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Beginners / Re: oscilloscope problem
« Last post by aliarifat794 on Today at 07:45:17 am »If possible, assign a static address to the oscilloscope.
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PCB/EDA/CAD / Looking for CADSTAR pcb Uplaod Program
« Last post by hello188 on Today at 07:41:02 am »Hi.
My company gave work to modify a PCB file which was done with the original version of CADSTAR Ver 1.3I.
I am trying to import these .cdo files to windows version.
However it seems I can only import data created by versions later than CADSTAR 7.
I searched this blog and elsewhere and found that there is a utility program called CADSTAR PCB Upload, which converts previous versions of CADSTAR files to Version 7.
Anyone has an idea on where I can get hold of it?
Thanks
My company gave work to modify a PCB file which was done with the original version of CADSTAR Ver 1.3I.
I am trying to import these .cdo files to windows version.
However it seems I can only import data created by versions later than CADSTAR 7.
I searched this blog and elsewhere and found that there is a utility program called CADSTAR PCB Upload, which converts previous versions of CADSTAR files to Version 7.
Anyone has an idea on where I can get hold of it?
Thanks
4
Repair / Re: HP54600B with spike problem with and without signal
« Last post by iMo on Today at 07:35:29 am »First tell us what are the voltages of your signals, it should be 5V aprox. Next pls indicate the name of the pins, like DQ4, /WR, /CS, /OE, A11 when talking the U33 for example.
The ramp on your last shot is suspicious. The U33 memory is 85ns access time (so the system clock in that part of system will not be higher than 10-12MHz), afaik, so you should see all signals well on your 100MHz scope.
When you see such a slow ramp you may try (as a test or a quick workaround) to wire a 1k pullup (against the 5V) on that signal, sometimes it may help.
The ramp on your last shot is suspicious. The U33 memory is 85ns access time (so the system clock in that part of system will not be higher than 10-12MHz), afaik, so you should see all signals well on your 100MHz scope.
When you see such a slow ramp you may try (as a test or a quick workaround) to wire a 1k pullup (against the 5V) on that signal, sometimes it may help.
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Test Equipment / Re: Siglent SDS800X HD 12 bit DSO's
« Last post by rf-loop on Today at 07:34:25 am »Your language and my language and then foreign language to both... english... dinglish ... and finglish .. and in user manual chinglish but still we mostly undertand... if we want.Imho, this is a feature.
My understanding of a feature in regards to a program, tool or software:
- Something that helps the user, like informations.
- Seome functionality that speeds up things.
- Some function you can do with a device.
Have not seen the use of the word "feature" for something that is bad on a device.
Resources might be limited, so this i would consider normal behaviour.
By finnish: Ominaisudet
Germany: Eigenschaften
In my english: Features (also Characteristics)
There are bad features and good features, nice and poor features... sometimes also awkward features and very sophisticated or advanced features.
I'm trying to understand, not playing "language police".
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Test Equipment / Re: SDS800X HD Review & Demonstration Thread
« Last post by eTobey on Today at 07:29:34 am »What do the values in the third column mean? I just dont get it. Even after the next day. I only see a proportinal relation to the record length.
SDS824X HD Trigger rate
I have deleted my off-topic posts in here, and i suggest others to do the same.
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General Technical Chat / Re: Do you think an LED is a resistor?
« Last post by Someone on Today at 07:26:59 am »That was your long winded and dithering proof:non linear system has linear approximation around a small operating point....
STOP THE PRESSES!
... oh wait, that's the underlying principle of how spice AC analysis works.
Small signal analysis has nothing to do with what we are discussing here.
The resistance I talk about is the static resistance, not the dynamic or incremental resistance of small signal analysis.
Try again.
So, we are now seeing the diode as a voltage dependent resistor. Let's see... what is the resistance 400mV? Let's zoom in:So to try and claim you're not relying on the well known small signal AC parameters is plainly incorrect.
[MASSIVE IMAGE]
I'd say it's about 23.2 kohm.
Let's see what is the resistance at, I don't know, 660 mV (about 5mA of diode current). We can compute it by hand of course, but on the graph we see it is 132 ohm.
[MASSIVE IMAGE]
Now, let's see if we can make something with these values...
[snipping conversational fluff]
Ok, exact same results, if we neglect a bit of rounding error in reading and setting the values.
Now, take your black boxes out of the fridge. Put the diodes D1 and D2, and the resistors R1 and R2 inside a black box each. Shuffle them around. And tell me: without looking inside the black boxes and without resorting to second order effects (like temperature dependence, or changing the other circuital parameters to change the operating points) can you tell me which are the diodes and which are the resistors, by simply measuring voltages, currents and powers?
If you dont like relying on small signal characteristics, perhaps "try again" with your explanation/justification.
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Test Equipment / Re: Amber model 3500 distortion / noise measuring set manual / service manual
« Last post by oddbits on Today at 07:26:33 am »yes 3500 , i have 2 , one in fair condition and one in good condition , both have dead battery , one does take power the other does not, so are they worth the hassle and time to try a repair ?, Thinking i may get one good one from the 2 ? , but like i say can not find any info on the web about them.
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General Technical Chat / Re: Do you think an LED is a resistor?
« Last post by Berni on Today at 07:21:26 am »Resistor < Linear resistor U Nonlinear resistor
Nonlinear resistor < incandescent lamps U diodes U ...
So, you can still call it a diode, recognize that it is a nonlinear resistor and, as such, that it belongs to the more general set of resistors.
Does this make any sense to you?
It does not make sense.
All resistors exhibit electrical resistance.
All of those semiconductor devices indeed also exhibit electrical resistance.
However not all devices that exhibit electrical resistance are resistors as they are not components purposely designed to implement a well defined resistance.
Does not matter what you understand as "resistor", the vast majority of forum members you are talking to on here understand it as a device specifically designed to implement a well defined amount of resistance. You don't have the authority to redefine established industry words used by others.
QuoteWhat you are trying to say is that a diode exhibits the effect of "electrical resistance" or "resistivity".The point I make is that this is ALL a diode does.
This effect is not particularly special and just describes that the device can consume electrical power and turn it into something else,
Huge resistance when reverse biased, small resistance when forward biased. This is not a side effect. It is what it does (if we neglect secondary effects due to parasitics in real devices).
It does not store energy in the electric field.
It does not store energy in the magnetic field.
It does not do whatever sorcery a memristor does.
It just oppose a resistance that takes power out of the circuit.
Yes we all agree on here that at some fixed DC operating point a diode acts like resistance.
The point is that a diode is nothing special at doing this. The laws of physics force all power consuming components to look like resistors in steady state DC. This means that at a fixed DC operating point even a memristor is actually just electrical resistance, much like a diode acts as purely electrical resistance at that DC state.
Like what else do you expect an component to do at DC? It can either act as a power source (like a voltage or current source) or it can resist the flow of current hence resistance. There is nothing else for a component to do at DC.
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General Technical Chat / Re: Do you think an LED is a resistor?
« Last post by SiliconWizard on Today at 07:18:36 am »That's, once again, just about modeling. You can model all your heart's content, if you find that fun or see any practical use. Ultimately, it's just MODELS.
You're taking an I-V characteristic, basically, and claim that R = U/I, except that R here is a function of U (or I). Which makes it a dubious use of the "resistor" term, as quite a few have already said.
It doesn't serve much purpose either, other than playing with I-V characteristics, which is something that is pretty basic electronics, and obviously useful in itself.
And yes, inductors and capacitors are a slightly different beast, as they involve derivatives and their model is thus a differential equation. But you can still express them in terms of a relationship between U and I; no pun intended.
If you further twist your definition of a resistor with differential terms, then inductors and capacitors also become "resistors" in your definition.
Obviously that's still playing with models, as real-world parts all have resistive, capactive and inductive components as parasitics, and while useful, even the Shockley approximation is ultimately just for the birds, as someone would say.
You're taking an I-V characteristic, basically, and claim that R = U/I, except that R here is a function of U (or I). Which makes it a dubious use of the "resistor" term, as quite a few have already said.
It doesn't serve much purpose either, other than playing with I-V characteristics, which is something that is pretty basic electronics, and obviously useful in itself.
And yes, inductors and capacitors are a slightly different beast, as they involve derivatives and their model is thus a differential equation. But you can still express them in terms of a relationship between U and I; no pun intended.
If you further twist your definition of a resistor with differential terms, then inductors and capacitors also become "resistors" in your definition.
Obviously that's still playing with models, as real-world parts all have resistive, capactive and inductive components as parasitics, and while useful, even the Shockley approximation is ultimately just for the birds, as someone would say.