Re: OT: Covid's True Origins

Apr 20, 2025 Last reply: 1 year ago 23 Replies

I can usually take a few points on a breadboard or an eval board.

Many RF parts self-bias, or are more complex than a classic 3-terminal part.

Even worse, some have internal closed-loop bias things of undefined bandwidth. I hate that.

The RF boys always chop off their graphs to hide the bad bits. And a lot of parts are sold to work in some specific band, with tuned wire bonds or whatever, so wideband use is guesswork.

I used the HMC659 in the recent NIF modulator project. They are over $300 each. If you pull the output up with a current source and poke negative pulses into the input, it breaks down at about 16 volts. That was an interesting experiment.

Breaking things is fun. Well, cheap things.

Not so much guesswork as demanding of insight. If you haven't got any insight into how the thing works in its usual application, then you are reduced to guesswork.

Or read the data sheet with some insight into what might normally be going on.

Even marketing clown don't write data sheets that lead a lot of customers to blow up a lot of parts.

Asking the application engineer what might happen is less expensive, but means deferring to their expertise (when they have some).

<snipped the usual advertising>

Not for grown-ups.

I feel your pain. Life's a *bitch* at mm wave. Am I allowed to say that any more? Oh well, tough - I just did.

If you want to *fully* characterize such devices, it will cost a small fortune. But depending on the application, you may have to lay out the bread, because as you've already said, there's a paucity of information in the typical datasheet when it comes to 'extreme' operating conditions.

Or expensive things that a crowd of other people have paid for, yes.

Calling Harvard University a "Far Left Institution" would definitely have been considered a sign of dementia for about the past 400 years, but it's also symptomatic of the decision of the populist New Right in America to consider just about anyone with higher than a 6th grade education its mortal enemy.

Anyone other than its leadership, who as usual consist of a large proportion Ivy-babies themselves "do as I say, not as I do"

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