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Think I'll start a thread on a WWV calibrator

Better do it quick, they are defunding WWV and taking it off the air last I heard. Say it's not needed in today's computer age. N.I.S.T. Defunding Radio Stations WWV and WWVH in 2019

 

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Better do it quick, they are defunding WWV and taking it off the air last I heard. Say it's not needed in today's computer age. N.I.S.T. Defunding Radio Stations WWV and WWVH in 2019

That would be sad as it brings back old memories. WWV or the Russia RWM was how we would synchronize cryptographic stream systems at remote locations before GPS or high precision portable digital clocks.
The old tube gear had a PRNG with a daily key (card) to generate the sequence starting at 0000Z. On the remote receiver there was a clock time offset dial you could set to synchronize (at the WWV zero tone ) the locally generated decryption stream but it needed to be within a few seconds of the broadcast master station clock for the local cipher clock circuit to lock with the incoming data stream. If you were off stream there were buttons to time bump the stream up or down with changing audio chirps from the gear to tell if it was the correct offset for a time sync.

http://www.jproc.ca/crypto/kwr37.html

The tube flip-flips were used to make a Fibonacci shift register pseudo-random number generator.
Today this would be done with a single controller chip instead of 500 mini-tubes.
https://www.maximintegrated.com/en/app-notes/index.mvp/id/4400
https://github.com/kirbysayshi/tetris-prng

 

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Better do it quick, they are defunding WWV and taking it off the air last I heard. Say it's not needed in today's computer age. N.I.S.T. Defunding Radio Stations WWV and WWVH in 2019

Sad, Even computers set their clock by NIST. Not to mention all the "Atomic clocks" you can buy as a time standard.They will have to learn WiFi instead Unless the gov. shuts down the websight too.

Well (me putting my moderator hat on), this is very much off topic for this thread, It stops now. But we can carry on over here...

Is WWV going away?

 

Does anybody work with logic circuits, old or new?
Or non logic chip circuits?

If so, I'd like to know what frequencies you work with in those curcuits.

I dabble from time to time. In the 90s, I designed a few CPUs for the fun of it. These were all on wire wrapped boards. The fastest one had a 100MHz clock. I made a video showing it if you are interested.

I made a motorcycle simulator that was basically all digital. That's running around 50MHz.

A couple of years ago I picked up an Arty board to play with. I made an ECL interface for it and was clocking that at 1.4GHz. You can see a few scope shots here:
https://www.eevblog.com/forum/microcontrollers/typical-speed-of-fpgas/msg1282290/#msg1282290

Homemade CPUs here:

 

Lets talk about WWV as a calibration source

 

My 7D15 scope plug-in gives me the best of both worlds:

 

My 7D15 scope plug-in gives me the best of both worlds:
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While it is nice you also need a Tektronix 7000 series mainframe to plug it into.

Ron

 

While it is nice you also need a Tektronix 7000 series mainframe to plug it into.

I have half a dozen of them.

 

Those were and likely still are great scopes. When they came out they were Thee Scope. They were a part of several Navy test measurement and diagnostic equipment packages I put together, I want to say we were using the 7704 mainframes with the 4 plug in compartments.

Ron

 

When they came out they were Thee Scope.

When I worked at HP Labs in the late 70's, we wanted one of the 1GHz "real time" scopes Tek introduced. It was prohibited because we had to use HP equipment. The best HP had to offer at the time was a sampling scope. But we did have a lot of equipment to choose from.

 

When I worked at HP Labs in the late 70's, we wanted one of the 1GHz "real time" scopes Tek introduced. It was prohibited because we had to use HP equipment. The best HP had to offer at the time was a sampling scope. But we did have a lot of equipment to choose from.

Yeah, I can appreciate that. HP made some real nice scopes. During may early days like starting maybe early 70s the rules of thumb were simple. You want a scope?, Go buy a Tektronix scope. You want time and frequency domain? Go buy HP. Lastly if you want AC or DC lab standards then go buy Fluke. Life was really pretty simple.

I once had the opportunity to attend a HP seminar taught by Stephen Adam of HP. I believe he engineered what we fondly called the "Cookie Jar" and much of their wave guide tuning stuff. Really cool stuff. I was in Italy at the time so attending got me a round trip back home, I included some vacation time in there too.

Ron