[time-nuts] WWVB BPSK Receiver Project? (fwd)

[ehydra]

gary schrieb:
> Just meditating out loud, if you were to go push pull with a ferrite 
> antenna AND you are winding it yourself, you could avoid the biasing 
> resistors by putting a center tap in the antenna itself, then tie that 
> center tap to an appropriate bias voltage. I haven't seen this done, so 
> their may be a gotcha with that scheme, but the science is good. 

Works with SA602. A russian web-site shows differential turns on a 
ferrite rod. <tested>


> Generally you will get a lower noise circuit if the input device is an 
> amplifier rather than a buffer.

Yep.


> 
> Lanksford's input stage is essentially a push pull buffer, but I don't 
> see that cancelling 2nd harmonics like a push pull amp. But for a whip, 
> which is a single ended input, I don't see a way to get a differential 
> input. Not true for a ferrite antenna.

You can transformer couple the input. Then the whip is at DC and it is 
possible to let DC-current to ground. <tested>

- Henry


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