true. YIG are tuned by varying the magnetic field the element is in, hence the coils. This also defines the dynamic behaviour.
If that is true, then john23's specifications are wrong, and the LTspice "model" I made for it is wrong.
?
The Tune input should have been driven by a current, not by a voltage.
?
Andy
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Re: LF356 simulation errors

 

Thanks Tony and John,

LTspice v24.1.0 was installed automatically yesterday with the internal update. Today tried to update again and now installed new version 24.1.5

I've loaded the test simulation of LF356 and make sure to reset all settings, modified again the "Component attribute editor" to original setting for U2, applied the suggestions (rise/fall times and the option directive), now works perfectly... Thank you Tony!

Best regards, Stephano
Re: How to create IEC 61000-4-5 surge waveform in time & s behavioral ?

 

Sorry, forgot, I have used 1e-9 today in Matlab, I didn't wait it ran all 200us, Just 23% to see the most shape of the leading, the scale is the same, peak approx 40mV.
?
Best regards.
?
On Mon, Mar 17, 2025 at 09:14 PM, <ericsson.sunshine@...> wrote:

Hi, Marcel:
?
In fact, it doesn't matter to add a '-' sign in time or s-domain.
It just changes the positive/negative, instead of the amplitude.
?
Best regards.
?
On Mon, Mar 17, 2025 at 08:43 PM, <mhx@...> wrote:
I think I found it. When the time-domain waveform is plotted from t=0 to t=50us, it
shows a *negative-going* exponential pulse reaching -5.037kV at 960ns. (The shape is
approximately waht your picture shows, the scale is not.) At 41us it is about -20V. I am
sure that when Simulink is told to use a sample-rate of 10ns and an accuracy of 10e-9
or better, it will show the same thing. As should LTspice.

-marcel
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