Yes 2016 will be a much longer year than usual. By one second. That is 31,536,001 seconds instead of 31,536,000. Be ready for a long night.
And in case you are interested in building your own atomic clock here is a nice one, done the old fashioned way. It is mainly analog computing. But you do need a little board for the final decoding. I’m going to use this one. I’m going to upgrade it with the LPC1115. It has more memory. And I have just the software development system that can use it.
Comments
8 responses to “It Is A Long Year”
OMG – an Extra Second! I want a Safe Space!
LOL – Happy New Year to you and Eric – and all those you care for.
Happy New Year!
Looking at the front end design for the receiver; using IF transformers designed for 455 kHz with 7500 pF capacitors to resonate at 60 kHz is going to result in a very low Q tuned circuit with a dynamic impedance around 300 ohms near resonance. It would work much better with a higher impedance in both stages. For example the FET probably has a transconductance of maybe 10,000 micro mhos. The FET is going to struggle to have any usable gain into such a low Z tuned circuit.
This could be done a lot better with a slightly modified design and still use off the shelf inductors. Probably 6 mH is a good starting value at 60 kHz.
Does anybody really know what time it is? Does anybody care?
I am more worried about building atomic bombs. netanyahu will start a war if he is indited for corruption as he is being interrogated now by israili prosecutors.
Randy,
The impedance of 680 uH at 60 KHz is about 250 ohms. Multiply by a Q of 10 and the impedance is about 2.5K – not unreasonable.
The coils for 455KHz IFs are tapped for a reason.
A Q of 10 at 60KHz is not unreasonable if all you want to do is keep out all the other crap in the atmosphere.
The real Q is in the quartz crystal.
What are you using for an antenna?
MMM,
A center tapped tuned small loop (24″ X 18″) at 60 KHz with a nice low noise JFET differential preamp. I’m planning on 21 turns of #26 or #24 wire.
It will have an inductance similar to the transformers so the Q is not going to be exceptional.