I’ll lead off with the statement that I’m a geek, and I don’t have any rational reason why I would need one of these beasties.

I’m in the market for an oscilloscope (why? good question… ask later). I’m browsing. As anyone I want the most bang for the buck. At the same time you want to know what the limit is. The high-end market is cornered by a couple companies: Tektronix and Agilent (used to be HP). I looked at the most expensive as a proxy for “best.”

So, what does half million buy ya? (Ok, the list price is $428,260, but you’ll invariably buy some options… hell a probe can cost nearly $30K.

What the hell am I smoking?

I am looking at (looking at like one looks at something like a McLaren F1 car) an Agilent DSAX96204Q scope.

What does it do that makes it cost as much as my house?

It is 63GHz scope.

Of course if it only took 63 billion samples per second it would be aliasing all to hell.

It takes 160GSa/s. 160 billion samples per second. The physics of this is completely mind-blowing.

Sure it’s a big number… 160 billion is a big number.

But we’re dealing with laws of nature here.

Light travels (in a vacuum) around 300,000,000 m/s or 186,000 miles/hour. In a billionth of a second it travels around 30cm — around a foot.

It follows that in 160 billionth of a second it travels 1.87 mm or 0.074 inch (a scoch over a 1/16″). This is in a vacuum. In copper signals travel 0.6C roughly.

In a wire a signal that is a 160 billionths of a second long is around 1mm long.

It’s traveling at very nearly the speed of light.

And there exists a device that can sample a signal every millimeter.

For only the cost of my house.

Holy crap.

Almost sounds cheap.

As a signal is traveling around 180,000 km/s (!!!) this takes a measurement every millimeter (!!!!!!!)

Think about that. Real hard. Wait for your brain to want to explode. Wait for your brain want to explore.

– = –

I think I’ll be getting a Rigol one of these days. Many, many, many orders of magnitude slower. (Maybe this one if I really splurge)