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Idunno about that; 5Ω at 1GHz is 0.8nH.  Even a small DFN with multiple parallel power pins, struggles to get that low from parallel bypass caps thru pads, pins and bondwires to the die.  At some point we have to assume good enough will do, or that the IC has solved some of these issues itself (onboard bypass?).

But that's also something like a 0.5ns step, let alone CW, so you're going pretty fucking fast there. :)

Also depends if it's class A; obviously it can't be in this example (Io(pk) > Icc) but for smaller signals it could, and then Vcc and Vee act in parallel, which helps.  In an extreme case, we might have a choke supplying an MMIC, or PP transistor amp, etc., and Icc is explicitly steady over a cycle; it's no accident LC-coupled RF amps are a popular choice (or perhaps the only option), heh.

Tim
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Repair / Re: Tektronix TDS754D - acquisition board test fail
« Last post by TERRA Operative on Today at 12:57:06 am »
These PSU's are known for bad caps occasionally, so you may be making a shopping list for new ones soon...
There's also the possibility you have a version of the PSU that absolutely needs at least one cap replaced regardless.

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I have some spare CRT boards for the TDS700 scopes if you need one.
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Projects, Designs, and Technical Stuff / Re: LCD Sourcing Troubles
« Last post by Someone on Today at 12:47:24 am »
If you really want the lowest prices you'll need to talk to the manufacturers direclty, but they are unlikely to even answer you if you're not buying a huge quantity (1k+).
While that might be true I'd still like to talk to them about MOQ and what prices might be like for larger orders.  Depending on their answer it might affect whether I want to purchase their LCD in smaller quantities, even if I have to buy the smaller quantity through regular websites.  I'd like to keep in mind what the issues might be when it comes time to order larger volumes of a part.
You won't even get to talk to manufacturers until you've already been ordering 1k+ qty through distributors, or are some billion dollar enterprise. LCDs are a competitive market with people booking out capacity well in advance.

What's the problem with dealing through a distributor? That's pretty much your only choice.
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Regarding: clients in very sensitive government facilities that don't allow anything that can transmit

You should also expect (at least, prepare an answer for) push-back even if you use NFC or any inductive coupling, because people will automatically switch off to the idea even if you can demonstrate it can only operate millimeters away. That's not the point as far as non-tech people are concerned. There's an extremely good chance that at least some will consider inductive coupling to be no different to radio comms, and not want such an implementation.
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RF, Microwave, Ham Radio / Re: QucsStudio status?
« Last post by szoftveres on Today at 12:25:37 am »
I've been using QucsStudio for a while and it would be too sad to see it go into waste. I think there is always a community out there who is willing to maintain this kind software (especially given that the license fee of its commercial alternative is $5k/year), however it's up to the owner/creator to release the source code.
A great example is GNU octave.
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General Technical Chat / Re: Baltimore Francis Scott Key Bridge collapse
« Last post by soldar on Today at 12:18:35 am »
I would like to see maritime law changed to make the insurers liable for these costs, though.  It's not okay that the federal government has to pick up the tab for incompetent maintenance, or contaminated fuel.
Where do you get the idea that the insurers are not liable?

The post above by @floobydust suggests they might be on the hook for a maximum of the ship's value + cost of cargo transport.  So probably north of $100mn, but well short of the cost of one replacement bridge.
Regardless of the liability, I would advise not legislating in the heat of the moment and pondering things very carefully. Legislating too quick makes for bad laws.

All countries, including the USA, have many ways of limiting liability because it is considered to result in a benefit to society in the big picture. Limited liability corporations, bankruptcy laws, etc. might seem unjust in specific cases but they benefit society as a whole.

Governments already pay for infrastructure out of taxes because it results in economic activity and development and well being.

If the government required every business to have unlimited insurance coverage then many businesses would have to shut down because it would not be affordable. 

I do not know but maybe if the USA required too much insurance or other requirements for ships and other forms of freight then that would result in much higher shipping costs or even in some ships or companies just refusing to go there.

It may well be that the USA considers the cost of rebuilding a bridge every few years more affordable than putting very onerous requirements on ships.

Legislating in the heat of the aftermath often makes bad law and has unwanted consequences.

Laws have to be considered and crafted very carefully and even then they often backfire.

The Jones Act requires vessels transporting freight within American ports to be American built and crewed. The ostensible purpose was to protect the American shipbuilding industry. In fact it totally backfired.

https://www.cato.org/publications/policy-analysis/jones-act-burden-america-can-no-longer-bear

I would advise to tread slowly and carefully and consider changes with great care.
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Is this really worth the trouble?

With respect, YES!

Steve
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General Technical Chat / Re: Admit your Brain lock
« Last post by TimFox on Today at 12:10:26 am »
On my Transistor issue:

Here it is cause it just happened again with an NPN. Does the transistor "START" to conduct with the .7v on its base or is it fully on with .7? I think my brain lock is the voltage range at which it amplifies and isn't just a switch?

Start with a NPN transistor with, say, +5V connected from the emitter to the collector through a current meter.
If you carefully and slowly increase the BE voltage from 0 to roughly 0.7 V, the collector current increases exponentially, reaching a “typical” current value for Vbe approximately 0.7 V.
The current increases rapidly, but not discontinuously.
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